THE EFFECTS OF OYSTER, CLAM AND MUSSEL SHELL SHAPE...
Transcript of THE EFFECTS OF OYSTER, CLAM AND MUSSEL SHELL SHAPE...
EFFECTS OF OYSTER SHELL SHAPE AND THICKNESS
ON ABSORPTION OF ELECTRON BEAM, GAMMA RAY, AND X-RAY IRRADIATION
By
ARTHUR GRANT HURST, JR.
A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE
UNIVERSITY OF FLORIDA
2005
Copyright 2005
by
Arthur Grant Hurst, Jr.
To my wife Ashley, my parents, and my family for their continued support and encouragement
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ACKNOWLEDGMENTS
I would like to extend thanks and gratitude to my committee chairman and major
advisor, Dr. Gary E. Rodrick. Without this guidance his work would not be possible.
Thanks are due also to my supervisory committee members, Dr. Ronald Schmidt and Dr.
Sally Williams, for all their help and guidance in the completion of this research. I would
like to express my appreciation to Carl Gillis and Florida Accelerator Services and
Technology of Gainesville, FL, for providing me the opportunity to perform research at
this facility. Thanks are also due to Food Technology Service, Inc. of Mulberry, FL, for
allowing me the opportunity to perform research at its facility. I would also like to thank
the National Center of Electron Beam Food Research at Texas A & M University of
College Station, TX, for aiding us in our research and for the efficiency and consideration
of the staff.
Bill Leeming and Southern Cross Sea Farms, Inc. of Cedar Key, FL, deserve
recognition for always providing top-quality clams. The efforts of fellow master’s
student Daniel Periu as well as all of my lab mates were invaluable in the completion of
this project.
In conclusion, I would like to thank my parents, Arthur and Darlene Hurst, for all
of their love and support. I would also like to thank my wife, Ashley, for all of her love
and support. Without her encouragement and support this research would not have been
possible
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TABLE OF CONTENTS page
ACKNOWLEDGMENTS ................................................................................................. iv
LIST OF TABLES............................................................................................................ vii
LIST OF FIGURES ......................................................................................................... viii
ABSTRACT...................................................................................................................... xii
CHAPTER
1 INTRODUCTION ........................................................................................................1
2 REVIEW OF LITERATURE.......................................................................................4
Vibrio vulnificus...........................................................................................................4 Radiation.......................................................................................................................6 Radiation Sources .........................................................................................................7 Radiation Dose..............................................................................................................8 Oysters ..........................................................................................................................9 Clams ..........................................................................................................................11 Mussels .......................................................................................................................12
3 MATERIALS AND METHODS ...............................................................................14
Source of Oysters........................................................................................................14 Source of Clams..........................................................................................................14 Sources of Mussels .....................................................................................................15 Dosimeter Source and Reading ..................................................................................15 Oyster, Clam and Mussel Measuring Protocol ...........................................................15 Electron Beam and X-ray Protocol.............................................................................16 Gamma Irradiation Protocol .......................................................................................17 Statistics......................................................................................................................18
4 RESULTS AND DISCUSSION.................................................................................19
Oyster Irradiation with Electron Beam.......................................................................19 Oyster Irradiation with X-Ray ....................................................................................26 Oyster Irradiation with Gamma ..................................................................................32 Clam Irradiation with Electron Beam.........................................................................39
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Clam Irradiation with X-ray .......................................................................................45 Clam Irradiation with Gamma ....................................................................................51 Mussel Irradiation with Electron Beam......................................................................58 Mussel Irradiation with X-ray ....................................................................................65 Mussel Irradiation with Gamma .................................................................................71
5 SUMMARY AND CONCLUSIONS.........................................................................80
APPENDIX
A OYSTER, CLAM, AND MUSSEL MEASUREMENTS ..........................................82
Oyster Measurements .................................................................................................82 Clam Measurements ...................................................................................................88 Mussel Measurement ..................................................................................................94 Oyster Irradiation Dose Measurements ....................................................................100 Clam Irradiated Dose Measurements........................................................................107 Mussel Irradiation Dose Measurements ...................................................................113
B OYSTER, CLAM AND MUSSEL PICTURES.......................................................119
LIST OF REFERENCES.................................................................................................122
BIOGRAPHICAL SKETCH ...........................................................................................126
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LIST OF TABLES
Table page A-1 Oyster Weight Measurements in g (5/1/05) .............................................................82
A-2 Oyster Dimension Measurements in cm (5/3/05) ....................................................84
A-3 Oyster Thickness Measurements in cm (5/4/05)......................................................86
A-4 Clam Weight Measurements in g (4/29/05) .............................................................88
A-5 Clam Dimension Measurement in cm (5/10/05) ......................................................90
A-6 Clam Thickness Measurement in cm (5/12/05) .......................................................92
A-7 Mussel Weight Measurement in g (5/12/05)............................................................94
A-8 Mussel Dimension Measurement in cm (5/20/05) ...................................................96
A-9 Mussel Thickness Measurement in cm (5/22/05) ....................................................98
A-10 Electron Beam irradiated oysters in kGy ...............................................................100
A-11 X-ray Irradiated Oysters in kGy.............................................................................102
A-12 Gamma Ray Irradiated Oysters in kGy ..................................................................104
A-13 Electron Beam Irradiated Clams in kGy ................................................................107
A-14 X-ray Irradiated Clams in kGy...............................................................................109
A-15 Gamma Ray Irradiated Clams in kGy ....................................................................111
A-16 Electron Beam irradiated mussels in kGy ..............................................................113
A-17 X-ray Irradiated Mussels in kGy............................................................................115
A-18 Gamma Ray Irradiated Mussels in kGy .................................................................117
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LIST OF FIGURES
Figure page 4-1 The internal absorbed dose oyster shells compared to the external absorbed dose
of the top shell of oysters after exposure to electron beam at 1 kGy. ......................19
4-2 The internal absorbed dose oyster shells as compared to the external absorbed dose of the top shell of oysters after exposure at 3 kGy..........................................21
4-3 Percent external top shell dose absorbed internally in oyster shells compared to mean thickness of top shell of oysters irradiated at doses of 1kGy and 3 kGy.......22
4-4 Percent external top shell dose absorbed internally in oyster shells as compared to curvature of top shell of the oysters irradiated at doses of 1kGy and 3 kGy. ......23
4-5 Percent external dose absorbed internally in oyster shells compared to weight of oyster shells irradiated with electron beam at doses of 1kGy and 3 kGy. ...............25
4-6 The internal absorbed dose oyster shells as compared to the external absorbed dose of the top shell of oysters after exposure to x-ray at 1 kGy. ...........................26
4-7 The internal absorbed dose of oyster shells as compared to the external absorbed dose of the top shell of oysters after exposure to x-ray at 3 kGy. ...........28
4-8 Percent external shell dose absorbed internally in oyster shells compared to thickness of oyster shells irradiated at doses of 1kGy and 3 kGy with x-ray. .........29
4-9 Percent external top shell dose absorbed internally in oyster shells compared to curvature of oyster shells irradiated at doses of 1kGy and 3 kGy with x-ray at. .....30
4-10 Percent external top shell dose absorbed internally in oyster shells compared to weight of top shell of oysters irradiated at doses of 1kGy and 3 kGy with x-ray....31
4-11 The internal absorbed dose oyster shells as compared to the external absorbed dose of the top shell of oysters after exposure to gamma at 1 kGy.........................33
4-12 The internal absorbed dose of oyster shells as compared to the external absorbed dose of the top shell of oysters after exposure to gamma at 3 kGy at. ....34
4-13 Percent external shell dose absorbed internally in oyster shells compared to thickness of oyster shell irradiated at doses of 1 kGy and 3 kGy with gamma. ......35
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4-14 Percent external top shell dose absorbed internally in oyster shells compared to curvature of oyster shells irradiated at doses of 1kGy and 3 kGy with gamma at...36
4-15 Percent external top shell dose absorbed internally in oyster shells compared to weight of oyster shells irradiated at doses of 1kGy and 3 kGy with gamma. ..........37
4-16 The internal absorbed dose clam shells as compared to the external absorbed dose of the top shell of clams after exposure to electron beam at 1 kGy at. ...........40
4-17 The internal absorbed dose clam shells as compared to the external absorbed dose of the top shell of clams after exposure at 3 kGy at........................................41
4-18 Percent external top shell dose absorbed internally in clam shells compared to thickness of clam shells irradiated with electron beam at 1kGy and 3 kGy. ...........42
4-19 Percent external top shell dose absorbed internally in clam shells compared to curvature of clam shells irradiated with electron beam at 1kGy and 3 kGy. ...........44
4-20 Percent external top shell dose absorbed internally in clam shells compared to weight of clam shells irradiated at doses of 1kGy and 3 kGy with electron beam. .45
4-21 The internal absorbed dose clam shells as compared to the external absorbed dose of the top shell of clams after exposure to x-ray at 1 kGy. .............................46
4-22 The internal absorbed dose of clam shells as compared to the external absorbed dose of the top shell of clams after exposure to x-ray at 3 kGy. .............................47
4-23 Percent external top shell dose absorbed internally in clam shells compared to thickness of clam shells irradiated at doses of 1kGy and 3 kGy with x-ray. ...........49
4-24 Percent external top shell dose absorbed internally in clam shells as compared to the curvature of clam shells irradiated at doses of 1kGy and 3 kGy with x-ray. .....50
4-25 Percent external top shell dose absorbed internally in clam shells compared to weight of clam shells irradiated at doses of 1kGy and 3 kGy with x-ray. ...............51
4-26 The internal absorbed dose clam shells as compared to the external absorbed dose of the top shell of clams after exposure to gamma at 1 kGy...........................52
4-27 The internal absorbed dose of clam shells as compared to the external absorbed dose of the top shell of clams after exposure to gamma at 3 kGy...........................53
4-28 Percent external top shell dose absorbed internally in clam shells compared to thickness of clam shells irradiated at doses of 1 kGy and 3 kGy with gamma. .......55
4-29 Percent external top shell dose absorbed internally in clam shells compared to curvature of clam shells irradiated at doses of 1kGy and 3 kGy with gamma at.....56
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4-30 Percent external top shell dose absorbed internally in clam shells compared to weight of clam shells irradiated at doses of 1kGy and 3 kGy with gamma. ............57
4-31 The internal absorbed dose mussel shells as compared to the external absorbed dose of the top shell of mussels after exposure to electron beam at 1 kGy.............58
4-32 The internal absorbed dose mussel shells as compared to the external absorbed dose of the top shell of mussels after exposure at 3 kGy. .......................................60
4-33 Percent external top shell dose absorbed internally in mussel shells compared to thickness of mussel shells irradiated with electron beam 1kGy and 3 kGy. ............61
4-34 Percent external top shell dose absorbed internally in mussel shells compared to curvature of mussel shells irradiated at doses of 1kGy and 3 kGy. .........................62
4-35 Percent external top shell dose absorbed internally in mussel shells compared to weight of mussel shells irradiated at 1kGy and 3 kGy with electron beam. ............64
4-36 The internal absorbed dose mussel shells as compared to the external absorbed dose of the top shell of mussels after exposure to x-ray at 1 kGy ..........................65
4-37 The internal absorbed dose of mussel shells as compared to the external absorbed dose of the top shell of mussels after exposure to x-ray at 3 kGy. ..........67
4-38 Percent external top shell dose absorbed internally in mussel shells compared to thickness of mussel shells irradiated at doses of 1kGy and 3 kGy with x-ray. ........68
4-39 Percent external top shell dose absorbed internally in mussel shells compared to curvature of mussel shells irradiated at doses of 1kGy and 3 kGy with x-ray.........69
4-40 Percent external top shell dose absorbed internally in mussel shells compared to weight of mussel shells irradiated at doses of 1kGy and 3 kGy with x-ray. ............70
4-41 The internal absorbed dose mussel shells as compared to the external absorbed dose of the top shell of mussels after exposure to gamma at 1 kGy . .....................72
4-42 The internal absorbed dose of mussel shells as compared to the external absorbed dose of the top shell of mussels after exposure to gamma at 3 kGy........73
4-43 Percent external top shell dose absorbed internally in mussel shells compared to thickness of mussel shells irradiated at 1 kGy and 3 kGy with gamma at. ..............74
4-44 Percent external top shell dose absorbed internally in mussel shells compared to curvature of mussel shells irradiated at doses of 1kGy and 3 kGy with gamma. ....75
4-45 Percent external top shell dose absorbed internally in mussel shells compared to weight of mussel shells irradiated at doses of 1kGy and 3 kGy with gamma..........77
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B-1 Picture of oysters with dosimeter envelopes placed on them (6/8/05)...................119
B-2 Picture of clams with dosimeter envelopes placed on them (6/8/05).....................120
B-3 Picture of mussels with dosimeter envelopes placed on them (6/8/05) .................121
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Abstract of Thesis Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science
EFFECTS OF OYSTER SHELL SHAPE AND THICKNESS ON ABSORPTION OF ELECTRON BEAM, GAMMA RAY, AND X-RAY IRRADIATION
By
Arthur Grant Hurst, Jr.
December 2005
Chair: Gary E. Rodrick Major Department: Food Science and Human Nutrition
The overall objective of this research was to determine the effects of shape and
thickness on the absorption of electron beam, gamma ray and x-ray irradiation levels in
raw oysters, clams and mussels. Groups of 100 oysters, 100 clams and 100 mussels were
shucked of their meats and measured for dimensions and thickness. Wild Apalachicola
oysters, farm raised Cedar Key clams and farm raised mussels from China were used for
this research. The oysters, clams and mussels were divided up into groups of 50, attached
with 3 film dosimeter strips each and irradiated at doses of 1 kilogray (KGy) and 3
kilograys (KGy). After irradiation the dosimeters were read using a spectrophotometer to
determine the internal and external doses.
Electron beam irradiation had the least uniform dose of the three sources. X-ray
irradiation had a more uniform dose than electron beam. Gamma ray irradiation had the
most uniform dose of the three doses. Oysters had a wider range of thicknesses and
dimensions than the clams and mussels. Clams had a smaller range of thicknesses and
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dimensions than the oysters, but the mussels had the smallest range of thicknesses and
dimensions. The electron beam and x-ray sources also showed signs of a concentration
of irradiation within the shell. In both of the sources the internal absorbed dose was
greater than the external or given dose.
There are statistical differences between the internal and external doses with all
three types of irradiation. Statistical analysis showed differences in the amount of
external doses absorbed internally between electron beam, x-ray and gamma ray.
Observations suggest that the thicknesses, curvatures and weights of the shells do not
independently have a significant effect on the amount of irradiation absorbed with in the
shell. The oysters also had the least uniform internal dose absorption. Internal clam
doses were more uniform than the internal oyster doses but not as uniform as the internal
mussel doses.
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CHAPTER 1 INTRODUCTION
Oysters, clams and mussels are of great importance to those who work with the
shellfish industry and those who consume them. For many, these bivalve shellfish are a
delicacy and for others a source of livelihood. However, these bivalve shellfish have
received much criticism in the past five years for their potential to cause disease and even
death. The illnesses and deaths are primarily due to the marine bacteria genera Vibrio
especially V. vulnificus and V. parahemolyticus (Tamplin et al., 1982). Both of these
organisms can be fatal, when consumed by at risk individuals. Vibrio vulnificus is
responsible for approximately 85 hospitalizations and approximately 35 deaths per year
in the United States (Centers for Disease Control and Prevention [CDC], 2003). Certain
individuals are at higher risk for this disease and likely to become infected from these
organisms. At risk individuals include individuals who suffer from a compromised
immune system, cirrhosis, diabetes, acquired immunodeficiency syndrome, cancer,
hemachromatosis or liver disease (Blake et al., 1979). This group of at risk individuals
makes up a large number of potential victims that has been estimated to be as large as 10-
15 million in the USA.
In light of the morbidity and mortality concerns of these Vibrio diseases transmitted
to at risk individuals by consuming raw oysters and clams, the shellfish industry is
regulated to reduce or eliminate the public health risk of Vibrio. Efforts to reduce the
associated morbidity and mortality from raw oyster consumption have led to increased
regulation of shellfish waters as well as increased efforts to inform the public through
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public bulletins and mandatory safety warnings in Florida, Louisiana and Texas. Despite
the efforts of increased regulation and information, the health concern still persists. This
has led regulatory authorities to issue new regionally specific food safety mandates that
pose significant historical changes in oyster commerce. The mandate (Food and Drug
Administration [FDA], 2003) calls for immediate compliance goals before the end of
2004 and additional, more stringent goals before the end of 2006. The goals include
implementation of new, innovative post-harvest treatments to reduce specific bacterial
loads on raw oyster products. The regulatory expectations call for technology that has
not been proven both in terms of food safety or market acceptance. Processing aids (e.g.,
depuration, relaying, freezing, pressure and irradiation) have been investigated with
respect to reducing levels of V. vulnificus and V. parahemolyticus (Blogoslowski and
Stewart, 1983; Motes and DePaola, 1996; Mestey and Rodrick, 2003; Berlin et al., 1996;
Dixon, 1992).
Irradiation of oysters is a processing technique which has promise for reducing the
safety concern of these organisms. While irradiation has not yet been approved for
seafood including oysters, irradiation of oysters has been investigated for decades. Vibrio
is destroyed by irradiation. Kilgen et al. (1988) assessed shellstock oysters and showed
that all Vibrio pathogens were significantly reduced to undetectable levels at a dose of 1
kGy. Although the Vibrio threat can be reduced or eliminated through irradiation many
obstacles must be overcome before it can be put into practice.
Perhaps the biggest obstacle to overcome is the obstruction and lack of uniformity
regarding absorption through the shell into the meat of the oyster. Dixon (1996) found
that dosimeters placed inside oyster shells received approximately half of the calculated
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dose that was calculated by the irradiation facility. The dose of radiation absorbed by the
meat is affected by the natural physical barrier of the shell. Shells may vary greatly in
size, thickness, and shape so absorption may vary even from oyster to oyster. In order for
irradiation to be a viable option in the shellfish industry the differences in oyster shells
size, thickness, and shape must be considered.
The overall objective of this research was to compare and contrast the percentage
of absorption of irradiation from a gamma ray source, electron beam and x-ray
irradiation. The specific objectives of this research were to (1) examine the differences in
absorbed dose of irradiation between the external top and internal sections of the shells of
oysters, clams and mussels; (2) compare and contrast the absorption of irradiation in
three different types of shellfish; (3) compare the thickness and curvature of the shells to
the internal dose.
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CHAPTER 2 REVIEW OF LITERATURE
Vibrio vulnificus
A public health risk exists for certain high risk individuals who consume raw or
undercooked oysters and clams. Crassostrea virginica, the American oyster and
Mercenaria campechiensis, hard-shelled clam have been implicated in several foodborne
outbreaks (Blake et al., 1980; Blake, 1983; DuPont, 1986). Many different bacterial and
viral agents such as Vibrio, Salmonella, Shigella, Hepatitis virus and Norwalk virus have
been isolated from shellfish (Blake et al., 1980). Although all of the organisms can cause
problems in oysters and clams Vibrio is the most serious organism in shellfish.
V. vulnificus is a Gram negative, halophilic rod-shaped bacterium that is found in
estuarine and marine environments (Blake, 1983; DuPont, 1986). The U.S. Gulf Coast is
the most common place to find V. vulnificus (Tamplin et al., 1982), yet V. vulnificus has
been isolated from the Atlantic Coast and Pacific Coast (Oliver et al., 1983; Kelly and
Stroh, 1988). Both salinity and water temperature play a important role in the detection
of V. vulnificus. Levels of V. vulnificus are much higher during the warmer summer
months and lower in waters with salinities higher than 35 ppt (Kelly, 1982). Vibrio
vulnificus is a ubiquitous marine and estuarine microorganism that can be found
throughout the world. This is considered naturally occurring organism whose presence in
the environment is not related to fecal pollution (Tamplin et al., 1982).
Infection by V. vulnificus arises from the ingestion of raw or inadequately cooked
oysters or clams or by exposure of wounds to contaminated water. A primary septicemia
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results from ingestion of V. vulnificus and is accompanied by gastroenteritis, chills, and
fever. Individuals who become infected through a wound show symptoms of rapid
swelling erythema around the wound, as well as, fever and chills (Blake et al., 1980).
Wound infections can also cause myositis, severe cellulites and are likely to lead to gas
gangrene (Klontz et al., 1988).
Infections by V. vulnificus are onset rapidly with a median incubation period of
approximately 12-16 hours (Blake et al., 1980). Vibrio vulnificus infections can be life
threatening. Approximately 50% of patients who develop primary septicemia die (Morris
and Black, 1985). In patients developing hypotension within 12 hours after hospital
admission the mortality rate can be as high as 90% (Klontz et al., 1988). After primary
septicemia sets in, many patients begin to develop secondary lesions on their extremities
that can result in necrotizing vasculitis in the muscles, which often result in amputations
(Howard et al., 1986). Several epidemiological studies have been conducted which
suggest that a relationship between several preexisting conditions and primary
septicemia. Cirrhosis, diabetes, hemochromatosis, kidney failure, liver and iron disorders
and any other immunocompromised conditions may cause individuals to be at risk (Blake
et al., 1979; Tacket et al., 1984). The effect of V. vulnificus on at risk individuals has led
regulatory authorities and industry to investigate ways to reduce or eliminate the impact
of this organism on the public.
Since 1980, the shellfish regulatory agencies and industry have put forth a strong
effort to reduce the health risk related to oysters and clams. Dry cold storage is the
current accepted practice for storage and handling of oysters. Oysters are harvested,
slightly cleaned, culled and either placed in croaker sacks or wax boxes and stored at
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refrigeration at 34-36°F in the dry cold storage method (Dixon, 1996). Bacterial
reduction and shelf life extension are not achieved by this method. This ineffective
method has led industry and regulatory authorities to look for innovative methods such as
irradiation.
Irradiation is an effective method in reducing V. vulnificus in oysters. When a large
enough dose of irradiation is applied the bacteria are reduced. Low doses of irradiation
are effective in significantly reducing V. vulnificus in shell stock oysters (Dixon, 1992).
The potential for irradiation to reduce V. vulnificus has led irradiation of shellfish to be
investigated.
Radiation
Radiation is the movement of energy from a source through matter or space.
Sound, light, microwaves, and a wide range of other forms of energy are all forms of
radiation. Ionizing and non-ionizing radiation are the main two irradiation categories of
Non-ionizing radiation, such as visible light and microwaves, lacks the energy to remove
electrons from the orbit of atoms. Ionizing radiation can interact with atoms and cause
electrons to become excited or move from a lower energy level to a higher energy level.
When significant ionizing radiation is present the electron can be ejected from the atom.
Electron separation from the atom causes ionization, creating a positive or negative ion
(Urbain, 1986). Once the electron is free from the atom, it can interact with other
materials and cause chemical structure changes in the material. In the case of food
irradiation, these chemical structure changes occur within the microorganisms present in
the food, cause the microorganisms damage and eventually death (Elias and Cohen,
1983). Death occurs in microorganisms either by the radiation interacting directly with
cell components or with adjacent molecules in the cell. Radiation damage to the cell can
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be caused directly by the ionizing ray or by free radicals,( ·H and ·OH,) created by the
breakdown of water. The radicals, (primarily ·OH) creates single strand and double
strand DNA breaks in the genetic material. Single and double strand breaks in DNA
occur due to chemical damage to the purine bases, pyrimadine bases and deoxyribose
sugar (Farkas, 2001). If the genetic material is not repaired then the cell cannot produce
crucial materials from the genetic material and will die (Grez et al., 1983).
Radiation Sources
Three types of ionizing radiation, gamma rays, x rays and electrons, are used in
food irradiation. The most prevalent form of ionizing radiation used in food irradiation is
the use of gamma rays. In food irradiation processing, two sources, Cobalt–60 and
Cesium–137, are used for producing gamma rays. Decay of the unstable radioactive
nucleus of Cobalt–60 and Cesium–137 cause gamma rays to be produced (Urbain, 1986).
Cobalt–60 produces two gamma rays with energy levels of 1.17 million electron volts
(MeV) and 1.33 MeV. Cesium–137 produces only one gamma ray with an energy level
of 0.66 MeV. Neither of these sources have the potential to produce radioactive food.
For significant radioactivity to be imparted into food energy levels larger than 15 MeV
must be used. The half-life of Cobalt–60 is 5.3 years. Cesium–137 however has a half-
life of 30.2 years. Gamma rays produced by Cobalt–60 and Cesium–137 have good
penetrating power, but can not be turned on and off. They are always producing
radiation. Containment and storage to prevent environmental contamination are a major
concern with these two sources. Both Cobalt–60 and Cesium–137 are generally
approved by the FDA in food products approved for irradiation (CFR, 1994).
Machine source electron beams and X-rays are also used in food irradiation
processing, yet these are not as widely used as gamma rays. The energy levels for both
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of these sources also are not large enough to convey radioactivity into the food. Electron
beams must have energy levels of less than 10 MeV and X-rays must have energy levels
less than 10 MeV to be allowed in the United States (21CFR179). Electron beams can be
efficiently created in high doses in a short amount of time and there is not a constant
radioactive source that must be contained. With electron beam machine sources the
radiation can be turned on and off, but electrons do not penetrate as well as gamma rays.
X-rays have greater penetrating power and can be turned on and off therefore
contamination is less of an issue. However, production of x-rays is not very efficient.
Radiation Dose
The nomenclature used to determine radiation dose have changed over time. In
older literature the rad was used as the unit for radiation dose delivered to a product or
radiation dose absorbed. One rad is equal to 100 ergs of absorbed energy per gram.
Current literature mostly uses the International System of Units (SI) unit of Gray (Gy).
One Gray is equal to 100 rads and 1 joule of energy absorbed per kilogram of food
(Urbain, 1986). The Food and Drug Administration (FDA) has approved several foods
at different doses mostly ranging from 1 kGy to 7 kGy. Fresh foods are approved for 1
kGy to delay maturation, all foods are approved at 1 kGy to prevent insect contamination,
Poultry is approved at 3 kGy to reduce pathogens, fresh red meat is approved at 4.5 kGy
and frozen red meat is approved at 7 kGy to reduce pathogens (Henkel, 1998) by the
FDA and the U.S. Department of Agriculture Food Safety Inspection Service (FSIS). All
of the doses are rather low. The only exception is spices which are approved up to 30
kGy (Henkel, 1998).
One major concern with oysters, clams, mussels and other bivalve shellfish is the
lack of uniformity in the dose. The desired target area for the radiation, the meat, is
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shielded by a shell that may vary greatly in thickness, conformation and shape. This shell
may reduce the dose being applied to the food. This lack of uniformity creates a situation
where researchers must either choose a maximum dose or a minimum dose as the focus
(Stein 1995). In this situation the researcher selects a minimum dose (Dmin) based on the
amount of radiation needed to achieve desired effects and a maximum dose (Dmax) where
no extra undesirable effects are created (Stein 1995). The extent of dose absorbed may
vary depending on a variety of factors. Dixon (1996) found that the dose calculated by
Food Technology Services of Mulberry, FL, a gamma ray food irradiation facility, was
twice the dose received by internal dosimeters. The calculated dose given to the product
may vary greatly from the dose that the meat of the product actually receives.
Research of irradiation of shellfish is focused around two possible advantages. The
first major advantage of irradiation is the deduction of pathogens such as Vibrio in the
shellfish such as oysters and clams. The second major advantage is the possibility of
increasing shelf life of shellfish such as mussels. The major disadvantage of irradiating
shellfish is the increased cost of the process. Overall the possibility of increasing the
safety of shellfish with only slightly increased cost is very promising.
Oysters
Irradiation is a relatively new form of food processing compared to drying or
heating. For nearly a century irradiation has been studied for processing food.
Strawberries were processed with irradiation in 1916 (Webb et al., 1987). Many types of
food have been irradiated since then. Fruits, vegetables, meats, fish, shellfish as well as
many other types of food have been irradiated.
Bivalve shellfish, such as oysters, clams and mussels are one type of food that is
currently being researched as a candidate for irradiation to reduce pathogens. Irradiation
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of oysters has been studied since the 1950s as a possible method of reducing V. vulnificus
and as a method to extend shelf life. Gardner and Watts (1957) used ionizing radiation to
treat oyster meats at low doses of 630 rads (0.63 kGy), 830 rads (0.83 kGy) and 3500
rads (3.5 kGy). They observed that undesirable “oxidized” and “grassy” odors developed
respectively in raw and cooked irradiated oyster meats. Gardner and Watts (1957)
concluded that irradiation would not be successful in oyster preservation due to the
continuation of enzyme action even with doses of 3500 rads (3.5 kGy) and 5°C storage.
In 1966, Novak and others irradiated canned oyster meats at 2 kGy. The irradiated
and control oysters were stored on ice for 23 days and tested at 0, 7, 14, 21, and 23 days.
A trained taste panel was used to determine that irradiated oyster meats were adequate for
up to 28 days and non irradiated oyster meats were acceptable only up to seven days
(Novak et al., 1966). Slavin et al. (1966) concluded that oyster meats optimally irradiated
at 2 kGy and stored at 0.6ºC resulted in shelf life of 21 to 28 days. Metlitskii et al.
(1968) showed that oysters irradiated at 5 kGy and stored at 2°C have a 60 day shelf life.
Liuzzo et al. (1970) studied the optimum dose that would extend shelf life and
result in the least alteration in food components of shucked oyster meats. They
determined that a dose of 2.5 kGy would extend the shelf life of oyster meat to seven
days on ice. Sensory quality of the irradiated meats was not significantly different from
the non irradiated meats until the seventh day. Liuzzo et al. (1970) also determined that
doses above 1 kGy altered the B-vitamin retention, percent moisture, percent ash,
glycogen content and soluble sugar content of oyster meats.
Kilgen et al. (1988) examined shellstock oysters and showed that all Vibrio
pathogens were significantly reduced to undetectable levels at a dose of 1 kGy. Doses of
11
1 kGy were not lethal to oysters. There were also no significant sensory changes at a
dose of 1 kGy. Mallet et al. (1991) irradiated shellstock oysters from Massachusetts and
determined that the survival times of oysters through six days was not affected by doses
of up to 2.5 kGy. Mallet et al. (1991) concluded that doses of 2.5 kGy or lower produced
a median shelf life of greater than 25 days. Also, Mallett et al. (1991) also used a trained
taste panel to determine that oysters irradiated at doses up to 3 kGy were acceptable.
Hepatitis A virus and rotavirus SA11 in oysters and clams were also studied by Mallett et
al. (1991). A dose of 2 kGy gave a D10 value for hepatitis A virus and a dose of 2.4 kGy
gave a D10 value for rotavirus Sa11.
In contrast to Kilgen et al. (1988), Dixon (1992) showed that 1 – 3 kGy doses of
gamma radiation stored at 4°C to 6°C were not effective in significantly extending the
shelf life of Florida shellstock oysters longer than the non irradiated controls. In addition,
Rodrick and Dixon (1994) found that the bacterial levels of V. vulnificus, fecals and
overall bacteria were reduced by about 2 logs with doses of 1 kGy and 3 kGy. But this
reduction only lasted a few days before the counts started to rise again to an even greater
number than the initial amount. Also, in contrast to previous work, the shelf life for these
oysters was not significantly extended as claimed by Mallet et al. (1991).
Clams
Clams have also been studied with respect to irradiation as a possible method to
reduce V. vulnificus or extend shelf life. Nickerson (1963), studied irradiation of clams
and determined that clam meats had a shelf life of 28 days with a dose of 4.5 kGy. Also,
at doses up to 8.0 kGy Nickerson (1963) showed that irradiated clam meats stored at 6°C
for 40 days showed no detectable differences from non-irradiated clam meats. Slavin et
al. (1963) also found that 4.5 kGy irradiated clams stored at 6°C were equal in quality to
12
non irradiated clam meats. A taste panel was used by Connors and Steinberg (1964) to
determine that clam meats irradiated at 2.5 kGy to 5.5 kGy were not significantly
different from non irradiated clam meats. Yamada and Amano (1965) determined the
optimum dose range to be 100-450 krads (0.1-0.45 kGy) to obtain a shelf life of four
weeks at 0°C-2°C in Venerupis semiddecus sata clams. Carver et al. (1967) determined
that shucked surf clam meats, Spisula solidissima, air packed in plastic pouches have an
optimum dose of 450 krads with a shelf life of 50 days at 0.6°C. Non treated clam meats
have a shelf life of 10 days at 0.6°C. Carver et al. (1967) also determined that clams
treated with doses of 100 – 200 krads have a shelf life of 40 days at 0.6°C. Harewood et
al (1994) evaluated the effects of gamma radiation on bacterial and viral loads as well as
shelf life in Mercenaria mercenaria hard shell clams. Radiation D10 values were 1.32
kGy for total coliforms, 1.39 kGy for fecal coliforms, 1.54 kGy for E. coli, 2.71 kGy for
C. perfringens and 13.5 kGy for F-coliphage.
Mussels
Irradiation of Mussels has been studied as well though to a lesser extent than have
clams and oysters. Irradiation of mussels is of concern due to the possibility of
increasing shelf life. Lohaharanu et al. (1972) examined shucked mussel meats and
determined that the optimum dose of irradiation was 150-250 krads (0.15-0.25 kGy). The
shelf life for the irradiated mussels were six weeks at 3˚C and the shelf life for the
nonirradiated mussels was three weeks at 3˚C. Since mussels are not very susceptible to
V. vulnificus and are generally eaten cooked irradiation of mussels has not been
researched to the degree that clams and oysters have. Extension of shelf life is one
possible benefit of irradiating oysters however.
13
Oysters, clams and mussels only make up a small part of the body of research of
food irradiation. However, irradiation of oysters, clams and mussels may prove to be
important in providing a safe way of producing products which are safer for the consumer
and have a longer shelf life.
14
CHAPTER 3 MATERIALS AND METHODS
This research included examination of oysters, clams, and mussels for differences
and similarities between shape, weight and size. The absorption of gamma ray and
electron beam irradiation in oysters, clams, and mussels were compared and contrasted.
Also this research included analyzing the shape, weight and size of the oysters, clams,
and mussels and their shells.
Source of Oysters
Florida shellstock oysters were used for analysis in this research. The source of the
oysters used in this analysis was Leavins Seafood, Inc. of Apalachicola, FL. Summer
oysters were harvested by Leavins Seafood, Inc. from approved shellfish harvesting
waters in the Apalachicola area. Leavins delivered the oysters to us at the Interstate 10
Agricultural Inspection Station in Live Oak, FL via refrigerated truck. The oysters were
transported on ice from Live Oak to the University of Florida in Gainesville, FL.
Source of Clams
Farm raised Florida hard shell clams were used in this research. The source of the
clams used in this research was harvested by Southern Cross Sea Farms, Inc. The clams
were harvested from approved shellfish harvesting waters in Cedar Key, FL. Southern
Cross Sea Farms breads, raises and harvests clams in Cedar Key, FL. The clams were
transported in coolers from Cedar Key to the University of Florida.
15
Sources of Mussels
Farm raised mussels from China were purchased from Northwest Seafood, Inc. in
Gainesville, FL and transported on ice to the University of Florida. The mussels were
imported, frozen and distributed by Beaver Street Fisheries in Jacksonville, FL.
Dosimeter Source and Reading
FWT 60-00 dosimeter strips produced by Far West Technology Inc. of Goleta, CA
were used to examine the dose of irradiation received in the inside and outside of the
oyster, clams, and mussel shells. The Florida Accelerator Services Technology (FAST)
facility’s dosimetery lab in Gainesville, FL was used to prepare and read all of the
dosimeter strips used in this research. These dosimeter strips were determined by Carl
Gilus the dosimetry expert for FAST to be the best fit for our dose, 1KGy to 3KGy, and
the spectrophotometer equipment available to us at FAST. All of the FWT 60-00
dosimeter strips were read using the FWT-100 Radiachromic Reader at FAST’s
dosimetery lab produced by Far West Technology Inc.
Oyster, Clam and Mussel Measuring Protocol
Oysters, clams and mussels (100 of each) were irradiated and assessed. Each of the
oysters, clams and mussels were all measured following this protocol. All of the
shellstock shellfish were weighed and measured at the University of Florida, Department
of Food Science and Human Nutrition. The meats were shucked from the shells with a
shucking knife, taking care to remove all of the meat. Both meat and shell were weighed,
to the nearest tenth of a gram, individually for each shellfish. After weighing the meat
was discarded. The top and bottom of the shell were also weighed individually and
together. The shells were measured for thickness, with calipers, at various locations over
the shell at a variety of places mapping the shell. Upper and lower shell parts were
16
compared to each other to determine the differences in weight between the upper and
lower parts of the shell. Overall shell weight was compared to meat weight. The thickest
and thinnest places were compared for each shell. Also, the thickness for each shell was
averaged. The heights, at the highest part of the shell, of both the upper and lower parts
of the shell were measured. In addition, the length of the upper and lower parts of each
shell (at the longest part) was measured. The length and height for each shell was
compared and contrasted. These comparisons were then used to determine the relative
curvature of each shell.
Electron Beam and X-ray Protocol
The electron beam source for this research was the National Center for Electron
Beam Food Research (NCEBFR) facility at Texas A and M University at College Station,
TX. The National Center for Electron Beam Food Research uses a 10 MeV Linear
Accelerator to irradiate food for research and commercial uses. The accelerator is a
linear Varian Accelerator in a Titan designed system.
The X-ray source for this research was also the National Center for Electron Beam
Food Research facility (NCEBFR) at Texas A and M University at College Station, TX.
The National Center for Electron Beam Food Research uses a 10 MeV mechanical
electron beam generator to produce electrons which are accelerated into a dense metal to
produce X-rays. A linear Varian Accelerator in a Titan designed system is focused on to
a Tantalum alloy converter sheet to produce the x-rays.
Doses of 1 KGy and 3 KGy, divided into the two same groups as set in the Food
Technology Service, Inc. Protocol, were also used at the NCEBFR electron beam and x-
ray facility. One hundred oysters, 100 clams and 100 mussels used in this part of the
research were shucked and cleaned prior to being sent to the NCEBFR facility. The
17
oyster, clam and mussel shells were prepared with dosimeter envelopes following the
same procedure used in the Food Technology Service, Inc. Protocol (see pictures in
Appendix B). The dosimetry lab was then used to fill all of the envelopes with dosimeter
strips. The shell was then closed with a drop of Elmer’s glue to prevent the shell from
opening during irradiation. All of the shells were then placed into Ziploc bags and placed
into a box with packing paper in-between the bags to protect the shells. The box of shells
was then shipped via FedEx to the NCEBFR facility. The shells were then run through
the electron beam till the desired dose was achieved as determined by the staff at
NCEBFR. After irradiation the shells were boxed up by the staff NCEBFR and shipped
via FedEx to the University of Florida. The shells were then taken to the FAST
doismetry lab and the dosimeter strips were read. The entire procedure was then repeated
for x-ray.
Gamma Irradiation Protocol
The gamma ray source for this research was Food Technology Service, Inc. facility
in Mulberry, FL. A Cobalt 60 (60Co) source was used at Food Technology to produce
gamma rays for large scale commercial irradiation. Food Technology was chosen over
smaller gamma units for its industrial scale because it could be used to irradiate all of the
oysters, clams and mussels at one time.
Two different doses, 1 KGy and 3 KGy were used in this research. These are the
doses that are currently being reviewed by the FDA for approval for use in seafood.
Oyster, clam and mussel shells (100 of each) were shucked and measured following the
Oyster, Clam and Mussel Measuring Protocol. Three dosimeter envelopes were attached
to each of the 300 shells using white carpenters glue from Elmer’s Products Inc. of
Columbus, OH. One envelope was attached to the outside of each of the upper shell.
18
Another envelope was attached to the outside of the lower shell. The last envelope was
placed in-between the two shells. Each of the envelopes was filled with one dosimeter
strip at the FAST dosimetery lab. The shell was then closed with a drop of white
carpenters glue to prevent the shell from opening during irradiation. The shells were then
equally divided into two boxes. The boxes of shells were transplanted to Food Tech and
one box was irradiated at 1 KGy and the other at 3 KGy. After the desired dose was
received the shells were taken back to Gainesville via car and read at the FAST
dosimetery lab.
Statistics
All of the statistics for this research were performed using Microsoft Excel XP.
Paired t-test were performed on the entire external and internal dose data. All t-tests were
performed with α = 0.05. Linear regression models were used in all of the figures to
determine trend. An α = 0.05 was also used for all of the linear regression models as
well. Multiple linear regression models were performed in Microsoft Excel XP with the
addition XLSTAT on all of the data for figures. All of the multiple linear regression
models used α = 0.05 as well.
19
CHAPTER 4 RESULTS AND DISCUSSION
Oyster Irradiation with Electron Beam
The initial experiments for this research were performed with electron beam
irradiation of shucked oysters. Oysters were harvested on May 6, 2005 from approved
shellfish harvesting waters in Apalachicola, FL and irradiated by electron beam at
NCEBFR on June 8, 2005. The oysters were shucked, measured and loaded with
dosimeter strips before irradiation. After irradiation the dosimeter strips that were placed
on the top oyster shell, bottom oyster shell and in between the oyster shells were read
using spectrophotometery.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-1. The internal absorbed dose shucked oyster shells as compared to the external
absorbed dose of the top shell of shucked oysters after exposure to electron beam at 1 kGy at NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.2774x + 1.307 R2 = 0.1814).
20
Figure 4-1 was created from the data in Table 10 (all Tables are located in
Appendix A). Data in Figure 4-1 show the internal absorbed dose compared to the
external top absorbed dose of the oyster shells irradiated at a dose of 1 kGy, as
determined by the staff of NCEBFR. The internal doses absorbed by the strips range
from 1.4 kGy to 3 kGy, have a median of 2.0 kGy and have a mean of 1.98 kGy.
External top absorbed doses range from 1.6 kGy to 4.1 kGy, have a median of 2.3 kGy
and have a mean of 2.46 kGy.
The mean dose absorbed was larger than the 1kGy dose given as determined by
NCEBFR for both external and internal dosimeters. In most cases the internal doses are
smaller than the doses received by the top of the oyster shells. However, in six of the
thirty eight oysters irradiated at 1 kGy the internal absorbed dose is higher than the
external top absorbed dose. External top dose mean is 0.47 kGy larger than the internal
absorbed dose mean. Linear regression of the data shows a positive relationship between
external dose and internal dose. This positive relationship is as expected. A higher
external dose should produce a higher internal dose. The line does not fit the data well
with an R2 value of 0.1814. The line only has an 18% fit with R2 values ranging from 0
to 1. External dose and internal dose are statistically significantly different (P<0.05).
Figure 4-2 was created from the data in Table 10. Data in Figure 4-2 show the
internal absorbed dose compared to the external top absorbed dose of the oyster shells
irradiated at a dose of 3 kGy, as determined by the staff of NCEBFR using p0hotometric
technique. The internal doses absorbed by the strips range from 1.4 kGy to 5.3 kGy, have
a median of 3.9 kGy and have a mean of 3.63 kGy. External top absorbed doses range
from 1.9 kGy to 6.7 kGy, have a median of 4.3 kGy and have a mean of 4.18 kGy.
21
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-2. The internal absorbed dose shucked oyster shells as compared to the external
absorbed dose of the top shell of shucked oysters after exposure at 3 kGy at NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.698x + 0.7163 R2 = 0.5105).
The mean dose absorbed was also larger than the 3 kGy dose given as determined
by NCEBFR for both external and internal dosimeters. In six of the sixty two oysters
irradiated at 3 kGy the internal absorbed dose is higher than the external top absorbed
dose. Having internal doses higher than the applied external doses is a concentration
phenomenon seen in both 1 kGy and 3 kGy oysters irradiated with electron beam. The
cause of this phenomenon is currently not known. External top dose mean is 0.51 kGy
larger than the internal absorbed dose mean. All of the oysters irradiated with electron
beam cover a larger range of doses than was to be expected. The external doses (applied
dose) cover a much larger range than we would expect. Not only does the internal dose
vary, but the external dose varies greatly as well. This issue is an undesirable effect of
electron beam. The doses in the oysters irradiated at 3 kGy are much more wide spread
than the doses of oysters irradiated at 1 kGy in Figure 4-1. Linear regression of the data
22
shows a positive relationship between internal dose and external dose. The regression
line for this data has a R2 value of 0.5105. External dose and internal dose are
statistically significantly different (P≥0.05).
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Top
Dos
e (%
)
Figure 4-3. Percent external top shell dose absorbed internally in the oyster shells as
compared to the mean thickness of the top shell of the oysters irradiated at doses of 1kGy and 3 kGy NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.1846x + 0.777 R2 = 0.0226).
Figure 4-3 was created from the data in Table 3 and Table 10. Data in Figure 4-3
show the percent external top shell dose absorbed internally in the oyster shells as
compared to the mean thickness of the top shell of the oysters. For mean thickness of the
top shell the range is 0.3 cm to 0.97 cm, the median is 0.46 cm and mean is 0.49 cm. The
percent external top shell dose absorbed internally range is 132% to 43%, the median is
90% and the mean is 86.8%.
Linear regression of this data shows a positive relationship between external dose
absorbed internally and mean shell thickness. It was expected that the percent external
top shell dose absorbed internally would decrease as the thickness increased, due to the
23
limited penetration of electron beam irradiation to penetrate thicker material as well as
thinner material. The data does not show this relationship. However, this line does fit
the data well with a R2 value of only 0.0226. Multiple linear regression of the data shows
no significant relationship between external dose absorbed internally and mean shell
thickness (P≥0.05). It was expected that thickness would have a significant effect on the
internal absorbed dose. This may be a result in the porous nature of the shell. If we were
to measure thickness and dose on a microscopic level the results may differ. Also the
effects of thickness on dose may be overshadowed by a more important unknown
variable.
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e
Figure 4-4. Percent external top shell dose absorbed internally in the oyster shells as
compared to the curvature of the top shell of the oysters irradiated at doses of 1kGy and 3 kGy NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.2084x + 0.8182 R2 = 0.0117).
Figure 4-4 was created from the data in Table 2 and Table 10. Data in Figure 4-4
show the percent external top shell dose absorbed internally in the oyster shells as
compared to the curvature of the top shell of the oysters. For curvature of the top shell
24
the range is 0.11 to 0.88, the median is 0.23 and mean is 0.24. The percent external top
shell dose absorbed internally range is 132% to 43%, the median is 90% and the mean is
86.8%.
The curvature of the oysters evaluated in this research did not vary as greatly as
first thought. The oysters appear to vary greatly in shape and size when examined by
hand. The curvatures of the assessed oysters are similar. Linear regression shows a
slight positive relationship between percentages of external dose absorbed internally and
top shell curvature. The line does not have a good fit however the R2 value is only
0.0117. Multiple linear regression models of the data show no statistically significant
relationship between curvature and percent of external dose absorbed internally (P≥0.05).
It was expected that curvature would have some sort of an effect on percentage of
external dose absorbed internally. The lack of a significant effect may also be a result of
a different variable overshadowing the effects of curvature. Or curvature may not have
an effect on percentage of external dose being absorbed internally when irradiated with
electron beam.
Figure 4-5 was created from the data in Table 1 and Table 10. Data in Figure 4-5
show the percent external top shell dose absorbed internally in the oyster shells as
compared to the weight of the top shell of the oysters. For weight of the top shell the
range is 19.8g to 41.5g, the median is 27.6g and mean is 27.9g. The percent external top
shell dose absorbed internally range is 132% to 43%, the median is 90% and the mean is
86.8%.
25
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 5 10 15 20 25 30 35 40 45
Top Shell Wt (g)
Inte
rnal
/Top
Dos
e
Figure 4-5. Percent external top shell dose absorbed internally in the oyster shells as
compared to the weight of the top shell of the oysters irradiated with electron beam at doses of 1kGy and 3 kGy NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = -0.0032x + 0.9561 R2 = 0.0059).
The oysters assessed in this research covered a range weights. This can be seen in
the top shell weights presented in this graph. Percentage of external dose absorbed
internally is rather evenly dispersed between the weights assessed. Linear regression
shows a slight negative relationship between percentages of external dose absorbed
internally and top shell weight. The line does not have a good fit which is evident by the
R2 value of 0.0059. Multiple linear regression models show no statistically significant
difference between top shell weight and percentage of external dose absorbed internally
(P≥0.05). There were no expectations for weight, but it was a factor that we hoped we
could use to produce a graphical model or an equation to predict the percentage of
external dose absorbed internally. However, for oysters irradiated with electron beam the
factors we investigated did not have enough statistical effect to produce a statically
significant model or equation.
26
Oyster Irradiation with X-Ray
The second set of experiments for this research was performed with x-ray
irradiation of shucked oysters. Oysters were harvested from approved harvesting waters
in Apalachicola, FL on May 6, 2005 and irradiated with x-ray at NCEBFR on June 26,
2005. The oysters were shucked, measured, irradiated with electron beam and loaded
with dosimeter strips that were placed on the top oyster shell, bottom oyster shell and in
between the oyster shells before irradiation with x-ray. After irradiation with x-ray the
dosimeter strips placed on the oysters were read with using spectrophotometery.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-6. The internal absorbed dose shucked oyster shells as compared to the external
absorbed dose of the top shell of shucked oysters after exposure to x-ray at 1 kGy at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = -0.1084x + 1.7874 R2 = 0.0141).
Figure 4-6 was created from the data in Table 11. Data in Figure 4-6 show the
internal absorbed dose compared to the external top absorbed dose of the oyster shells
irradiated by x-ray at a dose of 1 kGy, as determined by the staff of NCEBFR. The
internal doses absorbed by the strips range from 1.2 kGy to 2.6 kGy, have a median of
27
1.5 kGy and have a mean of 1.59 kGy. External top absorbed doses range from 1.3 kGy
to 3.0 kGy, have a median of 1.8 kGy and have a mean of 1.85 kGy.
The mean dose absorbed was larger than the 1kGy dose given as determined by
NCEBFR for both external and internal dosimeters. Yet, the means are closer and the
data is more consistent than the data presented for electron beam in Figure 4-1. Six of the
thirty eight oysters irradiated with x-ray at 1 kGy exhibit an internal absorbed dose are
higher than the external top absorbed dose. External top dose mean is 0.26 kGy larger
than the internal absorbed dose mean. Linear regression of the data shows a very slight
negative relationship between external dose and internal dose. However, the fit of the
line to the data is not good with R2 value for the regression is 0.0041. External dose and
internal dose are statistically significantly different (P≥0.05). It was expected that these
doses would be different due to x-ray’s lower energy and penetration.
Figure 4-7 was created from the data in Table 11. Data in Figure 4-7 show the
internal absorbed dose compared to the external top absorbed dose of the oyster shells
irradiated by x-ray at a dose of 3 kGy, as determined by the staff of NCEBFR. The
internal doses absorbed by the strips range from 1.2 kGy to 6.9 kGy, have a median of
3.8 kGy and have a mean of 3.82 kGy. External top absorbed doses range from 1.4 kGy
to 6.9 kGy, have a median of 4.2 kGy and have a mean of 4.12 kGy.
The mean dose absorbed was also larger than the 3 kGy dose given as determined
by NCEBFR for both external and internal doses. In eight of the sixty two oysters
irradiated at 3 kGy the internal absorbed dose is higher than the external top absorbed
dose. As with electron beam this concentration phenomenon is seen at doses of 1 kGy
and 3 kGy. External top dose mean is 0.31 kGy larger than the internal absorbed dose
28
mean. Linear regression of the data shows a positive relationship between internal dose
and external dose at a 95% confidence interval and a good data fit with a R2 value of
0.6808. The doses in the oysters irradiated at 3 kGy are much more wide spread than the
doses of oysters irradiated at 1 kGy. The oysters irradiated at 3 kGy with x-ray (Figure 4-
7) and 3 kGy with electron beam (Figure 4-2) are more similar to each other than the
oysters irradiated at 1kGy x-ray (Figure 4-6) and 1 kGy with electron beam (Figure 4-1).
External doses and internal doses of oysters irradiated with x-ray at 3 kGy are statistically
significantly different (P<0.05).
11.5
22.5
33.5
44.5
55.5
66.5
7
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-7. The internal absorbed dose of shucked oyster shells as compared to the
external absorbed dose of the top shell of shucked oysters after exposure to x-ray at 3 kGy at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.9596x - 0.1584 R2 = 0.6808).
Figure 4-8 was created from the data in Table 3 and Table 11. Data in Figure 4-8
show the percent external top shell x-ray dose absorbed internally in the oyster shells as
compared to the mean thickness of the top shell of the oysters. For mean thickness of the
top shell the range is 0.3 cm to 0.97 cm, the median is 0.46 cm and mean is 0.49 cm. The
29
percent external top shell dose absorbed internally range is 50% to 123%, the median is
90% and the mean is 91%.
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Dos
e (%
).
Figure 4-8. Percent external top shell dose absorbed internally in the oyster shells as
compared to the mean thickness of the top shell of the oysters irradiated at doses of 1kGy and 3 kGy with x-ray NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = -0.0916x + 0.9566 R2 = 0.0041).
The data for percentage of external top shell dose absorbed internally is more
tightly grouped for oysters irradiated with electron beam (Figure 4-3) than oysters
irradiated with x-ray (Figure 4-8). Linear regression of the data shows a slight negative
relationship between the percentage of external dose absorbed internally and mean top
shell thickness at a 95% confidence interval. The line for this data does not have a good
fit with a R2 value of 0.0041. Multiple linear regression models show no statistically
significant relationship (P≥0.05) between the external doses absorbed internally and
mean top shell thickness of oysters treated with x-ray. As with electron beam this was not
expected.
30
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e (%
).
Figure 4-9. Percent external top shell dose absorbed internally in the oyster shells as
compared to the curvature of the top shell of the oysters irradiated at doses of 1kGy and 3 kGy with x-ray at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = -0.3866x + 1.004 R2 = 0.0297).
Figure 4-9 was created from the data in Table 2 and Table 11. Data in Figure 4-9
show the percent external top shell x-ray dose absorbed internally in the oyster shells as
compared to the curvature of the top shell of the oysters. For curvature of the top shell
the data range is 0.11 to 0.88, the median is 0.23 and mean is 0.24. The percent external
top shell dose absorbed internally range is 50% to 123%, the median is 90% and the
mean is 91%.
The data from electron beam (Figure 4-4) and x-ray (Figure 4-9) is also very
similar for curvature. The data for electron beam appears to be slightly more tightly
grouped than the data for x-ray. A slight negative relationship is shown between
percentage of external dose absorbed internally and top shell curvature with linear
regression of at a confidence interval of 95%. However, with a R2 value of 0.0297 the
line does not fit the data well. Multiple linear regression models of this data show no
31
statistically significant relationship between percentage of external dose absorbed
internally and top shell curvature at a (P<0.05). It was expected that there would be some
effect of curvature on percentage of external dose absorbed internally. However,
curvature may be overshadowed by another factor or just not have an effect at all.
Figure 4-10 was created from the data in Table 1 and Table 11. Data in Figure 4-
10 show the percent external top shell dose absorbed internally in the oyster shells as
compared to the weight of the top shell of the oysters. For weight of the top shell the
range is 19.8g to 41.5g, the median is 27.6g and mean is 27.9g. The percent external top
shell dose absorbed internally range is 50% to 123%, the median is 90% and the mean is
91%.
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 5 10 15 20 25 30 35 40 45
Top Shell Wt (g)
Inte
rnal
/Top
Dos
e
Figure 4-10. Percent external top shell dose absorbed internally in the oyster shells as
compared to the weight of the top shell of the oysters irradiated at doses of 1kGy and 3 kGy with x-ray NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.0094x + 0.65 R2 = 0.0383).
Linear regression models of the data show a slight negative relationship between
percentages of external dose absorbed internally and top shell weight. The line does not
32
have a good fit however the R2 value is only 0.0059. No statically significant
relationship (P≥0.05) exists between external dose absorbed internally and top shell
weight in multiple linear regression models. None of the factors assessed for oysters
irradiated with x-ray have a statically significant effect on percentage of external dose
absorbed internally.
Oyster Irradiation with Gamma
The third set of experiments for this research was performed with 60Co gamma
irradiation of shucked oysters. Oysters were harvested on May 6, 2005 from approved
harvesting waters in Apalachicola, irradiated with gamma at Food Technology Inc. on
July 6, 2005. The oysters were shucked, measured, irradiated with electron beam,
irradiated with x-ray and loaded with dosimeter strips before irradiation with gamma.
After irradiation with gamma the dosimeter strips placed on the top oyster shell, bottom
oyster shell and in between the oyster shells were read using spectrophotometery.
Figure 4-11 was created from data in Table 12. Data in Figure 4-11 show the
internal absorbed dose compared to the external top absorbed dose of the oyster shells
irradiated by gamma at a dose of 1 kGy, as determined by the staff of Food Technology
Inc. The internal doses range from 1.2 kGy to 2.3 kGy, have a median of 1.8 kGy and
have a mean of 1.77 kGy. External top absorbed doses range from 1.3 kGy to 3.1 kGy,
have a median of 2.0 kGy and have a mean of 1.98 kGy.
The range of data for gamma is smaller than the range for electron beam or x-ray.
The mean dose absorbed was larger than the 1kGy dose given as determined by Food
Technology Inc. for both external and internal dosimeters. For gamma the means are
closer and the data is more consistent than the data presented for electron beam (Figure 4-
1) or the data presented for x-ray in (Figure 4-6). However, the external doses and
33
internal doses are statistically significantly different (P≥0.05). The internal absorbed
dose is not higher than the external top absorbed dose for any of the thirty eight oysters
irradiated with gamma at 1 kGy. External top dose mean is 0.26 kGy larger than the
internal absorbed dose mean. Linear regression of this data shows a positive relationship
between external doses and internal doses at a 95% confidence interval.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-11. The internal absorbed dose shucked oyster shells as compared to the
external absorbed dose of the top shell of shucked oysters after exposure to gamma at 1 kGy at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = 0.6965x + 0.3874 R2 = 0.8077).
Figure 4-12 was created from data in Table 12. Data in Figure 4-12 show the
internal absorbed dose compared to the external top absorbed dose of the oyster shells
irradiated by gamma at a dose of 3 kGy, as determined by the staff of Food Technology
Inc. The internal doses absorbed range from 1.8 kGy to 5.2 kGy, have a median of 3.9
kGy and have a mean of 3.95 kGy. External top absorbed doses range from 1.8 kGy to
5.5 kGy, have a median of 4.2 kGy and have a mean of 4.13 kGy.
34
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-12. The internal absorbed dose of shucked oyster shells as compared to the
external absorbed dose of the top shell of shucked oysters after exposure to gamma at 3 kGy at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = 0.9254x + 0.1138 R2 = 0.9372).
The data in Figure 4-12 follows the same layout as the electron beam (Figure 4-2)
and the x-ray (Figure 4-7), but is more uniform and consistent. However, the external
doses and internal doses are statistically significantly different with a confidence level of
95%. Zero of the oysters irradiated with gamma at 3 kGy exhibit a internal absorbed
dose higher than the external top absorbed dose. Gamma does not exhibit the
concentration phenomenon that affects electron beam and x-ray. External top dose mean
is 0.18 kGy larger than the internal absorbed dose mean. Linear regression of the data
shows a positive relationship between external dose and internal dose. With a R2 value of
0.9372 the regression line is almost a perfect fit. The data for gamma is more tightly
grouped than the data for electron beam and x-ray. Gamma produces more consistent
results than electron beam or x-ray in oysters.
35
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Dos
e (%
).
Figure 4-13. Percent external top shell dose absorbed internally in the oyster shells as
compared to the mean thickness of the top shell of the oysters irradiated at doses of 1 kGy and 3 kGy with gamma at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = -0.0608x + 0.9641 R2 = 0.0176).
Figure 4-13was created from data in Table 3 and Table 12. Data in Figure 4-13
show the percent external top shell gamma dose absorbed internally in the oyster shells as
compared to the mean thickness of the top shell of the oysters. For mean thickness of the
top shell the range is 0.3 cm to 0.97 cm, the median is 0.46 cm and mean is 0.49 cm. The
percent external top shell dose absorbed internally range is 74% to 100%, the median is
95% and the mean is 93%.
The shell thickness does not appear to affect the dose received in Figure 4-13. Data
in Figure 4-13. are more tightly grouped than the data for electron beam (Figure 4-3) and
the data for x-ray (Figure 4-8). A slight negative relationship exist between percentage of
external dose absorbed internally and mean top shell thickness when linear regression
models are ran with a 95% confidence interval. The line is not a good fit for the data
36
with a R2 value of only 0.0176. Multiple linear regression models show no statistically
significant relationship (P≥0.05) between mean top shell thickness and percentage of
external dose absorbed internally. It was expected that mean top shell thickness would
have a negative relationship to percentage of external dose absorbed internally. The lack
of a relationship may be caused by the use of macro measurements instead of micro
measurements or thickness may be overshadowed by other unknown factors. Oyster top
shell thickness does not have a statistically significant relationship (P≥0.05) to percentage
of external dose absorbed internally for any of the three irradiation sources tested.
00.20.40.60.8
11.21.41.61.8
2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e (%
).
Figure 4-14. Percent external top shell dose absorbed internally in the oyster shells as
compared to the curvature of the top shell of the oysters irradiated at doses of 1kGy and 3 kGy with gamma at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = -0.0055x + 0.9354 R2 = 6E-05).
Figure 4-14 was created from data in Table 2 and Table 12. Data in Figure 4-14
show the percent external top shell gamma dose absorbed internally in the oyster shells as
compared to the curvature of the top shell of the oysters. For curvature of the top shell
the range is 0.11 to 0.88, the median is 0.23 and mean is 0.24. The percent external top
37
shell dose absorbed internally for gamma irradiation range is 74% to 100%, the median is
95% and the mean is 93%.
The data for the gamma (Figure 4-14) is more tightly grouped than the data for
electron beam (Figure 4-4) or the data for x-ray (Figure 4-9). Linear regression at a 95%
confidence interval shows an extremely small negative relationship between the
percentage of external dose absorbed internally and top shell curvature. However, the fit
of the line is horrible with a R2 value of 0.00006. Multiple linear regression models of
the data show no statistically significant relationship (P≥0.05) between percentage of
external dose absorbed internally and top shell curvature. As with electron beam and x-
ray, curvature does not have a statistically significant (P≥0.05) effect on the percentage of
external dose absorbed internally in oysters irradiated with gamma.
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 5 10 15 20 25 30 35 40 45
Top Shell Wt (g)
Inte
rnal
/Top
Dos
e
Figure 4-15. Percent external top shell dose absorbed internally in the oyster shells as
compared to the weight of the top shell of the oysters irradiated at doses of 1kGy and 3 kGy with gamma Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = -0.0024x + 1.0004 R2 = 0.0241).
38
Figure 4-15 was created from data in Table 1 and Table 12. Data in Figure 4-15
show the percent external top shell dose absorbed internally in the oyster shells as
compared to the weight of the top shell of the oysters. For weight of the top shell the
range is 19.8g to 41.5g, the median is 27.6g and mean is 27.9g.
The percent external top shell dose absorbed internally range is 74% to 100%, the
median is 95% and the mean is 93%.
Percentage of external dose absorbed internally is rather evenly dispersed between
the weights assessed. Linear regression shows a slight negative relationship between
percentages of external dose absorbed internally and top shell weight at a 95%
confidence interval. The line does not have a good fit however the R2 value is only
0.0241. No significant relationship exists between external dose absorbed internally and
top shell weight in multiple linear regression models (P≥0.05). Top shell weight does not
have a statistically significant (P≥0.05) effect on percentage of external dose absorbed
internally in any of the three irradiation sources examined.
The external doses and internal doses are statistically significantly different
(P<0.05) in oysters irradiated with electron beam, x-ray and gamma at doses of 1 kGy
and 3 kGy. This is to be expected due to the barrier effect of the oyster shell against
irradiation. Top shell thickness, curvature and weight all have no significant effect on
percentage of external dose absorbed internally for oysters irradiated at 1 kGy and 3 kGy
with electron beam, x-ray and gamma. This was not expected, but as discussed above
this may be an effect of macro measurement instead of micro measurements or these
factors may be overshadowed by a more important unknown factor. Of the three sources
the data for gamma is most tightly grouped. Oysters irradiated with gamma also have
39
smaller ranges of data than electron beam and x-ray do. Gamma does not exhibit the
concentration phenomenon that is seen in electron beam and x-ray. Because of these
reasons gamma is the most promising irradiation source for irradiating oysters on a large
scale.
Further experiments need to be performed. Large scale experiments with pallets of
hundreds of bushels of oysters would provide the data needed to examine how effective
gamma is in industrial production. Further experiment with electron beam and x-ray are
also needed. Electron beam and x-ray may be more promising for half shell oysters.
Further research may add to the knowledge and direct how electron beam, x-ray and
gamma can be used to efficiently irradiate oysters.
Clam Irradiation with Electron Beam
Electron beam was used to irradiate clams at NCEBFR as well. Clams were
harvested on May 11, 2005 from Cedar Key and irradiated with electron beam on June 8,
2005. The clams were shucked, measured and loaded with dosimeter strips during the
before irradiation. After irradiation the dosimeter strips placed on the top clam shell,
bottom clam shell and in between the clam shells were read using spectrophotometery.
Figure 4-16 was created using the data in Table 13. Data in Figure 4-16 show the
internal absorbed dose compared to the external top absorbed dose of the clam shells
irradiated at a dose of 1 kGy, as determined by the staff of NCEBFR. The internal doses
absorbed by the strips range from 1.2 kGy to 2 kGy, have a median of 1.7 kGy and have a
mean of 1.70 kGy. External top absorbed doses range from 1.5 kGy to 3.1 kGy, have a
median of 2.1 kGy and have a mean of 2.12 kGy.
40
11.5
22.5
33.5
44.5
55.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-16. The internal absorbed dose shucked clam shells as compared to the external
absorbed dose of the top shell of shucked clams after exposure to electron beam at 1 kGy at NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.0405x + 1.6096 R2 = 0.0061).
The mean dose absorbed was larger than the 1kGy dose given as determined by
NCEBFR for both external and internal dosimeters. In most cases the internal doses are
smaller than the doses received by the top of the clam shells. However, in three of the
forty five clams irradiated at 1 kGy the internal absorbed dose is higher than the external
top absorbed dose. The external doses and internal doses are statistically significantly
different (P≥0.05). External top dose mean is 0.42 kGy larger than the internal absorbed
dose mean. Linear regression of the data at a 95% confidence interval shows a very
small positive relationship exist between external doses and internal doses. However the
fit of line to the data is not good with a R2 of 0.0061. The data for clams irradiated with
electron beam at 1 kGy are more tightly grouped than the data for oysters irradiated with
electron beam at 1 kGy.
41
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-17. The internal absorbed dose shucked clam shells as compared to the external
absorbed dose of the top shell of shucked clams after exposure at 3 kGy at NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.9134x + 0.152 R2 = 0.8344).
Figure 4-17 was created using the data in Table 13. Data in Figure 4-17 show the
internal absorbed dose compared to the external top absorbed dose of the clam shells
irradiated at a dose of 3 kGy, as determined by the staff of NCEBFR. The internal doses
absorbed by the strips range from 1.5 kGy to 4.2 kGy, have a median of 3.7 kGy and
have a mean of 3.50 kGy. External top absorbed doses range from 1.8 kGy to 4.6 kGy,
have a median of 3.8 kGy and have a mean of 3.78 kGy.
The mean dose absorbed was also larger than the 3 kGy dose given as determined
by NCEBFR for both external and internal doses. In nine of the fifty five clams
irradiated at 3 kGy the internal absorbed dose is higher than the external top absorbed
dose. The concentration phenomenon is seen in clams irradiated with electron beam as
well as oysters. However, the external doses and internal doses are statistically
significantly different (P<0.05). External top dose mean is 0.29 kGy larger than the
42
internal absorbed dose mean. Linear regression of the data shows a positive relationship
between external doses and internal doses with a 95% confidence interval. The line is a
good fit with a R2 value of 0.3158. The tighter grouping of data for clams irradiated with
electron beam than data for oysters irradiated with electron beam may be a result of the
more uniform shape and structure of the clams.
Figure 4-18 was created using the data in Table 6 and Table 13. Data in Figure 4-
18 show the percent external top shell dose absorbed internally in the clam shells as
compared to the mean thickness of the top shell of the clams. For mean thickness of the
top shell the range is 0.26 cm to 0.33 cm, the median is 0.29 cm and mean is 0.29 cm.
The percent external top shell dose absorbed internally range is 50% to 125%, the median
is 92% and the mean is 88%.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5
Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-18. Percent external top shell dose absorbed internally in the clam shells as
compared to the mean thickness of the top shell of the clams irradiated with electron beam at doses of 1kGy and 3 kGy NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.217x + 0.8137 R2 = 0.0005).
43
Linear regression of the data shows a small positive relationship between the
percentage of external dose absorbed internally and the mean top shell thickness at a 95%
confidence interval. However, the line is not a good fit with a R2 value of only 0.0005.
The percent of external top shell dose absorbed internally covers a range of 75%. The
percentages of doses received internally from the electron beam are not very uniform.
Multiple linear regression models shows no significant relationship between the percent
of external top shell dose absorbed internally and the mean top shell thickness (P<0.05).
As with oysters, thickness does not have a statistically significant effect (P≥0.05) on the
percentage of external dose absorbed internally in clams irradiated with electron beam.
Figure 4-19 was created using the data in Table 5 and Table 13. Data in Figure 4-
19 show the percent external top shell dose absorbed internally in the clam shells as
compared to the curvature of the top shell of the clams. For curvature of the top shell the
range is 0.26 to 0.39, the median is 0.33 and mean is 0.33. The percent external top shell
dose absorbed internally range is 50% to 125%, the median is 92% and the mean is 88%.
The curvatures of the clams analyzed in this research are very uniform. A negative
relationship exists, at confidence interval of 95%, between the percentage of external
dose absorbed internally and the top shell curvature when linear regression is applied to
the data. However, with an R2 value of 0.0237 the line is not a good fit. In addition,
multiple linear regression models of the data show no statistically significant relationship
(P≥0.05) between the percentage of external dose absorbed internally and the top shell
curvature. Like oysters top shell curvature was expected to a significant effect on the
percentage of external dose absorbed internally. The unexpected result may be an effect
44
of measuring techniques or a result of other factors overshadowing the effect of curvature
on the percentage of external dose absorbed internally.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e(%
)
Figure 4-19. Percent external top shell dose absorbed internally in the clam shells as
compared to the curvature of the top shell of the clams irradiated with electron beam at doses of 1kGy and 3 kGy NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = -1.1461x + 1.2569 R2 = 0.0237).
Figure 4-20 was created using the data in Table 7 and Table 13. Data in Figure 4-
20 show the percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clams. For weight of the top shell the
range is 10.0g to 20.6g, the median is 13.0g and mean is 13.9g.
The percent external top shell dose absorbed internally range is 50% to 125%, the
median is 92% and the mean is 88%.
Linear regression shows a positive relationship between percentages of external
dose absorbed internally and top shell weight at a 95% confidence interval. The line does
not have a good fit however the R2 value is only 0.0005. No statistically significant
relationship (P≥0.05) exists between external dose absorbed internally and top shell
45
weight in multiple linear regression models with a 95% confidence level. Like thickness
and curvature, weight is not a statistically significant factor in determining the percentage
of external dose absorbed internally in clams irradiated with electron beam. Other factors
or thickness, curvature and weight must be examined in order to determine the factors
that effect percentage of external dose absorbed internally.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Top Shell Weight (g)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-20. Percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clam irradiated at doses of 1kGy and 3 kGy with electron beam NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.217x + 0.8137 R2 = 0.0005).
Clam Irradiation with X-ray
Shucked clams were also irradiated with x-ray for this research. Clams were
harvested on May 11, 2005 from Cedar Key, irradiated with x-ray at NCEBFR on June
26, 2005. The clams were shucked, measured, irradiated with electron beam and loaded
with dosimeter strips before irradiation with x-ray. After irradiation with x-ray the
dosimeter strips placed on the top clam shell, bottom clam shell and in between the clam
shells were read using spectrophotometery.
46
11.5
22.5
33.5
44.5
55.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-21. The internal absorbed dose shucked clam shells as compared to the external
absorbed dose of the top shell of shucked clams after exposure to x-ray at 1 kGy at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.3976x + 1.0481 R2 = 0.3738).
Figure 4-21 was created from the data in Table 14. Data in Figure 4-21 show the
internal absorbed dose compared to the external top absorbed dose of the clam shells
irradiated by x-ray at a dose of 1 kGy, as determined by the staff of NCEBFR. The doses
absorbed internally range from 1.2 kGy to 3.0 kGy, have a median of 1.9 kGy and have a
mean of 1.9 kGy. External top absorbed doses range from 1.2 kGy to 4.2 kGy, have a
median of 2.2 kGy and have a mean of 2.23 kGy.
The mean dose absorbed was larger than the 1kGy dose given as determined by
NCEBFR for both external and internal dosimeters. External doses and internal doses of
clams irradiated at 1 kGy with x-ray are statistically significantly different (P<0.05). In
eight of the forty five clams irradiated with x-ray at 1 kGy the internal absorbed dose are
higher than the external top absorbed dose. External top dose mean is 0.33 kGy larger
47
than the internal absorbed dose mean. External dose and internal dose have a positive
relationship in linear regression models with a R2 value equal to 0.3738.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-22. The internal absorbed dose of shucked clam shells as compared to the
external absorbed dose of the top shell of shucked clams after exposure to x-ray at 3 kGy at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.6603x + 1.2588 R2 = 0.5929).
Figure 4-22 was created from the data in Table 14. Data in Figure 4-22 show the
internal absorbed dose compared to the external top absorbed dose of the clam shells
irradiated by x-ray at a dose of 3 kGy, as determined by the staff of NCEBFR. The
internal doses absorbed range from 1.8 kGy to 5.4 kGy, have a median of 4.0 kGy and
have a mean of 4.05 kGy. External top absorbed doses range from 1.7 kGy to 6.3 kGy,
have a median of 4.3 kGy and have a mean of 4.27 kGy.
The mean dose absorbed was also larger than the 3 kGy dose given as determined
by NCEBFR for both external and internal doses by more than 1kGy. In nine of the fifty
five clams irradiated at 3 kGy the internal absorbed dose is higher than the external top
absorbed dose. The external doses and internal doses are statistically significantly
48
different (P<0.05). External top dose mean is 0.22 kGy larger than the internal absorbed
dose mean. Linear regression of the data shows a positive relationship between external
dose and internal dose at a 95% confidence interval. Data for clams irradiated with x-ray
are more tightly grouped than oysters irradiated with x-ray. As discussed above the farm
raised clams are more uniform shell and are more similar to each other than the wild
oysters.
Figure 4-23 was created from the data in Table 6 and Table 14. Data in Figure 4-
23 show the percent external top shell x-ray dose absorbed internally in the clam shells as
compared to the mean thickness of the top shell of the clams. For mean thickness of the
top shell the range is 0.26 cm to 0.33 cm, the median is 0.29 cm and mean is 0.29 cm.
The percent external top shell dose absorbed internally range is 56% to 163%, the median
is 94% and the mean is 93%.
The data in Figure 4-23 are also very similar to the data found Figure 4-18. Both x-
ray and electron beam have similar spreads of percentage of external dose absorbed
internally. Linear regression of the data shows a positive relationship between the
percentage of external dose absorbed internally and the mean top shell thickness at a 95%
confidence interval. However, the R2 value for this data is only 0.0064 meaning that the
line is not a good fit for the data. Multiple linear regression models show no statistically
significant relationship (P≥0.05) between percentage of external dose absorbed internally
and the mean top shell thickness. It was expected that thickness would have a negative
relationship to percentage of external dose absorbed internally. The lack of a relationship
here may be due to the small range of thicknesses examined.
49
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5
Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-23. Percent external top shell dose absorbed internally in the clam shells as
compared to the mean thickness of the top shell of the clams irradiated at doses of 1kGy and 3 kGy with x-ray NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.7114x + 0.7226 R2 = 0.0064v).
Figure 4-24 was created from the data in Table 5 and Table 14. Data in Figure 4-
24 show the percent external top shell x-ray dose absorbed internally in the clam shells as
compared to the curvature of the top shell of the clams. For curvature of the top shell the
range is 0.26 to 0.39, the median is 0.33 and mean is 0.33. The percent external top shell
dose absorbed internally range from 70% to 117%, have a median of 98% and have a
mean of 96%.
Curvatures of clam shell examined in this research are very uniform. The clam
shell curvatures are less diverse than the oyster shells. A negative relationship is shown
between percentage of external dose absorbed internally and top shell curvature in linear
regression models with a confidence interval of 95% and a R2 value of 0.0006. However,
multiple linear regression models show no statistically significant relationship (P≥0.05)
between percentage of external dose absorbed internally and top shell curvature.
50
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-24. Percent external top shell dose absorbed internally in the clam shells as
compared to the curvature of the top shell of the clams irradiated at doses of 1kGy and 3 kGy with x-ray at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = -0.1797x + 0.9903 R2 = 0.0006).
Figure 4-25 was created from the data in Table 4 and Table 14. Data in Figure 4-
25 show the percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clams. For weight of the top shell the
range is 10.0g to 20.6g, the median is 13.0g and mean is 13.9g.
The percent external top shell dose absorbed internally range is 70% to 117%, the
median is 98% and the mean is 96%.
Linear regression shows a positive relationship between percentages of external
dose absorbed internally and top shell weight at a 95% confidence interval. The line does
not have a good fit however the R2 value is only 0.0064. No statistically significant
relationship (P≥0.05) exists between external dose absorbed internally and top shell
weight in multiple linear regression model. As with electron beam irradiated clams, x-
ray irradiated clams are not significantly affected by any of the factors we assessed.
51
Further experiments examining a larger range thicknesses, curvatures and weight may
provide different results. Measuring the shells microscopically may also provide
different results.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Top Shell Weight (g)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-25. Percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clam irradiated at doses of 1kGy and 3 kGy with x-ray NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.7114x + 0.7226 R2 = 0.0064).
Clam Irradiation with Gamma
A 60Co gamma source was also used in the irradiation of shucked clams. Clams
were harvested on May 11, 2005 from Cedar Key, irradiated with gamma at Food
Technology Inc. on July 6, 2005. The clams were shucked, measured, irradiated with
electron beam, irradiated with x-ray and loaded with dosimeter strips before irradiation
with gamma. After irradiation with gamma the dosimeter strips placed on the top clam
shell, bottom clam shell and in between the clam shells were read using
spectrophotometery.
52
Figure 4-26 was created from the data in Table 15. Data in Figure 4-26 show the
internal absorbed dose compared to the external top absorbed dose of the clam shells
irradiated by gamma at a dose of 1 kGy, as determined by the staff of Food Technology
Inc.. The internal doses range from 1.4 kGy to 3.1 kGy, have a median of 1.8 kGy and
have a mean of 1.88 kGy. External top absorbed doses range from 1.5 kGy to 3.3 kGy,
have a median of 2.0 kGy and have a mean of 2.09 kGy.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-26. The internal absorbed dose shucked clam shells as compared to the external
absorbed dose of the top shell of shucked clams after exposure to gamma at 1 kGy at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = 0.6135x + 0.6042 R2 = 0.6179).
The mean dose absorbed was larger than the 1kGy dose given as determined by
Food Technology Inc. for both external and internal dosimeters. For gamma the means
are closer than the means for electron beam or x-ray. The external doses and internal
doses are statistically significantly different (P<0.05) for clams irradiated at 1 kGy with
gammas. For only one of the forty five clams irradiated with gamma at 1 kGy the internal
absorbed dose is higher than the external top absorbed dose. External top dose mean is
53
0.21 kGy larger than the internal absorbed dose mean. Linear regression of the data
shows a positive relationship between external dose and internal dose at a 95%
confidence interval. The regression line is also a good fit with a R2 value of 0.6179.
Figure 4-27 was created from the data in Table 15. Data in Figure 4-27 show the
internal absorbed dose compared to the external top absorbed dose of the clam shells
irradiated by gamma at a dose of 3 kGy, as determined by the staff of Food Technology
Inc. The internal doses absorbed range from 1.5 kGy to 5.1 kGy, have a median of 4.3
kGy and have a mean of 4.24 kGy. External top absorbed doses range from 1.7 kGy to
5.2 kGy, have a median of 4.6 kGy and have a mean of 4.46 kGy.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-27. The internal absorbed dose of shucked clam shells as compared to the
external absorbed dose of the top shell of shucked clams after exposure to gamma at 3 kGy at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = 0.9134x + 0.152 R2 = 0.8344).
The external doses and internal doses are statistically significantly different
(P<0.05). None of the clams irradiated with gammas at 3 kGy have a internal dose higher
than the external dose. As with oysters gamma does not show the effects of a
54
concentration phenomenon. The external top dose mean is 0.22 kGy larger than the
internal absorbed dose mean. Data for clams irradiated with gamma are more tightly
grouped than data for clams irradiated with electron beam and x-ray. A positive
relationship between external dose and internal dose is shown by linear regression of the
data at a 95% confidence interval. The regression line is a good fit to the data with a R2
value equal to 0.8344.
Figure 4-28 was created from the data in Table 6 and Table 15. Data in Figure 4-
28 show the percent external top shell gamma dose absorbed internally in the clam shells
as compared to the mean thickness of the top shell of the clams. For mean thickness of
the top shell the range is 0.26 cm to 0.33 cm, the median is 0.29 cm and mean is 0.29 cm.
The percent external top shell dose absorbed internally range is 61% to 112%, the median
is 95% and the mean is 93%.
The shell thickness does not appear to affect the dose received in Figure 4-28. Data
in Figure 4-28 are more uniform than the data for electron beam (Figure 4-18) and the
data for x-ray (Figure 4-23). Linear regression of the data shows a negative relationship
between percentage of external dose absorbed internally and the mean top shell thickness
at a 95% confidence interval. However, the fit of the line is not good with a R2 value of
0.0485. Multiple linear regression of this data shows no statistically significant
relationship (P≥0.05) between percentage of external dose absorbed internally and the
mean top shell thickness. Thickness does not have a statistically significant effect on
percentage of external dose absorbed internally for electron beam, x-ray or gamma.
55
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5
Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-28. Percent external top shell dose absorbed internally in the clam shells as
compared to the mean thickness of the top shell of the clams irradiated at doses of 1 kGy and 3 kGy with gamma at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = -0.9988x + 1.2254 R2 = 0.0485).
Figure 4-29 was created from the data in Table 5 and Table 15. Data in Figure 4-
29 show the percent external top shell gamma dose absorbed internally in the clam shells
as compared to the curvature of the top shell of the clams. For curvature of the top shell
the range is 0.26 to 0.39, the median is 0.33 and mean is 0.33. The percent external top
shell dose absorbed internally for gamma irradiation range is 61% to 112%, the median is
95% and the mean is 93%. The data for the gamma (Figure 4-29) is more uniform than
the data for electron beam (Figure 4-19) and x-ray (Figure 4-24). A very small negative
relationship is exhibited with linear regression of the data at a 95% confidence interval.
With a R2 value of 0.0003 the regression line does not fit the data very well however. In
addition, multiple linear regression models of the data show no statistically significant
relationship (P≥0.05) between the percentage of external dose absorbed internally and the
56
top shell curvature. Curvature is also not a factor in determining the percentage of
external dose absorbed internally for electron beam, x-ray or gamma.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-29. Percent external top shell dose absorbed internally in the clam shells as
compared to the curvature of the top shell of the clams irradiated at doses of 1kGy and 3 kGy with gamma at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = -0.0652x + 0.9547 R2 = 0.0003).
Figure 4-30 was created from the data in Table 4 and Table 15. Data in Figure 4-
30 show the percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clams. For weight of the top shell the
range is 10.0g to 20.6g, the median is 13.0g and mean is 13.9g.
The percent external top shell dose absorbed internally range is 70% to 117%, the
median is 98% and the mean is 96%.
Linear regression shows a negative relationship between percentages of external
dose absorbed internally and top shell weight at a 95% confidence interval. The line does
not have a good fit however the R2 value is only 0.0485. No statistically significant
relationship (P<0.05) exists between external dose absorbed internally and top shell
57
weight in multiple linear regression models. Weight does not have a statistically
significant relationship to percentage of external dose absorbed internally for any of the
three irradiation sources
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Top Shell Weight (g)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-30. Percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clam irradiated at doses of 1kGy and 3 kGy with gamma Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = -0.9988x + 1.2254 R2 = 0.0485).
Clams irradiated with electron beam, x-ray or gamma have statistically
significantly different (P<0.05) external doses and internal doses. Percentage of external
dose absorbed internally is not affected by top shell thickness, curvature or weight in
clams irradiated with electron beam, x-ray of gamma. Data for gamma is more tightly
grouped than the data for electron beam or x-ray. Gamma also does not exhibit the
concentration effect that electron beam and x-ray exhibit. For these reasons gamma is the
most promising for irradiating clams industrially.
Future experiments on irradiation of clams are needed to assess the effectiveness of
irradiating clams on a large industrial scale. Experiments examining clams with a larger
58
range of thicknesses, curvatures and weights could also be performed in order to further
validate the results of this research. These experiments would increase the knowledge of
irradiation of shellfish.
Mussel Irradiation with Electron Beam
Electron beam was also used to irradiate mussels. Mussels were purchased on May
12, 2005, irradiated with electron beam at NCEBFR on June 8, 2005. The mussels were
shucked, measured and loaded with dosimeter strips before irradiation. After irradiation
the dosimeter strips placed on the top mussel shell, bottom mussel shell and in between
the mussel shells were read using spectrophotometery.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (kGy)
Inte
rnal
Dos
e (k
Gy)
Figure 4-31. The internal absorbed dose shucked mussel shells as compared to the
external absorbed dose of the top shell of shucked mussels after exposure to electron beam at 1 kGy at NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = -0.0271x + 1.6089 R2 = 0.0007).
Figure 4-31 was created from the data in Table 16. Data in Figure 4-31 show the
internal absorbed dose compared to the external top absorbed dose of the mussel shells
irradiated at a dose of 1 kGy, as determined by the staff of NCEBFR. . The doses
59
absorbed inside the mussel shells range from 1.2 kGy to 2.1 kGy, have a median of 1.5
kGy and have a mean of 1.57 kGy. External top absorbed doses range from 1.3 kGy to
2.3 kGy, have a median of 1.6 kGy and have a mean of 1.63 kGy.
The data for mussels irradiated with electron beam is more tightly grouped than the
data for clams and oysters irradiated with electron beam. The internal doses and external
doses for mussels irradiated at 1 kGy with electron beam are not statistically significantly
different (P≥0.05). Even though the means for external dose and internal dose are not
significantly different the data is far from ideal and not as tightly grouped as we would
like. In eleven of the forty seven mussels irradiated at 1 kGy the internal absorbed dose
is higher than the external top absorbed dose. The concentration phenomenon is also
exhibited in mussels as well as clams and mussels. External top dose mean is only 0.06
kGy larger than the internal absorbed dose mean. Linear regression of the data shows a
small negative relationship between the external and internal doses at a 95% confidence
interval. However, the regression line is not a good fit for the data with a R2 value equal
to 0.0007.
Figure 4-32 was created from the data in Table 16. Data in Figure 4-32 show the
internal absorbed dose compared to the external top absorbed dose of the mussel shells
irradiated at a dose of 3 kGy, as determined by the staff of NCEBFR. The internal doses
absorbed by the strips range from 1.3 kGy to 4.1 kGy, have a median of 3.1 kGy and
have a mean of 3.00 kGy. External top absorbed doses range from 1.7 kGy to 4.2 kGy,
have a median of 3.2 kGy and have a mean of 3.20 kGy.
60
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-32. The internal absorbed dose shucked mussel shells as compared to the
external absorbed dose of the top shell of shucked mussels after exposure at 3 kGy at NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = 0.5566x + 1.2022 R2 = 0.1406).
The external dose and internal dose are statistically significantly different (P<0.05).
The mean dose absorbed internally is 3.00 which is the target dose. Even with this ideal
mean there are thirteen of the fifty three mussels irradiated at 3 kGy with the internal
absorbed dose is higher than the external top absorbed dose. External top dose mean is
0.20 kGy larger than the internal absorbed dose mean. Linear regression of the data
shows a positive relationship between the external doses and internal doses at a
confidence interval of 95%. The regression line is not a very good fit to the data with a
R2 value of 0.1406. Even though the mean is exactly the dose we wanted the data is not
grouped as tightly as we would like to see. The concentration phenomenon also affects
24% of the mussels irradiated with 3 kGy.
61
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75
Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-33. Percent external top shell dose absorbed internally in the mussel shells as
compared to the mean thickness of the top shell of the mussels irradiated with electron beam at doses of 1kGy and 3 kGy NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = -0.2862x + 1.0008 R2 = 0.0179).
Figure 4-33 was created from the data in Table 9 and Table 16. Data in Figure 4-
33 show the percent external top shell dose absorbed internally in the mussel shells as
compared to the mean thickness of the top shell of the mussels. For mean thickness of
the top shell the range is 0.1cm to 0.62 cm, the median is 0.13 cm and mean is 0.15 cm.
The percent external top shell dose absorbed internally range is 41% to 150%, the median
is 94% and the mean is 96%.
The thicknesses of the top shells of the mussels are very similar. The percentage of
external dose absorbed internally covers a large rang and is not very uniform. Linear
regression of the data shows a negative relationship between the percentage of external
dose absorbed internally and mean top shell thickness at a 95% confidence interval.
However, the linear regression line is not a good fit with a R2 value of 0.0179. A
statistically significant relationship (P≥0.05) is not shown between percentage of external
62
dose absorbed internally and mean top shell thickness in multiple linear regression
models. Percent of external dose absorbed internally is not statistically significantly
affected by top shell thickness for mussels irradiated with electron beam. It was expected
that thickness would have a strong negative relationship to percentage of external dose
absorbed internally, as with oysters and clams.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-34. Percent external top shell dose absorbed internally in the mussel shells as
compared to the curvature of the top shell of the mussels irradiated at doses of 1kGy and 3 kGy NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = -0.6613x + 1.0962 R2 = 0.0248).
Figure 4-34 was created from the data in Table 8 and Table 16. Data in Figure 4-
34 show the percent external top shell dose absorbed internally in the mussel shells as
compared to the curvature of the top shell of the mussels. For curvature of the top shell
the range is 0.14 to 0.34, the median is 0.20 and mean is 0.21. The percent external top
shell dose absorbed internally range is 41% to 150%, the median is 94% and the mean is
96%.
63
The curvatures of the mussels (Figure 4-34) are more uniform than the curvatures
of the oysters (Figure 4-4), but are less uniform than the curvatures of the clams (Figure
4-19). A negative relationship is shown between percentage of external dose absorbed
internally and top shell curvature in linear regression models performed at a 95%
confidence interval. The fit of the line is not good with a R2 value of 0.0248 however.
Multiple linear regression models do not show a statistically significant relationship
(P≥0.05) between percentage of external dose absorbed internally and top shell curvature.
Figure 4-35 was created from the data in Table 7 and Table 16. Data in Figure 4-
35 show the percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clams. For weight of the top shell the
range is 2.0g to 6.8g, the median is 3.1g and mean is 3.2g.
The percent external top shell dose absorbed internally range is 41% to 150%, the
median is 94% and the mean is 95%.
Linear regression shows a small negative relationship between percentages of
external dose absorbed internally and top shell weight at a 95% confidence interval. The
line does not have a good fit however the R2 value is only 0.0013. No statistically
significant relationship (P≥0.05) exists between external dose absorbed internally and top
shell weight in multiple linear regression models.
The data for mussels irradiated with electron beam are very similar to the data for
oysters and clams irradiated with electron beam. All of the external doses and internal
doses of shellfish irradiated with electron beam are statistically significantly different
(P<0.05) except the mussels irradiated with electron beam at 1 kGy. Even with similar
means the data is not as tightly grouped as the data for gamma or x-ray. Electron beam
64
also exhibits the concentration phenomenon in all three species of shellfish investigated.
Top shell thickness, curvature and weight do not statistically significantly affect the
percentage of external dose absorbed internally in oysters, clams or mussels irradiated
with electron beam. Electron beam does not provide the uniformity of dose that we
would like for any of the three shellfish investigated.
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 1 2 3 4 5 6 7 8
Top Shell Wt (g)
Inte
rnal
/Top
Dos
e
Figure 4-35. Percent external top shell dose absorbed internally in the mussel shells as
compared to the weight of the top shell of the mussel irradiated at doses of 1kGy and 3 kGy with electron beam NCEBFR (6/8/05). Solid line shows linear regression of data with α=0.05 (y = -0.0074x + 0.9827 R2 = 0.0013).
There are numerous future experiments that may help us better understand how to
effectively use electron beam irradiation with shellfish. Irradiating shellfish on the half
shell may be a viable option for irradiating with electron beam. The concentration
phenomenon that is seen in electron beam also needs to be further investigated.
Experiments with different dosimetery methods, such as alanine dosimeters, may provide
a better understanding of this phenomenon. Future experiments may help to provide
better understanding and uses for electron beam.
65
Mussel Irradiation with X-ray
The second set of experiments for this research was performed with x-ray
irradiation of shucked mussels. Mussels were purchased on May 12, 2005, irradiated
with x-ray at NCEBFR on June 26, 2005. The mussels were shucked, measured,
irradiated with electron beam and loaded with dosimeter strips during the period in-
between. After irradiation with x-ray the dosimeter strips placed on the top mussel shell,
bottom mussel shell and in between the mussel shells were read using
spectrophotometery.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (kGy)
Inte
rnal
Dos
e (k
Gy)
Figure 4-36. The internal absorbed dose shucked mussel shells as compared to the
external absorbed dose of the top shell of shucked mussels after exposure to x-ray at 1 kGy at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.0799x + 1.6661 R2 = 0.004).
Figure 4-36 was created from the data in Table 17. Data in Figure 4-36 show the
internal absorbed dose compared to the external top absorbed dose of the mussel shells
irradiated by x-ray at a dose of 1 kGy, as determined by the staff of NCEBFR. The
internal doses absorbed by the strips range from 1.5 kGy to 2.2 kGy, have a median of
66
1.8 kGy and have a mean of 1.81 kGy. External top absorbed doses range from 1.6 kGy
to 2.1 kGy, have a median of 1.8 kGy and have a mean of 1.81 kGy.
The mean dose absorbed was larger than the 1kGy dose given as determined by
NCEBFR for both external and internal dosimeters. Both doses at 1 kGy and 3 kGy are
the same. The data in Figure 4-36 are much more uniform than the data for electron
beam. The external doses and internal doses of mussels irradiated at 1 kGy with x-ray
are not statistically significantly different (P≥0.05). As with mussels irradiated with
electron beam at 1 kGy the mean may be similar, but the data is not as tightly grouped as
with gamma. Fifteen of the forty seven mussels irradiated with x-ray at 1 kGy have an
internal absorbed dose that is higher than the external top absorbed dose. Linear
regression of the data at a 95% confidence interval shows a small positive relationship
between external dose and internal dose. With a R2 value of 0.004 the regression line is
not a good fit for the data however.
Figure 4-37 was created from the data in Table 17. Data in Figure 4-37 show the
internal absorbed dose compared to the external top absorbed dose of the mussel shells
irradiated by x-ray at a dose of 3 kGy, as determined by the staff of NCEBFR. The
internal doses absorbed by the strips range from 1.8 kGy to 5.0 kGy, have a median of
4.4 kGy and have a mean of 4.29 kGy. External top absorbed doses range from 1.6 kGy
to 5.2 kGy, have a median of 4.4 kGy and have a mean of 4.29 kGy.
The means of the internal doses and the external doses are equal. However, in
nineteen of the fifty three mussels irradiated at 3 kGy the internal absorbed dose is higher
than the external top absorbed dose. The concentration phenomenon is also seen in
mussels irradiated with x-ray. External doses and internal doses are not statistically
67
significantly different (P≥0.05). A positive relationship between external dose and
internal dose is shown by linear regression of the data at a 95% confidence interval. The
regression line is a good fit to the data with a R2 value of 0.8522. The data for mussels
irradiated with x-ray are more tightly grouped than the data for oysters or clams irradiated
with x-ray. Even though mussels irradiated with x-ray have means that are not
statistically significantly different (P≥0.05) the data is not as tightly grouped as the data
for mussels irradiated with gamma.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-37. The internal absorbed dose of shucked mussel shells as compared to the
external absorbed dose of the top shell of shucked mussels after exposure to x-ray at 3 kGy at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.842x + 0.6817 R2 = 0.8522).
Figure 4-38 was created from the data in Table 9 and Table 17. Data in Figure 4-
38 show the percent external top shell x-ray dose absorbed internally in the mussel shells
as compared to the mean thickness of the top shell of the mussels. For mean thickness of
the top shell the range is 0.1 cm to 0.62 cm, the median is 0.13 cm and mean is 0.15 cm.
68
The percent external top shell dose absorbed internally range is 79% to 122%, the median
is 100% and the mean is 100%.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75
Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-38. Percent external top shell dose absorbed internally in the mussel shells as
compared to the mean thickness of the top shell of the mussels irradiated at doses of 1kGy and 3 kGy with x-ray NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.2194x + 0.9718 R2 = 0.0408).
The mussel top shell thicknesses examined in this research did not cover a large
range. Linear regression of the data shows a positive relationship between the percentage
of external doses absorbed internally and the mean top shell thickness at a confidence
interval of 95%. Yet, the regression line does not fit the data very well with a R2 value of
0.0408. Multiple linear regressions of the data do not show a statistically significant
relationship (P≥0.05) between percentage of external doses absorbed internally and the
mean top shell thickness. Top shell thickness does not have a statistically significant
effect on the percentage of external dose absorbed internally for oysters, clams or mussels
irradiated with x-ray.
69
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-39. Percent external top shell dose absorbed internally in the mussel shells as
compared to the curvature of the top shell of the mussels irradiated at doses of 1kGy and 3 kGy with x-ray at NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.0654x + 0.9904 R2 = 0.0009).
Figure 4-39 was created from the data in Table 8 and Table 17. Data in Figure 4-
39 show the percent external top shell x-ray dose absorbed internally in the mussel shells
compared to the curvature of the top shell of the mussels. For curvature of the top shell
the range is 0.14 to 0.39, the median is 0.20 and mean is 0.21. The percent external top
shell dose absorbed internally range is 79% to 122%, the median is 100% and the mean is
100%.
The data for curvature are relatively uniform covering a small range except for one
offset data point. Although, the regression line is not a good fit with a R2 value of 0.0009
a positive relationship between percentage of external dose absorbed internally and top
shell curvature is seen in linear regression models at a 95% confidence interval. Multiple
linear regression of the data shows no statistically significant relationship (P≥0.05)
between the percentage of external dose absorbed internally and top shell curvature.
70
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 1 2 3 4 5 6 7 8 9 10
Top Shell Wt (g)
Inte
rnal
/Top
Dos
e
Figure 4-40. Percent external top shell dose absorbed internally in the mussel shells as
compared to the weight of the top shell of the mussel irradiated at doses of 1kGy and 3 kGy with x-ray NCEBFR (6/26/05). Solid line shows linear regression of data with α=0.05 (y = 0.0033x + 0.9933 R2 = 0.001).
Figure 4-40 was created from the data in Table 7 and Table 17. Data in Figure 4-
40 show the percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clams. For weight of the top shell the
range is 2.0g to 6.8g, the median is 3.1g and mean is 3.2g. The percent external top shell
dose absorbed internally range is 79% to 122%, the median is 100% and the mean is
100%.
Linear regression shows a small negative relationship between percentages of
external dose absorbed internally and top shell weight at a 95% confidence interval. The
line does not have a good fit however the R2 value is only 0.001. No statistically
significant relationship (P≥0.05) exists between external dose absorbed internally and top
shell weight in multiple linear regression models.
71
Unlike oysters and clams, mussels irradiated with x-ray are not statistically
significantly different (P≥0.05). The data for mussels irradiated with x-ray are more
tightly grouped than the data for oysters or clams irradiated with x-ray. Top shell
thickness, curvature and weight are also not statistically significantly affecting the
percentage of external dose absorbed internally for any of the three species of shellfish
irradiated with x-ray. Although x-ray does exhibit the concentration phenomenon in all
of the shellfish investigated, x-ray may be a viable option for irradiating mussels. Future
experiments are needed to further expand the knowledge on irradiation of mussels.
Experiments with different dosimetry methods may provide a better understanding of the
concentration effect seen in the shellfish irradiated with x-ray.
Mussel Irradiation with Gamma
A gamma source was also used to irradiate the oysters. Mussels were purchased on
May 12, 2005, irradiated with gamma at Food Technology Inc. on July 6, 2005. The
mussels were shucked, measured, irradiated with electron beam, irradiated with x-ray and
loaded with dosimeter strips before irradiation with gamma. After irradiation with
gamma the dosimeter strips placed on the top mussel shell, bottom mussel shell and in
between the mussel shells were read using spectrophotometery.
Figure 4-41 was created from the data in Table 18. Data in Figure 4-41 show the
internal absorbed dose compared to the external top absorbed dose of the mussel shells
irradiated by gamma at a dose of 1 kGy, as determined by the staff of Food Technology
Inc. The internal doses range from 1.6 kGy to 2.0 kGy, have a median of 1.7 kGy and
have a mean of 1.73 kGy. External top absorbed doses range from 1.6 kGy to 2.2 kGy,
have a median of 1.9 kGy and have a mean of 1.89 kGy.
72
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (kGy)
Inte
rnal
Dos
e (k
Gy)
Figure 4-41. The internal absorbed dose shucked mussel shells as compared to the
external absorbed dose of the top shell of shucked mussels after exposure to gamma at 1 kGy at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = 0.4832x + 0.813 R2 = 0.3341).
The mean dose absorbed was larger than the 1kGy dose given as determined by
Food Technology Inc. for both external and internal dosimeters. External doses and
internal doses are statistically significantly different (P<0.05) for mussels irradiated at 1
kGy with gammas. None of the forty seven mussels irradiated with gamma at 1 kGy have
an internal absorbed dose higher than the external top absorbed dose. The gammas do
not appear to have the concentration effect with in the shell that the electron beam and x-
rays have. External top dose mean is 0.16 kGy larger than the internal absorbed dose
mean. Linear regression of the data shows a positive relationship between external dose
and internal dose with a R2 value of 0.3341 at a confidence interval of 95%.
Figure 4-42 was created from the data in Table 18. Data in Figure 4-42 show the
internal absorbed dose compared to the external top absorbed dose of the mussel shells
irradiated by gamma at a dose of 3 kGy, as determined by the staff of Food Technology
73
Inc. The internal doses absorbed range from 1.6 kGy to 5.0 kGy, have a median of 4.4
kGy and have a mean of 4.23 kGy. External top absorbed doses range from 1.8 kGy to
5.0 kGy, have a median of 4.5 kGy and have a mean of 4.36 kGy.
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
External Dose (Kgy)
Inte
rnal
Dos
e (K
gy)
Figure 4-42. The internal absorbed dose of shucked mussel shells as compared to the
external absorbed dose of the top shell of shucked mussels after exposure to gamma at 3 kGy at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = 0.9897x - 0.0884 R2 = 0.9634).
The data for mussels irradiated with gamma are tightly fit along a straight line and
clearly show the linear relation between internal dose and external dose. Zero of the
mussels irradiated with gamma at 3 kGy have an internal absorbed dose that is higher
than the external top absorbed dose. External top dose mean is 0.13 kGy larger than the
internal absorbed dose mean. Mussels irradiated at 3 kGy with gammas have
statistically significantly different (P<0.05) external doses and internal doses. Linear
regression of the data shows a positive relationship between the external and internal
doses at a 95% confidence interval. The regression line is almost a perfect fit for this
74
data with a R2 value of 0.9634. Gamma shows the tightly grouped relationship that we
want when irradiating shellfish.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75
Mean Top Shell Thickness (cm)
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-43. Percent external top shell dose absorbed internally in the mussel shells as
compared to the mean thickness of the top shell of the mussels irradiated at doses of 1 kGy and 3 kGy with gamma at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = -0.0671x + 0.953 R2 = 0.0108).
Figure 4-43 was created from the data in Table 9 and Table 18. Data in Figure 4-
43 show the percent external top shell gamma dose absorbed internally in the mussel
shells as compared to the mean thickness of the top shell of the mussels. For mean
thickness of the top shell the range is 0.1 cm to 0.62 cm, the median is 0.13 cm and mean
is 0.15 cm. The percent external top shell dose absorbed internally range is 80% to
100%, the median is 95% and the mean is 94%.
The shell thickness does not appear to affect the dose received in Figure 4-43. Data
in Figure 4-43 are more uniform than the data for electron beam (Figure 4-33) and the
data for x-ray (Figure 4-38). Linear regression of the data shows a small negative
relationship between percentage of external dose absorbed internally and the mean top
75
shell thickness at a 95% confidence interval. However, the regression line is not a good
fit for the data with a R2 value of 0.0108. Multiple linear regression models do not shows
a statistically significant relationship (P≥0.05) between percentage of external dose
absorbed internally and the mean top shell thickness. None of the three species of
shellfish examined in this research show a statistically significant relationship (P≥0.05)
between top shell thickness and the percentage of external dose absorbed internally.
00.10.20.30.40.50.60.70.80.9
11.11.21.31.41.5
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Top Shell Curvature
Inte
rnal
/Ext
erna
l Dos
e (%
)
Figure 4-44. Percent external top shell dose absorbed internally in the mussel shells as
compared to the curvature of the top shell of the mussels irradiated at doses of 1kGy and 3 kGy with gamma at Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = 0.1562x + 0.9108 R2 = 0.0152).
Figure 4-44 was created from the data in Table 8 and Table 18. Data in Figure 4-
44 shows the percent external top shell gamma dose absorbed internally in the mussel
shells as compared to the curvature of the top shell of the mussels. For curvature of the
top shell the range is 0.11 to 0.88, the median is 0.23 and mean is 0.24. The percent
external top shell dose absorbed internally for gamma irradiation range is 74% to 100%,
the median is 95% and the mean is 93%.
76
The data for the gamma (Figure 4-44) is more uniform than the data for electron
beam (Figure 4-34) and x-ray (Figure 4-39). Linear regression of the data shows a
positive relationship between the percentage of external dose absorbed internally and the
top shell curvature at a 95% confidence level. No statistically significant relationship
(P≥0.05) is shown between the percentage of external dose absorbed internally and the
top shell curvature in multiple linear regression models. Curvature does not affect the
percentage of external dose absorbed internally for oysters, clams or mussels.
Figure 4-45 was created from the data in Table 7 and Table 18. Data in Figure 4-
45 show the percent external top shell dose absorbed internally in the clam shells as
compared to the weight of the top shell of the clams. For weight of the top shell the
range is 2.0g to 6.8g, the median is 3.1g and mean is 3.2g. The percent external top shell
dose absorbed internally range is 74% to 100%, the median is 94% and the mean is 93%.
Linear regression shows a small negative relationship between percentages of external
dose absorbed internally and top shell weight at a 95% confidence interval. The line does
not have a good fit however the R2 value is only 0.0118. No statistically significant
relationship (P≥0.05) exists between external dose absorbed internally and top shell
weight in multiple linear regression models. Top shell weight does not have a significant
affect on the percentage of external dose absorbed internally for any of the three shellfish
examined.
The external doses and internal doses are statistically significantly different for the
oysters, clams and mussels irradiated with gamma. However, gamma also provided the
most tightly grouped data of all of the three irradiation sources tested. This is as to be
expected due to the higher energy and therefore the higher penetration of gamma
77
irradiation. Top shell thickness, curvature and weight do not have a statistically
significant relationship (P≥0.05) to percentage of external dose absorbed internally for
any of the species of shellfish investigated in this research. Gamma is the most
promising of the three types of irradiation studied for irradiating oysters, clams, and
mussels.
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 1 2 3 4 5 6 7 8 9 10
Top Shell Wt (g)
Inte
rnal
/Top
Dos
e
Figure 4-45. Percent external top shell dose absorbed internally in the mussel shells as
compared to the weight of the top shell of the mussel irradiated at doses of 1kGy and 3 kGy with gamma Food Technology Inc. (7/6/05). Solid line shows linear regression of data with α=0.05 (y = 0.0068x + 0.9214 R2 = 0.0118).
Oysters have the least tightly grouped data of the three shellfish studied for electron
beam, x-ray and gamma. Data for clams are not as tightly grouped as data for mussels
irradiated with electron beam, x-ray and gamma. This data confirms what we expected.
Mussel should have the most uniform irradiation results since they have the thinnest and
most uniform shells of the shellfish investigated. Irradiation data for clams are less
uniform than mussels due to their thicker and less uniform shells and oysters have the
least uniform irradiation data since their shells are the thickest and least uniform.
78
However, when the shell geometry and weight are investigated for the three shellfish it is
determined that shell thickness, curvature and weight do not statistically significantly
affect the percentage of external dose absorbed internally in oysters, clams and mussels
irradiated with electron beam, x-ray and gamma. It was expected that thickness,
curvature and weight would all have an effect on percentage of external dose absorbed
internally in oysters, clams and mussels. One reason for this may be another more
important factor overshadowing the effects thickness, curvature and weight. Another
reason for this unexpected result may be the technique used to measure the shells. The
shells were all measured on a macroscopic scale, yet the diverse landscape of the shell
may yield better results if the shell is examined microscopically. These are all possible
explanations for the unexpected results in these experiments.
Gamma is the most promising of the three sources of irradiation studied. The most
tightly grouped data is provided by gamma for oysters, clams and mussels. X-ray
provides tighter grouped data than electron beam does. This is as expected. The energy
and penetration of gammas are the highest, x-rays have the next highest energy and
penetration and electron beam have the lowest energy and penetration. X-ray and
electron beam exhibit the concentration phenomenon where the internal dose is higher
than the applied external dose. It is for these reasons and others that gamma irradiation is
the most viable source for irradiating shellfish on a large industrial scale.
This research creates questions that should be answered by future research. First,
different dosimeters could be used to help clarify the data presented in this research. The
use of different dosimetry may also help to clarify the concentration phenomenon that is
seen with electron beam and x-ray. Also future experiments should be performed with
79
microscopic measuring techniques to examine thickness and curvature. As mentioned
above experiments with shellfish on the half shell may be promising for electron beam
and x-ray since the shell is not present as a barrier. Large scale experiments, using tons
of shellfish, with gamma irradiation should also be performed to determine the
penetration of dose in pallets of shellfish. Economic experiments to compare electron
beam, x-ray and gamma may also provide valuable information about the practicality of
large scale irradiation of shellfish. With the help of experiments such as these irradiation
of shellfish may become viable industrial practice.
80
CHAPTER 5 SUMMARY AND CONCLUSIONS
The primary objective of this research was to compare and contrast the percentage
of absorption of irradiation in oyster, clam and mussel shells using gamma, electron beam
and x-ray irradiation sources at dosages of 1 kGy and 3 kGy. Oyster, clam and mussel
shells were assessed for differences in external absorbed dose and internal absorbed dose
for electron beam, x-ray and gamma sources. Furthermore, the thickness, weight and
curvatures for oyster, clam and mussel shells were assessed with respect to the effect on
percentage of applied dose absorbed internally.
When clam and oyster shells were irradiated using gamma, x-ray or electron beam
at 1 kGy and 3 kGy, the absorbed internal dose was less than the external dose and was
determined to be significantly different (P<0.05) when compared to the external absorbed
shell dose. When mussel shells were irradiated using electron beam at 1 kGy or x-ray at
1 kGy and 3 kGy no statistical significant differences (P≥0.05) were determined to exist
between the external and internal absorbed dose. However, when mussel shells were
irradiated with electron beam at 3 kGy and gamma irradiation at 1 kGy and 3 kGy,
significant differences (P<0.05) were determined to exist between the external and
internal absorbed doses. When oyster, clam and mussel shells were irradiated with
electron beam and x-ray a concentration phenomenon, where internal doses were greater
than the external doses, was exhibited. Specifically, the concentration phenomenon was
exhibited in 12% of the oyster shells, 12% of the clam shells and 24% of the mussel
shells irradiated with electron beam. The concentration phenomenon was exhibited in
81
14% of the oyster shells, 17% of the clam shells and 34% of the mussel shells irradiated
with x-ray.
When top shell thickness, weight and curvature for oyster, clam and mussel shells
were statistically compared to the percentage ratio of external/internal absorbed dose, no
significant relationship (P≥0.05) was revealed. Specifically, no statistical relationship
was demonstrated between the percentage external dose absorbed internally and the top
shell thickness, curvature of the shell and weight of the shell using electron beam, x-ray
and gamma at 1 kGy and 3 kGy. Therefore, oyster, clam and mussel shell thickness,
shell curvature and shell weight did not have a statistical significant relationship or
influence on the percentage of external/internal absorbed dose at 1 kGy and 3 kGy.
Reasons for the differences between external and internal absorbed doses and
concentration phenomenon are unclear and can not be accounted for by differences in
shell thickness, shell weight or shell curvature.
82
APPENDIX A OYSTER, CLAM, AND MUSSEL MEASUREMENTS
Oyster Measurements
Table A-1. Oyster Weight Measurements in g (5/1/05) Oyster Overall
wt Meat wt
Shell wt
Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
1 84.2 16.1 68.1 47.3 20.8 4.23 2.27 2.94 1.29 2 67.8 6.1 61.7 30.4 31.3 10.11 0.97 4.98 5.13 3 59.1 5.9 53.2 32.1 21.1 9.02 1.52 5.44 3.58 4 55.5 6.8 48.7 29.5 19.2 7.16 1.54 4.34 2.82 5 37.0 4.2 32.8 19.4 13.4 7.81 1.45 4.62 3.19 6 64.1 8.0 56.1 33.3 22.8 7.01 1.46 4.16 2.85 7 41.2 3.6 37.6 20.8 16.8 10.44 1.24 5.78 4.67 8 57.7 4.5 53.2 39.8 13.4 11.82 2.97 8.84 2.98 9 91.8 12.4 79.4 48.3 31.1 6.40 1.55 3.90 2.51 10 72.5 11.8 60.7 37.5 23.2 5.14 1.62 3.18 1.97 11 50.9 8.0 42.9 26.4 16.5 5.36 1.60 3.30 2.06 12 47.1 5.6 41.5 23 18.5 7.41 1.24 4.11 3.30 13 56.3 7.6 48.7 32.6 16.1 6.41 2.02 4.29 2.12 14 45.0 6.0 39.0 23.4 15.6 6.50 1.50 3.90 2.60 15 63.7 9.2 54.5 32.2 22.3 5.92 1.44 3.50 2.42 16 107.8 15.9 91.9 53.7 38.2 5.78 1.41 3.38 2.40 17 105.1 12.6 92.5 49.6 42.9 7.34 1.16 3.94 3.40 18 59.6 7.3 52.3 30.4 21.9 7.16 1.39 4.16 3.00 19 66.7 9.5 57.2 35.8 21.4 6.02 1.67 3.77 2.25 20 64.7 10.0 54.7 33.7 21.0 5.47 1.60 3.37 2.10 21 138.9 17.3 121.6 76.2 45.4 7.03 1.68 4.40 2.62 22 48.9 7.9 41.0 22.9 18.1 5.19 1.27 2.90 2.29 23 57.8 7.9 49.9 31.9 18.0 6.32 1.77 4.04 2.28 24 70.8 9.0 61.8 36.1 25.7 6.87 1.40 4.01 2.86 25 81.9 11.6 70.3 42.2 28.1 6.06 1.50 3.64 2.42 26 41.5 6.2 35.3 18.7 16.6 5.69 1.13 3.02 2.68 27 47.0 7.1 39.9 24.3 15.6 5.62 1.56 3.42 2.20 28 63.0 12.0 51.0 32.7 18.3 4.25 1.79 2.73 1.53 29 83.2 13.9 69.3 47.4 21.9 4.99 2.16 3.41 1.58 30 57.0 9.3 47.7 33.2 14.5 5.13 2.29 3.57 1.56 31 43.6 5.1 38.5 22.2 16.3 7.55 1.36 4.35 3.20 32 81.6 8.7 72.9 45.7 27.2 8.38 1.68 5.25 3.13 33 57.0 6.3 50.7 29.7 21.0 8.05 1.41 4.71 3.33 34 57.7 8.0 49.7 30.9 18.8 6.21 1.64 3.86 2.35 35 58.5 8.4 50.1 32.8 17.3 5.96 1.90 3.90 2.06 36 86.9 11.1 75.8 44.5 31.3 6.83 1.42 4.01 2.82 37 44.5 4.0 40.5 28 12.5 10.13 2.24 7.00 3.13 38 56.1 8.3 47.8 33.5 14.3 5.76 2.34 4.04 1.72 39 59.4 10.2 49.2 29.9 19.3 4.82 1.55 2.93 1.89 40 45.5 9.1 36.4 24.3 12.1 4.00 2.01 2.67 1.33
83
Table A-1. Continued Oyster Overall
wt Meat wt
Shell wt
Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
41 41.0 6.8 34.2 21.5 12.7 5.03 1.69 3.16 1.87 42 45.4 7.1 38.3 20.1 18.2 5.39 1.10 2.83 2.56 43 54.0 8.8 45.2 26.8 18.4 5.14 1.46 3.05 2.09 44 62.5 6.6 55.9 35.5 20.4 8.47 1.74 5.38 3.09 45 55.6 10.8 44.8 27.8 17.0 4.15 1.64 2.57 1.57 46 39.1 7.0 32.1 19.3 12.8 4.59 1.51 2.76 1.83 47 65.0 14.9 50.1 32.3 17.8 3.36 1.81 2.17 1.19 48 57.0 15.5 41.5 25.9 15.6 2.68 1.66 1.67 1.01 49 83.8 9.2 74.6 48.0 26.6 8.11 1.80 5.22 2.89 50 53.5 11.0 42.5 29.0 13.5 3.86 2.15 2.64 1.23 51 69.2 8.6 60.6 39.1 21.5 7.05 1.82 4.55 2.50 52 54.3 10.7 43.6 27.8 15.8 4.07 1.76 2.60 1.48 53 37.3 5.7 31.6 20.7 10.9 5.54 1.90 3.63 1.91 54 48.9 6.9 42.0 30.0 12.0 6.09 2.50 4.35 1.74 55 48.8 6.2 42.6 24.7 17.9 6.87 1.38 3.98 2.89 56 34.2 5.9 28.3 17.3 11.0 4.80 1.57 2.93 1.86 57 42.2 6.0 36.2 21.0 15.2 6.03 1.38 3.50 2.53 58 66.6 12.7 53.9 34.6 19.3 4.24 1.79 2.72 1.52 59 54.8 4.6 50.2 28.8 21.4 10.91 1.35 6.26 4.65 60 54.0 8.2 45.8 29.1 16.7 5.59 1.74 3.55 2.04 61 63.5 8.8 54.7 29.4 25.3 6.22 1.16 3.34 2.88 62 67.0 6.2 60.8 36.0 24.8 9.81 1.45 5.81 4.00 63 63.7 13.4 50.3 32.5 17.8 3.75 1.83 2.43 1.33 64 129.2 12.5 116.7 69.3 47.4 9.34 1.46 5.54 3.79 65 50.1 6.6 43.5 27.2 16.3 6.59 1.67 4.12 2.47 66 80.7 10.5 70.2 42.7 27.5 6.69 1.55 4.07 2.62 67 48.8 9.0 39.8 22.1 17.7 4.42 1.25 2.46 1.97 68 73.6 9.6 64.0 48.7 15.3 6.67 3.18 5.07 1.59 69 108.3 14.0 94.3 65.6 28.7 6.74 2.29 4.69 2.05 70 87.3 9.2 78.1 46.0 32.1 8.49 1.43 5.00 3.49 71 65.6 10.6 55.0 35.5 19.5 5.19 1.82 3.35 1.84 72 108.6 12.6 96.0 62.0 34.0 7.62 1.82 4.92 2.70 73 51.7 9.8 41.9 25.5 16.4 4.28 1.55 2.60 1.67 74 42.3 8.6 33.7 19.8 13.9 3.92 1.42 2.30 1.62 75 65.5 10.1 55.4 34.7 20.7 5.49 1.68 3.44 2.05 76 60.1 7.6 52.5 27.4 25.1 6.91 1.09 3.61 3.30 77 54.4 6.9 47.5 28.2 19.3 6.88 1.46 4.09 2.80 78 65.9 10.1 55.8 30.6 25.2 5.52 1.21 3.03 2.50 79 136.8 24.4 112.4 71.9 40.5 4.61 1.78 2.95 1.66 80 81.7 9.8 71.9 39.8 32.1 7.34 1.24 4.06 3.28 81 55.0 8.9 46.1 25.3 20.8 5.18 1.22 2.84 2.34 82 64.1 12.0 52.1 30.6 21.5 4.34 1.42 2.55 1.79 83 59.3 7.5 51.8 32.4 19.4 6.91 1.67 4.32 2.59 84 80.6 13.3 67.3 46.1 21.2 5.06 2.17 3.47 1.59 85 70.5 15.3 55.2 29.2 26.0 3.61 1.12 1.91 1.70 86 55.9 10.9 45.0 29.3 15.7 4.13 1.87 2.69 1.44 87 42.9 9.2 33.7 20.1 13.6 3.66 1.48 2.18 1.48 88 96.4 11.1 85.3 45.0 40.3 7.68 1.12 4.05 3.63 89 62.7 9.8 52.9 32.7 20.2 5.40 1.62 3.34 2.06 90 114.7 13.9 100.8 63.1 37.7 7.25 1.67 4.54 2.71
84
Table A-1. Continued Oyster Overall
wt Meat wt
Shell wt
Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
91 84.3 13.0 71.3 43.9 27.4 5.48 1.60 3.38 2.11 92 52.5 9.6 42.9 22.4 20.5 4.47 1.09 2.33 2.14 93 72.5 8.2 64.3 39.8 24.5 7.84 1.62 4.85 2.99 94 59.3 11.4 47.9 29.5 18.4 4.20 1.60 2.59 1.61 95 38.3 6.9 31.4 18.3 13.1 4.55 1.40 2.65 1.90 96 57.7 10.3 47.4 30.5 16.9 4.60 1.80 2.96 1.64 97 68.7 10.4 58.3 35.2 23.1 5.61 1.52 3.38 2.22 98 55.1 10.7 44.4 28.2 16.2 4.15 1.74 2.64 1.51 99 57.5 9.5 48.0 28.0 20.0 5.05 1.40 2.95 2.11 100 50.4 8.8 41.6 21.8 19.8 4.73 1.10 2.48 2.25
Table A-2. Oyster Dimension Measurements in cm (5/3/05) Oyster
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
1 10.6 2.2 5.8 8.3 0.65 4.85 10.6 2.85 5.8 2 6.5 1.65 6.1 5.6 1.05 5.3 6.5 2.7 6.1 3 7.3 1.5 4.5 5.05 0.8 3.65 7.3 2.3 4.5 4 6.3 2.1 6.0 4.8 1.0 5.15 6.3 3.1 6.0 5 6.2 1.3 4.1 5.3 0.9 3.6 6.2 2.2 4.1 6 6.75 1.4 4.8 5.7 1.1 3.9 6.75 2.5 4.8 7 5.8 1.55 4.5 5.15 1.0 3.8 5.8 2.55 4.5 8 6.3 1.5 4.0 5.5 1.05 3.7 6.3 2.55 4.0 9 6.5 0.7 4.7 5.5 1.2 3.9 6.5 1.9 4.7 10 9.4 2.0 4.7 7.5 0.65 4.45 9.4 2.65 4.7 11 7.6 1.6 5.2 6.3 0.45 4.45 7.6 2.05 5.2 12 6.6 1.85 4.75 6.05 1.05 4.15 6.6 2.9 4.75 13 8.2 2.0 4.9 6.7 0.7 4.1 8.2 2.7 4.9 14 7.8 1.6 3.7 6.7 0.65 3.5 7.8 2.25 3.7 15 7.7 1.65 3.95 7.15 0.8 4.1 7.7 2.45 3.95 16 8.4 1.75 7.45 7.1 1.45 5.4 8.4 3.2 7.45 17 8.65 1.85 5.2 7.35 1.5 4.65 8.65 3.35 5.2 18 6.3 1.8 5.6 5.8 0.95 5.1 6.3 2.75 5.6 19 8.4 2.3 4.9 7.35 1.0 4.15 8.4 3.3 4.9 20 7.69 2.0 5.2 6.9 0.8 4.6 7.69 2.8 5.2 21 9.0 2.0 5.2 6.9 0.8 4.6 9.0 2.8 5.2 22 4.45 1.9 3.9 5.3 0.6 3.7 5.3 2.5 3.9 23 7.5 2.3 5.3 5.7 0.9 4.45 7.5 3.2 5.3 24 7.0 1.2 4.75 6.1 1.2 4.05 7.0 2.4 4.75 25 8.4 2.3 4.9 7.35 1.0 4.15 8.4 3.3 4.9 26 6.0 1.4 4.4 5.15 0.9 4.2 6.0 2.3 4.4 27 6.75 1.5 4.9 5.95 0.65 3.85 6.75 2.15 4.9 28 8.8 2.2 5.75 6.8 0.65 4.55 8.8 2.85 5.75 29 9.4 2.1 4.1 8.9 1.0 3.4 9.4 3.1 4.1 30 9.2 1.35 3.9 6.85 0.95 3.4 9.2 2.3 3.9 31 9.05 1.45 4.3 7.2 0.6 3.45 9.05 2.05 4.3 32 6.1 1.6 6.15 6.05 1.0 4.75 6.1 2.6 6.15 33 5.8 1.9 4.1 6.0 0.65 4.3 6.0 2.55 4.3 34 7.65 2.1 4.4 6.7 0.6 4.05 7.65 2.7 4.4 35 7.65 2.1 4.4 6.7 0.6 4.05 4.68 2.7 4.4 36 7.8 1.7 5.6 6.5 1.2 4.5 7.8 2.9 5.6
85
Table A-2. Continued Oyster
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
37 8.3 2.5 4.75 6.2 0.9 3.8 8.3 3.4 4.75 38 7.7 1.9 3.7 6.4 0.6 3.1 7.7 2.5 3.7 39 9.3 1.45 4.8 8.3 0.6 4.15 9.3 2.05 4.8 40 8.8 1.7 4.2 7.15 0.6 3.55 8.8 2.3 4.2 41 7.5 1.7 3.7 6.85 0.3 3.15 7.5 2.0 3.7 42 6.8 1.5 5.1 5.15 1.0 4.1 6.8 2.5 5.1 43 6.95 1.7 5.1 5.75 1.0 4.0 6.95 2.7 5.1 44 8.3 1.75 2.9 6.3 0.7 2.8 8.3 2.45 2.9 45 6.4 2.4 4.5 5.15 0.95 3.55 6.4 3.35 4.5 46 6.9 1.5 4.0 6.2 0.55 3.4 6.9 2.05 4.0 47 8.79 1.9 5.65 7.4 0.5 4.3 8.79 2.4 5.65 48 7.9 1.95 5.5 5.5 0.7 4.1 7.9 2.65 5.5 49 6.15 1.4 5.5 5.95 1.1 4.0 6.15 2.5 5.5 50 8.9 1.6 4.4 7.5 0.5 3.4 8.9 2.1 4.4 51 8.9 2.2 5.6 7.5 .55 4.6 8.9 2.75 5.6 52 8.7 1.9 5.4 6.8 0.45 4.15 8.7 2.35 5.4 53 9.7 1.8 3.8 7.0 0.55 3.0 9.7 2.35 3.8 54 6.65 1.75 3.75 5.3 0.6 3.0 6.65 2.35 3.75 55 5.65 1.6 5.6 4.9 0.75 3.7 5.65 2.35 5.6 56 8.85 1.15 3.65 6.6 0.55 3.3 8.85 1.7 3.65 57 6.3 1.5 4.85 5.2 0.75 3.95 6.3 2.25 4.85 58 8.45 1.7 7.05 6.9 0.75 4.3 8.45 2.45 7.05 59 6.9 1.45 4.5 6.0 1.1 3.9 6.9 2.55 4.5 60 8.75 2.0 4.75 7.1 1.15 2.7 8.75 3.15 4.75 61 8.8 1.35 4.5 7.5 0.75 3.55 8.8 2.1 4.5 62 6.2 1.6 5.1 5.4 1.75 3.9 6.2 3.35 5.1 63 9.85 2.75 5.1 7.75 0.6 4.2 9.85 3.35 5.1 64 8.5 1.6 6.5 7.2 1.2 6.0 8.5 2.8 6.5 65 6.55 1.7 3.6 5.05 0.8 3.1 6.55 2.5 3.6 66 7.1 2.1 5.75 6.1 1.0 4.9 7.1 3.1 5.75 67 7.1 1.6 4.8 5.8 0.6 3.5 7.1 2.2 4.8 68 7.8 2.55 4.8 6.7 0.5 4.2 7.8 3.05 4.8 69 9.35 2.15 6.0 7.5 .85 4.75 9.35 3.0 6.0 70 9.3 1.45 5.3 6.7 70 4.4 9.3 71.45 5.3 71 9.5 1.8 4.4 6.85 0.6 4.0 9.5 2.4 4.4 72 8.85 1.5 5.75 8.25 0.8 4.9 8.85 2.3 5.75 73 9.15 1.3 3.9 7.65 0.5 3.5 9.15 1.8 3.9 74 6.8 1.7 4.6 7.2 0.55 3.7 7.2 2.25 4.6 75 8.85 1.45 4.6 5.65 0.45 3.7 8.85 1.9 4.6 76 6.3 1.45 4.45 5.85 0.9 4.1 6.3 2.35 4.45 77 6.6 1.6 5.15 5.6 0.9 3.7 6.6 2.5 5.15 78 8.75 1.55 4.9 7.4 0.9 3.6 8.75 2.45 4.9 79 8.6 2.6 5.6 7.7 1.8 4.8 8.6 4.4 5.6 80 7.6 1.9 5.2 6.55 1.45 4.4 7.6 3.35 5.2 81 6.9 1.6 5.0 5.8 1.15 4.1 6.9 2.75 5.0 82 8.65 1.9 5.0 7.0 1.7 4.9 8.65 3.6 5.0 83 7.3 2.4 4.45 5.75 0.7 3.9 7.3 3.1 4.45 84 8.8 1.85 4.55 6.5 0.9 4.2 8.8 2.75 4.55 85 10.5 1.6 5.35 10.2 0.5 4.3 10.5 2.1 5.35 86 7.1 1.6 4.4 5.4 0.85 4.0 7.1 2.45 4.4
86
Table A-2. Continued Oyster
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
87 7.65 1.75 4.4 5.9 0.65 3.9 7.65 2.4 4.4 88 7.4 2.3 5.0 6.8 1.55 4.05 7.4 3.85 5.0 89 7.65 1.55 4.8 6.55 0.55 4.15 7.65 2.1 4.8 90 9.8 2.1 6.3 7.8 0.85 4.75 9.8 2.95 6.3 91 10.35 2.95 5.0 8.75 0.9 4.05 10.35 3.85 5.0 92 8.6 .95 4.7 6.85 0.55 4.3 8.6 1.5 4.7 93 7.95 7.0 6.0 6.3 0.8 4.95 7.95 7.8 6.0 94 8.1 1.9 4.3 6.9 0.5 3.8 8.1 2.4 4.3 95 7.4 1.5 3.5 5.8 0.5 3.25 7.4 2.0 3.5 96 6.9 2.1 4.4 5.6 0.9 4.1 6.9 3.0 4.4 97 9.0 1.9 5.05 6.9 1.0 4.6 9.0 2.9 5.05 98 8.3 2.1 4.3 6.45 0.6 3.85 8.3 2.7 4.3 99 7.9 2.0 4.35 6.6 0.55 3.8 7.9 2.55 4.35 100 5.7 1.75 4.3 5.35 1.75 4.0 5.7 3.5 4.3 Table A-3. Oyster Thickness Measurements in cm (5/4/05) Oyster 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom 1 0.231 0.318 0.724 0.533 0.373 0.292 0.277 0.269 0.282 0.470 2 0.445 0.559 0.803 0.658 0.457 0.533 0.302 0.521 0.645 0.287 3 0.221 0.414 0.696 0.635 0.277 0.279 0.566 0.930 0.483 0.343 4 0.787 0.439 0.282 0.292 0.564 0.328 0.254 0.749 0.320 0.523 5 0.538 0.399 0.257 0.368 0.457 0.716 0.211 0.432 0.427 0.193 6 0.625 0.439 0.414 0.340 0.859 0.836 0.381 0.366 0.389 0.686 7 0.343 0.699 0.828 0.305 0.358 0.732 0.427 0.343 0.312 0.320 8 0.356 0.396 0.737 0.445 0.378 0.335 0.505 0.765 0.638 0.696 9 0.792 0.470 0.277 0.533 0.218 0.409 0.668 0.828 0.429 0.892 10 0.513 0.622 0.683 0.457 0.320 0.328 0.353 0.310 0.584 0.546 11 0.180 0.353 0.787 0.536 0.307 0.218 0.417 0.277 0.409 0.292 12 0.645 0.566 0.559 0.406 0.437 0.622 0.790 0.300 0.686 0.335 13 0.536 0.267 0.432 0.551 0.264 0.320 0.414 0.391 0.216 0.434 14 0.201 0.274 0.523 0.325 0.272 0.391 0.267 0.516 0.323 0.450 15 0.262 0.460 0.318 0.295 0.305 0.257 0.282 0.292 0.325 0.259 16 0.635 0.904 0.432 0.620 0.508 0.556 0.810 0.432 0.399 0.528 17 0.389 0.437 0.777 1.064 0.699 0.315 0.561 1.003 0.775 0.704 18 0.765 0.554 0.866 0.526 0.612 0.323 0.544 0.391 0.358 0.447 19 0.312 0.429 0.419 0.584 0.391 0.284 0.401 0.508 0.749 1.092 20 0.386 0.521 0.320 0.401 0.457 0.445 0.508 0.384 0.472 0.584 21 1.019 0.643 0.384 0.493 0.566 0.371 0.643 0.820 0.686 0.318 22 0.328 0.356 0.333 0.282 0.333 0.279 0.333 0.287 0.432 0.414 23 0.765 0.399 0.417 0.559 0.597 0.577 0.414 0.452 0.566 0.338 24 0.551 0.536 0.838 0.622 0.737 0.368 0.445 0.635 1.064 0.356 25 0.142 0.645 1.062 0.749 0.866 0.302 0.409 0.714 0.907 0.483 26 0.361 0.216 0.671 0.267 0.287 0.643 0.445 0.305 0.673 0.312 27 0.381 0.315 0.508 0.528 0.516 0.290 0.305 0.693 0.475 0.503 28 0.305 0.254 0.323 0.521 0.343 0.325 0.394 0.257 0.330 0.526 29 0.411 0.724 1.262 0.513 0.409 0.211 0.483 0.864 0.310 0.409 30 0.218 0.262 0.396 0.536 0.940 0.269 0.401 0.498 0.292 0.500 31 0.127 0.368 0.538 0.211 0.284 0.638 0.493 0.249 0.175 0.287 32 0.599 0.592 0.927 0.681 0.683 0.597 0.531 0.706 0.800 1.105 33 0.300 0.394 0.627 1.240 1.130 0.343 0.361 0.419 0.894 0.785
87
Table A-3. Continued Oyster 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom 34 0.295 0.556 0.851 0.787 0.673 0.742 0.439 0.419 0.267 0.478 35 0.409 1.143 0.345 0.373 0.251 0.292 0.356 0.541 0.295 0.445 36 0.267 0.544 0.498 1.173 0.902 0.467 0.470 0.719 1.016 0.295 37 0.277 1.067 0.399 0.699 0.678 0.208 0.419 0.648 0.335 0.226 38 0.333 0.340 0.112 0.635 0.358 0.318 0.320 0.437 0.757 0.419 39 0.358 0.523 0.434 0.432 0.229 0.439 0.231 0.414 0.246 0.300 40 0.234 0.295 1.087 0.328 0.297 0.305 0.404 0.297 0.274 0.224 41 0.279 0.406 0.229 1.085 0.236 0.216 0.318 0.340 0.348 0.483 42 0.498 0.401 0.556 0.300 0.295 0.353 0.419 0.279 0.754 0.551 43 0.267 0.325 0.544 0.282 0.500 0.300 0.442 0.833 0.366 0.467 44 0.597 0.389 0.508 0.803 0.917 0.401 0.653 0.429 0.335 0.599 45 0.610 0.244 0.638 1.250 0.607 0.617 0.846 0.785 0.241 0.297 46 0.368 0.259 0.295 0.345 0.320 0.310 0.333 0.203 0.419 0.295 47 0.279 0.391 0.345 0.318 0.488 0.264 0.353 0.312 0.284 0.325 48 0.142 0.378 0.437 0.643 0.518 0.287 0.353 0.432 0.432 0.531 49 0.584 0.381 0.864 0.584 0.749 0.813 0.478 0.323 0.343 0.531 50 0.399 0.231 0.330 0.439 0.414 0.152 0.254 0.262 0.315 0.338 51 0.191 0.338 0.521 1.148 0.422 0.226 0.269 0.452 0.414 0.351 52 0.173 0.264 0.447 0.655 0.470 0.185 0.579 0.394 0.617 0.234 53 0.437 0.500 0.348 0.432 0.282 0.234 0.325 0.546 0.523 0.226 54 0.541 0.381 0.439 0.226 0.429 0.394 0.295 0.394 0.622 0.404 55 0.218 0.561 0.960 0.818 0.622 0.277 0.513 0.523 0.724 0.734 56 0.356 0.320 0.178 0.312 0.343 0.160 0.142 0.191 0.300 0.356 57 0.312 0.762 0.264 0.439 0.335 0.330 0.572 0.295 0.615 0.554 58 0.320 0.262 0.292 0.348 0.503 0.457 0.432 0.241 0.445 0.409 59 0.513 1.026 0.328 0.340 0.599 0.325 0.391 0.549 0.759 0.218 60 0.371 0.330 0.244 0.368 0.665 0.216 0.320 0.318 0.203 0.244 61 0.310 0.368 0.493 0.455 0.208 0.361 0.396 0.284 0.051 0.622 62 0.264 0.531 0.861 1.161 0.490 0.292 0.437 0.937 0.630 0.445 63 0.198 0.269 0.632 0.622 0.615 0.170 0.521 0.307 0.338 0.480 64 0.356 0.279 0.904 1.087 0.820 0.284 0.338 0.810 1.090 0.747 65 0.170 0.495 0.843 1.011 0.493 0.206 0.399 0.455 0.625 0.483 66 0.307 0.368 1.143 1.400 0.478 0.259 0.488 0.879 0.521 0.345 67 0.305 0.556 0.295 0.320 0.363 0.417 0.386 0.218 0.267 0.389 68 0.307 0.315 0.208 0.566 1.057 0.226 0.239 0.206 0.442 0.495 69 0.173 0.554 0.785 0.564 0.605 0.282 0.335 0.523 0.663 0.594 70 0.257 0.361 0.279 0.432 0.699 0.231 0.274 0.356 0.358 0.325 71 1.478 0.041 0.030 0.025 0.284 0.297 0.465 0.330 0.546 0.279 72 0.226 0.409 0.742 1.430 0.785 0.297 0.508 0.508 0.673 0.513 73 0.414 0.259 0.274 0.277 0.254 0.203 0.323 0.295 0.719 0.267 74 0.500 0.323 0.488 0.851 0.559 0.246 0.437 0.302 0.323 0.378 75 0.249 0.356 0.488 0.726 0.813 0.267 0.384 0.292 0.470 0.584 76 0.597 0.368 0.528 0.960 0.526 0.483 0.559 0.523 0.785 0.640 77 0.137 0.592 0.881 0.419 0.838 0.300 0.439 0.762 0.467 0.262 78 0.422 0.406 0.330 0.343 0.318 0.417 0.284 0.343 0.399 0.493 79 0.091 0.732 1.173 2.428 0.401 0.244 0.594 1.171 1.356 0.295 80 0.638 0.655 0.262 0.683 0.772 1.151 0.765 0.495 0.381 0.409 81 0.264 0.665 0.262 0.333 0.775 0.605 0.343 0.429 0.516 0.406 82 0.267 0.325 0.508 0.351 0.267 0.267 0.437 0.251 0.394 0.470 83 0.587 0.445 0.241 0.549 0.635 0.323 0.465 0.602 0.640 0.617 84 0.183 0.368 0.635 1.057 1.760 0.292 0.277 0.445 0.475 0.361
88
Table A-3. Continued Oyster 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom 85 0.241 0.404 0.305 0.597 0.345 0.160 0.511 0.330 0.290 0.203 86 0.279 0.292 0.465 0.401 0.406 0.429 0.269 0.432 0.523 0.533 87 0.315 0.610 0.485 0.417 0.378 0.292 0.389 0.292 0.358 0.333 88 0.376 0.612 1.026 0.394 0.625 0.333 0.462 1.039 1.095 0.434 89 0.257 0.432 0.528 0.417 0.373 0.622 0.274 0.384 0.409 0.371 90 0.544 0.536 0.546 0.815 0.521 0.729 0.450 0.457 0.678 0.556 91 0.467 0.396 0.828 0.546 0.269 0.226 0.533 0.574 0.716 0.533 92 0.381 0.356 0.353 0.330 0.211 0.310 0.229 0.305 0.229 0.269 93 0.391 0.445 0.767 0.310 0.546 0.338 0.284 0.262 0.556 0.432 94 0.282 0.216 0.422 0.556 0.427 0.290 0.538 0.290 0.351 0.312 95 0.206 0.282 0.381 0.541 0.274 0.292 0.424 0.274 0.226 0.338 96 0.549 0.582 0.701 0.711 0.366 0.279 0.681 0.361 0.688 0.549 97 0.279 0.193 0.678 0.518 0.264 0.221 0.284 0.579 0.396 0.216 98 0.323 0.231 0.541 0.283 0.726 0.472 0.351 0.320 0.432 0.279 99 0.419 0.429 0.406 0.409 0.640 0.330 0.518 0.462 0.338 0.318 100 0.417 0.465 0.795 0.333 0.371 0.345 0.485 0.683 0.333 0.259
Clam Measurements
Table A-4. Clam Weight Measurements in g (4/29/05) Clam Overall
wt Meat wt Shell
wt Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
1 36.6 8.5 28.1 14.0 14.1 3.31 0.99 1.65 1.66 2 33.5 10.6 22.9 11.4 11.5 2.16 0.99 1.08 1.08 3 40.6 10.6 30.0 15.0 15.0 2.83 1.00 1.42 1.42 4 37.8 9.8 28.0 14.1 13.9 2.86 1.01 1.44 1.42 5 38.4 11.8 26.6 13.3 13.3 2.25 1.00 1.13 1.13 6 33.5 10.3 23.2 11.4 11.8 2.25 0.97 1.11 1.15 7 37.8 11.5 26.3 13.3 13.0 2.29 1.02 1.16 1.13 8 39.5 13.7 25.8 13.0 12.8 1.88 1.02 0.95 0.93 9 47.2 14.3 32.9 16.3 16.6 2.30 0.98 1.14 1.16 10 44.3 15.5 28.8 14.5 14.3 1.86 1.01 0.94 0.92 11 42.8 14.4 28.4 14.3 14.1 1.97 1.01 0.99 0.98 12 46.0 13.9 32.1 16.0 16.1 2.31 0.99 1.15 1.16 13 40.4 13.9 26.5 13.3 13.2 1.91 1.01 0.96 0.95 14 38.7 12.0 26.7 13.4 13.3 2.23 1.01 1.12 1.11 15 30.3 8.6 21.7 11.0 10.7 2.52 1.03 1.28 1.24 16 41.2 13.3 27.9 14.0 13.9 2.10 1.01 1.05 1.05 17 39.7 11.8 27.9 14.0 13.9 2.36 1.01 1.19 1.18 18 40.4 15.1 25.3 12.7 12.6 1.68 1.01 0.84 0.83 19 43.1 12.4 30.7 15.3 15.4 2.48 0.99 1.23 1.24 20 38.4 10.9 27.5 13.9 13.6 2.52 1.02 1.28 1.25 21 49.1 15.1 34.0 17.3 16.7 2.25 1.04 1.15 1.11 22 60.1 18.6 41.5 20.6 20.9 2.23 0.99 1.11 1.12 23 36.3 11.4 24.9 12.4 12.5 2.18 0.99 1.09 1.10 24 35.6 12.5 23.1 11.6 11.5 1.85 1.01 0.93 0.92 25 39.1 11.3 27.8 14.0 13.8 2.46 1.01 1.24 1.22 26 44.9 16.2 28.7 143 14.3 1.77 10.00 8.83 0.88 27 46.0 15.3 30.7 15.4 15.3 2.01 1.01 1.01 1.00 28 35.7 9.6 26.1 13.0 13.1 2.72 0.99 1.35 1.36 29 37.2 10.1 27.1 13.5 13.6 2.68 0.99 1.34 1.35
89
Table A-4. Continued Clam Overall
wt Meat wt Shell
wt Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
30 36.5 10.3 26.2 13.0 13.2 2.54 0.98 1.26 1.28 31 36.9 11.6 25.3 12.6 12.7 2.18 0.99 1.09 1.09 32 38.9 12.1 26.8 13.5 13.3 2.21 1.02 1.12 1.10 33 35.0 12.8 22.2 11.2 11.0 1.73 1.02 0.88 0.86 34 42.7 13.8 28.9 14.4 14.5 2.09 0.99 1.04 1.05 35 48.3 16.9 31.4 15.5 15.9 1.86 0.97 0.92 0.94 36 42.8 13.9 28.9 14.3 14.6 2.08 0.98 1.03 1.05 37 36.2 11.8 24.4 12.0 12.4 2.07 0.97 1.02 1.05 38 50.0 15.2 34.8 17.2 17.6 2.29 0.98 1.13 1.16 39 37.1 8.8 28.3 14.2 14.1 3.22 1.01 1.61 1.60 40 39.1 12.6 26.5 13.4 13.1 2.10 1.02 1.06 1.04 41 45.5 13.5 32.0 16.0 16.0 2.37 1.00 1.19 1.19 42 37.3 13.8 23.5 12.0 11.5 1.70 1.04 0.87 0.83 43 48.3 12.0 36.3 18.0 18.3 3.03 0.98 1.50 1.53 44 39.5 12.4 27.1 13.7 13.4 2.19 1.02 1.10 1.08 45 40.2 13.8 26.4 13.0 13.4 1.91 0.97 0.94 0.97 46 34.1 10.5 23.6 11.6 12.0 2.25 0.97 1.10 1.14 47 32.5 11.9 20.6 10.3 10.3 1.73 1.00 0.87 0.87 48 42.9 11.7 31.2 15.4 15.8 2.67 0.97 1.32 1.35 49 33.6 10.6 23.0 11.4 11.6 2.17 0.98 1.08 1.09 50 49.3 16.0 33.3 16.5 16.8 2.08 0.98 1.03 1.05 51 36.0 11.9 24.1 12.0 12.1 2.03 0.99 1.01 1.02 52 37.2 12.3 24.9 12.3 12.6 2.02 0.98 1.00 1.02 53 35.8 11.7 24.1 12.0 12.1 2.06 0.99 1.03 1.03 54 45.7 15.4 30.3 15.2 15.1 1.97 1.01 0.99 0.98 55 44.2 12.9 31.3 15.5 15.8 2.43 0.98 1.20 1.22 56 40.4 12.5 27.9 14.0 13.9 2.23 1.01 1.12 1.11 57 33.9 8.4 25.5 12.8 12.7 3.04 1.01 1.52 1.51 58 37.9 11.0 26.9 13.5 13.4 2.45 1.01 1.23 1.22 59 38.5 10.8 27.7 13.9 13.8 2.56 1.01 1.29 1.28 60 26.9 7.1 19.8 10.0 9.8 2.79 1.02 1.41 1.38 61 38.0 10.4 27.6 13.8 13.8 2.65 1.00 1.33 1.33 62 47.7 14.9 32.8 16.5 16.3 2.20 1.01 1.11 1.09 63 36.2 10.6 25.6 13.0 12.6 2.42 1.03 1.23 1.19 64 34.9 9.4 25.5 12.8 12.7 2.71 1.01 1.36 1.35 65 40.0 11.3 28.7 14.4 14.3 2.54 1.01 1.27 1.27 66 42.5 13.3 29.2 14.7 14.5 2.20 1.01 1.11 1.09 67 35.6 9.9 25.7 12.9 12.8 2.60 1.01 1.30 1.29 68 32.7 11.0 21.7 10.9 10.8 1.97 1.01 0.99 0.98 69 46.2 13.0 33.2 16.7 16.5 2.55 1.01 1.28 1.27 70 47.2 17.0 30.2 15.3 14.9 1.78 1.03 0.90 0.88 71 52.6 16.1 36.5 18.1 18.4 2.27 0.98 1.12 1.14 72 38.6 12.6 26.0 13.3 12.7 2.06 1.05 1.06 1.01 73 41.5 11.9 29.6 15.1 14.5 2.49 1.04 1.27 1.22 74 43.3 13.3 30.0 15.0 15.0 2.26 1.00 1.13 1.13 75 46.0 13.4 32.6 16.2 16.4 2.43 0.99 1.21 1.22 76 42.1 13.2 28.9 14.3 14.6 2.19 0.98 1.08 1.11 77 39.9 14.3 25.6 13.0 12.6 1.79 1.03 0.91 0.88 78 36.0 9.5 26.5 13.3 13.2 2.79 1.01 1.40 1.39 79 41.5 13.4 28.1 14.2 13.9 2.10 1.02 1.06 1.04
90
Table A-4. Continued Clam Overall
wt Meat wt Shell
wt Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
80 39.8 13.3 26.5 13.4 13.1 1.99 1.02 1.01 0.98 81 51.1 14.7 36.4 18.3 18.1 2.48 1.01 1.24 1.23 82 42.8 14.4 28.4 14.4 14.0 1.97 1.03 1.00 0.97 83 44.2 16.1 28.1 14.2 13.9 1.75 1.02 0.88 0.86 84 43.8 13.4 30.4 15.4 15.0 2.27 1.03 1.15 1.12 85 37.9 12.3 25.6 13.0 12.6 2.08 1.03 1.06 1.02 86 47.4 13.9 33.5 17.0 16.5 2.41 1.03 1.22 1.19 87 48.0 16.9 31.1 15.3 15.8 1.84 0.97 0.91 0.93 88 42.6 13.8 28.8 14.2 14.6 2.09 0.97 1.03 1.06 89 51.1 16.8 34.3 17.0 17.3 2.04 0.98 1.01 1.03 90 36.8 13.9 22.9 11.6 11.3 1.65 1.03 0.83 0.81 91 34.1 12.4 21.7 10.9 10.8 1.75 1.01 0.88 0.87 92 32.5 10.8 21.7 10.9 10.8 2.01 1.01 1.01 1.00 93 45.8 14.8 31.0 15.6 15.4 2.09 1.01 1.05 1.04 94 55.1 18.9 36.2 18.0 18.2 1.92 0.99 0.95 0.96 95 35.8 10.5 25.3 12.7 12.6 2.41 1.01 1.21 1.20 96 41.3 12.0 29.3 14.8 14.5 2.44 1.02 1.23 1.21 97 38.8 12.1 26.7 13.1 13.6 2.21 0.96 1.08 1.12 98 39.5 14.2 25.3 12.8 12.5 1.78 1.02 0.90 0.88 99 35.9 9.5 26.4 13.2 13.2 2.78 1.00 1.39 1.39 100 35.4 11.9 23.5 11.8 11.7 1.97 1.01 0.99 0.98
Table A-5. Clam Dimension Measurement in cm (5/10/05) Clam
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
1 4.45 1.45 4.95 4.5 1.4 4.95 4.5 2.85 4.95 2 4.4 1.45 5.0 4.35 1.35 5.0 4.4 2.8 5.0 3 4.6 1.45 5.1 4.55 1.5 5.1 4.6 2.95 5.1 4 4.3 1.5 5.2 4.45 1.45 5.25 4.45 2.95 5.25 5 4.2 1.45 4.9 4.2 1.4 4.8 4.2 2.85 4.9 6 4.0 1.45 4.6 4.15 1.45 4.55 4.15 2.9 4.6 7 4.15 1.35 4.9 4.2 1.45 4.9 4.2 2.8 4.9 8 4.35 1.4 4.85 4.4 1.45 4.85 4.4 2.85 4.85 9 4.4 1.5 5.4 4.5 1.5 5.4 4.5 3.0 5.4 10 4.3 1.45 5.2 4.55 1.45 5.2 4.55 2.9 5.2 11 4.5 1.5 4.95 4.4 1.4 5.0 4.5 2.9 5.0 12 4.4 1.45 5.25 4.3 1.35 5.15 4.4 2.8 5.25 13 4.3 1.45 5.05 4.2 1.5 5.1 4.3 2.95 5.1 14 4.3 1.45 4.8 4.35 1.45 4.85 4.35 2.9 4.85 15 3.8 1.5 4.45 3.8 1.35 4.5 3.8 2.85 4.5 16 4.3 1.35 4.8 4.35 1.4 4.75 4.35 2.75 4.8 17 4.1 1.5 4.9 4.3 1.55 4.9 4.3 3.05 4.9 18 4.0 1.4 4.6 4.0 1.4 4.7 4.0 2.8 4.7 19 4.8 1.4 5.45 4.8 1.3 5.4 4.8 2.7 5.45 20 4.4 1.45 5.1 4.3 1.45 5.05 4.4 2.9 5.1 21 4.75 1.45 5.5 4.75 1.4 5.5 4.75 2.85 5.5 22 4.7 1.5 5.9 4.85 1.6 5.9 4.85 3.1 5.9 23 4.1 1.4 4.9 4.1 1.45 4.85 4.1 2.85 4.9 24 4.4 1.4 4.9 4.3 1.4 4.85 4.4 2.8 4.9 25 4.45 1.4 4.85 4.4 1.45 4.8 4.45 2.85 4.85
91
Table A-5. Continued Clam
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
26 4.1 1.4 5.15 4.2 1.4 5.1 4.2 2.8 5.15 27 4.35 1.4 5.3 4.3 1.45 5.25 4.35 2.85 5.3 28 4.0 1.4 4.85 4.0 1.35 4.85 4.0 2.75 4.85 29 4.25 1.45 4.7 4.25 1.4 4.7 4.25 2.85 4.7 30 4.15 1.5 4.95 4.35 1.55 5.0 4.35 3.05 5.0 31 4.1 1.45 4.9 4.1 1.3 4.8 4.1 2.75 4.9 32 4.35 1.4 5.05 4.3 1.4 5.05 4.35 2.8 5.05 33 3.95 1.3 4.5 4.0 1.35 4.5 4.0 2.65 4.5 34 4.35 1.3 4.95 4.35 1.5 4.95 4.35 2.8 4.95 35 4.7 1.5 5.2 4.55 1.6 5.2 4.7 3.1 5.2 36 4.55 1.45 5.2 4.6 1.35 5.2 4.6 2.8 5.2 37 4.05 1.4 4.9 4.2 1.4 4.9 4.2 2.8 4.9 38 4.6 1.4 5.4 4.4 1.5 5.25 4.6 2.9 5.4 39 4.15 1.55 4.8 4.25 1.5 4.8 4.25 3.05 4.8 40 4.35 1.4 4.8 4.3 1.4 4.8 4.35 2.8 4.8 41 4.4 1.5 5.1 4.45 1.4 5.2 4.45 2.9 5.2 42 4.5 1.4 5.0 4.4 1.4 4.95 4.5 2.8 5.0 43 4.6 1.45 5.4 4.8 1.4 4.45 4.8 2.85 5.4 44 4.2 1.4 4.8 4.25 1.45 4.8 4.25 2.85 4.8 45 4.15 1.35 4.8 4.3 1.4 4.85 4.3 2.75 4.85 46 4.05 1.45 4.8 4.2 1.3 4.75 4.2 2.75 4.8 47 4.0 1.2 4.4 4.05 1.45 4.45 4.05 2.65 4.45 48 4.35 1.55 5.0 4.35 1.5 5.05 4.35 3.05 5.05 49 4.0 1.4 4.7 4.1 1.2 4.7 4.1 2.6 4.7 50 4.4 1.4 5.4 4.5 1.55 5.35 4.5 2.95 5.4 51 4.0 1.5 4.4 3.95 1.45 4.5 4.0 2.95 4.5 52 4.05 1.4 5.0 4.05 1.4 4.9 4.05 2.8 5.0 53 3.95 1.35 4.9 4.05 1.3 4.9 4.05 2.65 4.9 54 4.35 1.45 5.15 4.55 1.45 5.2 4.55 2.9 5.2 55 4.3 1.55 5.3 4.45 1.5 5.25 4.45 3.05 5.3 56 4.25 1.4 5.05 4.2 1.35 5.05 4.25 2.75 5.05 57 4.3 1.45 4.95 4.1 1.4 4.95 4.3 2.85 4.95 58 4.25 1.4 4.85 4.3 1.4 4.9 4.3 2.8 4.9 59 4.2 1.5 4.75 4.2 1.4 4.75 4.2 2.9 4.75 60 4.0 1.25 4.3 3.95 1.4 4.35 4.0 2.65 4.35 61 4.3 1.4 4.9 4.25 1.55 4.9 4.3 2.95 4.9 62 4.6 1.6 5.1 4.65 1.65 5.15 4.65 3.25 5.15 63 4.1 1.35 4.7 4.2 1.4 4.7 4.2 2.75 4.7 64 4.20 1.4 4.95 4.25 1.3 4.55 4.25 2.7 4.95 65 4.45 1.4 4.9 4.4 1.4 4.9 4.45 2.8 4.9 66 4.3 1.6 4.85 4.4 1.5 5.0 4.4 3.1 5.0 67 4.45 1.4 4.9 4.45 1.45 4.9 4.45 2.85 4.9 68 4.0 1.35 4.5 4.0 1.35 4.5 4.0 2.7 4.5 69 4.5 1.5 5.0 4.55 1.5 5.0 4.55 3.0 5.0 70 4.1 1.4 4.8 4.15 1.45 4.8 4.15 2.85 4.8 71 4.6 1.5 5.25 4.6 1.5 5.3 4.6 3.0 5.3 72 4.6 1.4 5.5 4.6 1.3 5.5 4.6 2.7 5.5 73 4.35 1.3 4.9 4.2 1.35 4.9 4.35 2.65 4.9 74 4.45 1.4 5.0 4.4 1.4 5.0 4.45 2.8 5.0 75 4.3 1.45 5.0 4.35 1.4 5.0 4.35 2.85 5.0
92
Table A-5. Continued Clam
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
76 4.35 1.3 4.8 4.4 1.25 4.9 4.4 2.55 4.9 77 4.05 1.35 4.85 4.1 1.35 4.85 4.1 2.7 4.85 78 4.0 1.4 4.55 4.05 1.4 4.5 4.05 2.8 4.55 79 4.05 1.3 4.9 4.1 1.35 4.95 4.1 2.65 4.95 80 4.2 1.4 5.0 4.3 1.45 4.95 4.3 2.85 5.0 81 4.5 1.5 5.3 4.9 1.4 5.2 4.9 2.9 5.3 82 4.45 1.35 5.0 4.5 1.45 5.0 4.5 2.8 5.0 83 4.4 1.5 5.0 4.4 1.4 5.05 4.4 2.9 5.05 84 4.15 1.45 4.7 4.2 1.45 4.7 4.2 2.9 4.7 85 4.3 1.5 4.95 4.3 1.4 4.95 4.3 2.9 4.95 86 4.75 1.4 5.4 4.7 1.45 5.4 4.75 2.85 5.4 87 4.4 1.45 5.3 4.5 1.45 5.35 4.5 2.9 5.35 88 4.2 1.35 4.9 4.3 1.35 4.9 4.3 2.7 4.9 89 4.65 1.45 5.4 4.7 1.45 5.4 4.7 2.9 5.4 90 4.15 1.35 4.6 4.03 1.4 4.6 4.15 2.75 4.6 91 4.0 1.2 4.3 4.0 1.45 4.5 4.0 2.65 4.5 92 4.0 1.4 4.65 4.0 1.4 4.65 4.0 2.8 4.65 93 4.7 1.2 5.25 4.55 1.5 5.2 4.7 2.7 4.25 94 4.7 1.45 5.4 4.6 1.5 5.25 4.7 2.95 5.4 95 4.0 1.3 4.55 4.0 1.35 4.5 4.0 2.65 4.55 96 4.2 1.5 4.75 4.2 1.55 4.75 4.2 3.05 4.75 97 4.2 1.35 4.95 4.2 1.4 4.85 4.2 2.75 4.95 98 4.1 1.4 4.8 4.2 1.3 4.8 4.2 2.7 4.8 99 4.3 1.4 4.8 4.75 1.45 4.8 4.75 2.85 4.8 100 4.15 1.4 4.45 4.0 1.3 4.5 4.15 2.7 4.5 Table A-6. Clam Thickness Measurement in cm (5/12/05) Clam 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom
1 0.29 0.33 0.32 0.33 0.34 0.28 0.37 0.34 0.35 0.30 2 0.24 0.28 0.26 0.32 0.34 0.26 0.32 0.31 0.31 0.31 3 0.30 0.29 0.33 0.30 0.34 0.29 0.33 0.32 0.33 0.33 4 0.28 0.30 0.28 0.37 0.36 0.29 0.31 0.30 0.36 0.35 5 0.28 0.27 0.28 0.26 0.27 0.27 0.27 0.25 0.27 0.26 6 0.27 0.31 0.29 0.32 0.34 0.27 0.31 0.30 0.32 0.31 7 0.27 0.32 0.33 0.31 0.31 0.28 0.31 0.32 0.31 0.34 8 0.26 0.30 0.30 0.34 0.34 0.27 0.32 0.30 0.31 0.32 9 0.31 0.31 0.33 0.35 0.34 0.30 0.37 0.34 0.33 0.33 10 0.27 0.31 0.27 0.31 0.32 0.26 0.35 0.32 0.31 0.33 11 0.27 0.30 0.29 0.34 0.30 0.27 0.33 0.31 0.33 0.33 12 0.30 0.30 0.32 0.36 0.37 0.28 0.35 0.31 0.38 0.38 13 0.29 0.27 0.29 0.27 0.28 0.27 0.28 0.27 0.34 0.34 14 0.28 0.28 0.31 0.30 0.30 0.31 0.29 0.31 0.35 0.35 15 0.26 0.30 0.29 0.33 0.33 0.26 0.31 0.31 0.33 0.32 16 0.29 0.29 0.35 0.36 0.32 0.30 0.38 0.33 0.32 0.37 17 0.27 0.29 0.31 0.36 0.34 0.27 0.32 0.31 0.35 0.36 18 0.28 0.29 0.35 0.32 0.33 0.26 0.34 0.36 0.35 0.35 19 0.24 0.26 0.27 0.28 0.28 0.26 0.26 0.31 0.30 0.29 20 0.26 0.27 0.32 0.29 0.28 0.26 0.36 0.32 0.28 0.27 21 0.27 0.30 0.30 0.28 0.28 0.27 0.29 0.31 0.27 0.27 22 0.29 0.32 0.33 0.30 0.32 0.28 0.30 0.31 0.31 0.32
93
Table A-6. Continued Clam 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom
23 0.27 0.27 0.31 0.30 0.30 0.27 0.32 0.31 0.31 0.30 24 0.26 0.30 0.31 0.28 0.29 0.27 0.31 0.27 0.32 0.30 25 0.26 0.30 0.30 0.32 0.32 0.26 0.28 0.29 0.31 0.31 26 0.28 0.27 0.31 0.30 0.30 0.28 0.32 0.30 0.30 0.33 27 0.28 0.27 0.32 0.28 0.29 0.31 0.37 0.34 0.36 0.35 28 0.26 0.32 0.27 0.29 0.28 0.25 0.31 0.26 0.29 0.29 29 0.26 0.30 0.28 0.32 0.29 0.28 0.26 0.29 0.29 0.28 30 0.28 0.28 0.30 0.30 0.30 0.28 0.29 0.29 0.33 0.33 31 0.28 0.27 0.31 0.26 0.25 0.28 0.27 0.30 0.25 0.25 32 0.27 0.28 0.30 0.27 0.27 0.25 0.28 0.31 0.27 0.26 33 0.25 0.28 0.27 0.28 0.27 0.25 0.28 0.27 0.27 0.27 34 0.25 0.28 0.31 0.26 0.26 0.25 0.27 0.31 0.26 0.26 35 0.29 0.29 0.33 0.37 0.37 0.27 0.31 0.31 0.33 0.37 36 0.27 0.26 0.30 0.25 0.27 0.26 0.27 0.31 0.27 0.26 37 0.26 0.30 0.28 0.27 0.27 0.26 0.28 0.31 0.26 0.26 38 0.27 0.29 0.31 0.29 0.31 0.31 0.25 0.30 0.30 0.31 39 0.28 0.30 0.32 0.33 0.34 0.28 0.36 0.34 0.34 0.34 40 0.26 0.32 0.34 0.30 0.30 0.28 0.32 0.32 0.29 0.28 41 0.27 0.28 0.31 0.28 0.28 0.27 0.28 0.32 0.27 0.27 42 0.27 0.29 0.32 0.26 0.26 0.29 0.27 0.27 0.27 0.00 43 0.27 0.28 0.31 0.28 0.28 0.26 0.28 0.32 0.27 0.27 44 0.28 0.26 0.31 0.28 0.28 0.27 0.26 0.30 0.27 0.28 45 0.27 0.28 0.31 0.29 0.29 0.30 0.31 0.30 0.28 0.30 46 0.27 0.26 0.30 0.25 0.27 0.26 0.25 0.30 0.29 0.30 47 0.26 0.29 0.31 0.26 0.26 0.26 0.29 0.31 0.26 0.26 48 0.27 0.29 0.32 0.32 0.32 0.28 0.28 0.31 0.30 0.30 49 0.26 0.30 0.31 0.30 0.30 0.26 0.31 0.30 0.28 0.31 50 0.28 0.34 0.32 0.28 0.28 0.28 0.33 0.31 0.29 0.29 51 0.26 0.26 0.33 0.25 0.26 0.28 0.26 0.32 0.26 0.26 52 0.27 0.26 0.30 0.27 0.27 0.26 0.26 0.31 0.27 0.27 53 0.26 0.32 0.27 0.29 0.28 0.25 0.31 0.26 0.29 0.29 54 0.27 0.26 0.30 0.28 0.28 0.27 0.26 0.30 0.28 0.28 55 0.28 0.27 0.29 0.27 0.28 0.26 0.31 0.31 0.26 0.27 56 0.26 0.30 0.29 0.30 0.30 0.27 0.28 0.29 0.27 0.28 57 0.27 0.28 0.31 0.28 0.29 0.26 0.27 0.31 0.28 0.28 58 0.28 0.32 0.31 0.30 0.30 0.28 0.28 0.31 0.31 0.30 59 0.26 0.27 0.32 0.26 0.26 0.26 0.27 0.31 0.28 0.28 60 0.25 0.31 0.27 0.31 0.30 0.26 0.30 0.27 0.27 0.26 61 0.28 0.27 0.31 0.26 0.26 0.28 0.26 0.32 0.26 0.26 62 0.27 0.30 0.30 0.30 0.30 0.26 0.31 0.29 0.30 0.30 63 0.25 0.28 0.33 0.31 0.30 0.26 0.28 0.32 0.29 0.29 64 0.27 0.29 0.30 0.28 0.28 0.26 0.30 0.31 0.27 0.27 65 0.26 0.28 0.30 0.33 0.33 0.26 0.27 0.27 0.34 0.35 66 0.32 0.29 0.27 0.26 0.26 0.29 0.27 0.27 0.27 0.27 67 0.27 0.28 0.30 0.27 0.27 0.25 0.28 0.31 0.27 0.26 68 0.25 0.26 0.28 0.27 0.27 0.24 0.27 0.30 0.26 0.27 69 0.26 0.32 0.35 0.32 0.31 0.25 0.31 0.34 0.31 0.31 70 0.29 0.25 0.29 0.31 0.31 0.28 0.26 0.31 0.30 0.30 71 0.26 0.27 0.27 0.31 0.32 0.25 0.27 0.28 0.30 0.31 72 0.30 0.31 0.32 0.32 0.32 0.26 0.30 0.32 0.31 0.31
94
Table A-6. Continued Clam 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom
73 0.31 0.30 0.34 0.32 0.32 0.31 0.31 0.33 0.37 0.36 74 0.30 0.27 0.32 0.27 0.27 0.29 0.27 0.32 0.30 0.31 75 0.26 0.31 0.29 0.30 0.30 0.25 0.30 0.28 0.30 0.30 76 0.27 0.28 0.33 0.30 0.29 0.27 0.28 0.32 0.29 0.29 77 0.26 0.30 0.28 0.35 0.34 0.26 0.30 0.27 0.32 0.32 78 0.25 0.31 0.33 0.30 0.29 0.26 0.30 0.31 0.28 0.30 79 0.25 0.28 0.27 0.28 0.27 0.25 0.28 0.27 0.27 0.27 80 0.26 0.29 0.30 0.30 0.30 0.25 0.28 0.29 0.29 0.30 81 0.29 0.32 0.34 0.30 0.30 0.28 0.32 0.32 0.29 0.28 82 0.28 0.27 0.30 0.29 0.29 0.27 0.27 0.28 0.29 0.29 83 0.28 0.33 0.32 0.36 0.34 0.27 0.33 0.32 0.32 0.32 84 0.28 0.29 0.33 0.30 0.30 0.27 0.29 0.31 0.30 0.30 85 0.27 0.28 0.26 0.28 0.28 0.26 0.27 0.27 0.28 0.28 86 0.28 0.27 0.31 0.31 0.31 0.28 0.27 0.29 0.31 0.31 87 0.23 0.28 0.29 0.28 0.29 0.26 0.27 0.31 0.28 0.28 88 0.30 0.35 0.33 0.31 0.32 0.30 0.36 0.33 0.32 0.31 89 0.27 0.28 0.31 0.28 0.28 0.27 0.28 0.32 0.27 0.27 90 0.26 0.26 0.27 0.31 0.31 0.26 0.30 0.27 0.28 0.32 91 0.25 0.29 0.32 0.31 0.31 0.26 0.28 0.31 0.31 0.31 92 0.25 0.25 0.28 0.26 0.26 0.25 0.26 0.28 0.26 0.26 93 0.27 0.32 0.32 0.32 0.32 0.27 0.32 0.28 0.31 0.33 94 0.27 0.28 0.31 0.28 0.28 0.26 0.28 0.32 0.27 0.27 95 0.29 0.32 0.31 0.32 0.32 0.28 0.33 0.35 0.34 0.32 96 0.30 0.32 0.32 0.35 0.35 0.29 0.31 0.31 0.35 0.32 97 0.28 0.30 0.30 0.28 0.28 0.27 0.27 0.30 0.27 0.27 98 0.28 0.33 0.28 0.32 0.32 0.28 0.32 0.31 0.32 0.32 99 0.28 0.33 0.30 0.31 0.34 0.28 0.29 0.30 0.31 0.31 100 0.25 0.26 0.28 0.27 0.27 0.26 0.30 0.26 0.29 0.30
Mussel Measurement
Table A-7. Mussel Weight Measurement in g (5/12/05) Mussel Overall
Wt Meat Wt
Shell Wt
Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
1 22.9 13.4 9.5 5.0 4.5 0.71 1.11 0.37 0.34 2 19.6 10.7 8.9 4.45 4.45 0.83 1.00 0.42 0.42 3 17 9.2 7.8 3.8 4 0.85 0.95 0.41 0.43 4 10.7 6.6 4.1 2.05 2.05 0.62 1.00 0.31 0.31 5 18.6 12.1 6.5 3.3 3.2 0.54 1.03 0.27 0.26 6 14.2 6.4 7.8 3.7 4.1 1.22 0.90 0.58 0.64 7 10.9 5.0 5.9 3.1 2.8 1.18 1.11 0.62 0.56 8 14.4 8.2 6.2 3.3 2.9 0.76 1.14 0.40 0.35 9 11.7 6.8 4.9 2.5 2.4 0.72 1.04 0.37 0.35 10 15.9 10.0 5.9 3.1 2.8 0.59 1.11 0.31 0.28 11 14.3 7.0 7.3 3.65 3.65 1.04 1.00 0.52 0.52 12 15.3 8.2 7.1 3.4 3.7 0.87 0.92 0.41 0.45 13 23.8 14.5 9.3 4.4 4.9 0.64 0.90 0.30 0.34 14 18.8 10.9 7.9 3.8 4.1 0.72 0.93 0.35 0.38 15 17.2 10.4 6.8 3.6 3.2 0.65 1.13 0.35 0.31 16 15.6 9.1 6.5 3.25 3.25 0.71 1.00 0.36 0.36
95
Table A-7. Continued Mussel Overall
Wt Meat Wt
Shell Wt
Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
17 14.3 7.3 7.0 3.0 4 0.96 0.75 0.41 0.55 18 22.1 13.1 9.0 4.2 4.8 0.69 0.88 0.32 0.37 19 12.8 6.6 6.2 3 3.2 0.94 0.94 0.45 0.48 20 15.7 9.7 6.0 3.2 2.8 0.62 1.14 0.33 0.29 21 17.6 11.2 6.4 3.2 3.2 0.57 1.00 0.29 0.29 22 10.3 5.4 4.9 2.6 2.3 0.91 1.13 0.48 0.43 23 18.2 10.3 7.9 3.80 4.1 0.77 0.93 0.37 0.40 24 13.9 8.4 5.5 2.75 2.75 0.65 1.00 0.33 0.33 25 16.8 9.5 7.3 3.8 3.5 0.77 1.09 0.40 0.37 26 8.3 4.0 4.3 2.3 2 1.08 1.15 0.58 0.50 27 27.6 14.6 13.0 6.8 6.2 0.89 1.10 0.47 0.42 28 21.1 11.9 9.2 4.6 4.6 0.77 1.00 0.39 0.39 29 10.1 5.2 4.9 2.6 2.3 0.94 1.13 0.50 0.44 30 15.4 6.6 8.8 4.4 4.4 1.33 1.00 0.67 0.67 31 18.9 11.2 7.7 4.0 3.7 0.69 1.08 0.36 0.33 32 15.4 8.6 6.8 3.6 3.2 0.79 1.13 0.42 0.37 33 15.7 8.0 7.7 4.0 3.7 0.96 1.08 0.50 0.46 34 18.4 7.2 11.2 5.6 5.6 1.56 1.00 0.78 0.78 35 22.7 10.3 12.4 6.0 6.4 1.20 0.94 0.58 0.62 36 12.2 6.1 6.1 3.2 2.9 1.00 1.10 0.52 0.48 37 16.3 8.1 8.2 4.3 3.9 1.01 1.10 0.53 0.48 38 9.1 4.7 4.4 2.5 1.9 0.94 1.32 0.53 0.40 39 10.5 4.8 5.7 2.9 2.8 1.19 1.04 0.60 0.58 40 13.5 6.6 6.9 3.1 3.8 1.05 0.82 0.47 0.58 41 10.8 5.6 5.2 3.0 2.2 0.93 1.36 0.54 0.39 42 13.2 6.0 7.2 3.7 3.5 1.20 1.06 0.62 0.58 43 13.1 6.8 6.3 3.4 2.9 0.93 1.17 0.50 0.43 44 10.4 3.7 6.7 3.5 3.2 1.81 1.09 0.95 0.86 45 13.4 6.7 6.7 3.2 3.5 1.00 0.91 0.48 0.52 46 11.3 4.7 6.6 3.1 3.5 1.40 0.89 0.66 0.74 47 7.6 3.1 4.5 2.2 2.3 1.45 0.96 0.71 0.74 48 8.5 3.0 5.5 2.75 2.75 1.83 1.00 0.92 0.92 49 10.9 4.6 6.3 3.0 3.3 1.37 0.91 0.65 0.72 50 9.2 3.7 5.5 2.9 2.6 1.49 1.12 0.78 0.70 51 12.2 5.9 6.3 3.0 3.3 1.07 0.91 0.51 0.56 52 14.8 8.1 6.7 3.3 3.4 0.83 0.97 0.41 0.42 53 11.6 5.6 6.0 3.1 2.9 1.07 1.07 0.55 0.52 54 12.8 5.8 7.0 3.1 3.9 1.21 0.79 0.53 0.67 55 11.2 6.0 5.2 2.9 2.3 0.87 1.26 0.48 0.38 56 9.3 3.9 5.4 3.0 2.4 1.38 1.25 0.77 0.62 57 16.7 7.9 8.8 4.1 4.7 1.11 0.87 0.52 0.59 58 8.8 3.9 4.9 2.3 2.6 1.26 0.88 0.59 0.67 59 8.3 3.0 5.3 2.65 2.65 1.77 1.00 0.88 0.88 60 9.5 4.5 5.0 2.5 2.5 1.11 1.00 0.56 0.56 61 10.1 5.3 4.8 2.7 2.1 0.91 1.29 0.51 0.40 62 7.6 2.8 4.8 2.0 2.8 1.71 0.71 0.71 1.00 63 9.9 4.4 5.5 2.75 2.75 1.25 1.00 0.63 0.63 64 9.3 4.2 5.1 2.4 2.7 1.21 0.89 0.57 0.64 65 10.4 4.3 6.1 2.9 3.2 1.42 0.91 0.67 0.74 66 11.1 5.3 5.8 3.1 2.7 1.09 1.15 0.58 0.51
96
Table A-7. Continued Mussel Overall
Wt Meat Wt
Shell Wt
Top Shell wt
Bottom Shell wt
Shell/ Meat
Top/ Bottom
Top/ Meat
Bottom/ Meat
68 11.3 4.0 7.3 3.6 3.7 1.83 0.97 0.90 0.93 69 8.7 3.5 5.2 2.4 2.8 1.49 0.86 0.69 0.80 70 11.7 4.9 6.8 3.6 3.2 1.39 1.13 0.73 0.65 71 10.8 3.9 6.9 3.3 3.6 1.77 0.92 0.85 0.92 72 8.8 4.2 4.6 2.3 2.3 1.10 1.00 0.55 0.55 73 8.5 3.7 4.8 2.4 2.4 1.30 1.00 0.65 0.65 74 8.2 3.4 4.8 2.5 2.3 1.41 1.09 0.74 0.68 75 11.1 4.6 6.5 3.3 3.2 1.41 1.03 0.72 0.70 76 7.7 3.4 4.3 2.3 2 1.26 1.15 0.68 0.59 77 18.6 9.8 8.8 4.1 4.7 0.90 0.87 0.42 0.48 78 10.4 4.4 6.0 3.2 2.8 1.36 1.14 0.73 0.64 79 9.1 3.0 6.1 3.0 3.1 2.03 0.97 1.00 1.03 80 14.3 8.1 6.2 2.8 3.4 0.77 0.82 0.35 0.42 81 11.4 5.0 6.4 3.2 3.2 1.28 1.00 0.64 0.64 82 9.1 4.3 4.8 2.4 2.4 1.12 1.00 0.56 0.56 83 6.3 2.0 4.3 2.15 2.15 2.15 1.00 1.08 1.08 84 6.7 2.6 4.1 2.2 1.9 1.58 1.16 0.85 0.73 85 7 2.3 4.7 2.2 2.5 2.04 0.88 0.96 1.09 86 8.4 3.5 4.9 2.3 2.6 1.40 0.88 0.66 0.74 87 9.2 3.6 5.6 2.6 3 1.56 0.87 0.72 0.83 88 10.5 4.7 5.8 2.7 3.1 1.23 0.87 0.57 0.66 89 12.3 5.5 6.8 3.1 3.7 1.24 0.84 0.56 0.67 90 10.4 4.1 6.3 3.25 3.05 1.54 1.07 0.79 0.74 91 9.6 4.9 4.7 2.1 2.6 0.96 0.81 0.43 0.53 92 6.3 1.9 4.4 2.0 2.4 2.32 0.83 1.05 1.26 93 13.9 5.4 8.5 4.1 4.4 1.57 0.93 0.76 0.81 94 8.2 2.5 5.7 2.9 2.8 2.28 1.04 1.16 1.12 95 11.6 4.0 7.6 4.0 3.6 1.90 1.11 1.00 0.90 96 12.3 4.0 8.3 4.3 4 2.08 1.08 1.08 1.00 97 8.9 3.8 5.1 2.60 2.5 1.34 1.04 0.68 0.66 98 10.9 4.3 6.6 3.3 3.3 1.53 1.00 0.77 0.77 99 8.8 3.8 5.0 2.8 2.2 1.32 1.27 0.74 0.58 100 12.8 6.7 6.1 3.2 2.9 0.91 1.10 0.48 0.43
Table A-8. Mussel Dimension Measurement in cm (5/20/05) Mussel
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
1 6.10 2.40 2.80 6.05 2.45 2.85 6.10 4.85 2.85 2 5.50 1.15 2.75 5.50 1.15 2.70 5.50 2.30 2.75 3 6.20 1.10 2.50 6.15 1.05 2.45 6.20 2.15 2.50 4 5.95 1.20 3.45 6.00 1.00 3.45 6.00 2.20 3.45 5 4.90 1.35 3.95 4.90 1.25 3.90 4.90 2.60 3.95 6 6.70 0.95 2.95 6.80 0.95 2.90 6.80 1.90 2.95 7 5.30 1.20 3.50 5.35 1.20 3.50 5.35 2.40 3.50 8 5.25 1.00 3.75 5.25 1.00 3.80 5.25 2.00 3.80 9 5.25 1.15 3.25 5.25 1.20 3.30 5.25 2.35 3.30 10 6.05 1.10 3.15 6.15 1.15 3.15 6.15 2.25 3.15 11 6.30 1.35 2.95 6.35 1.35 2.95 6.35 2.70 2.95 12 5.50 1.45 3.65 5.50 1.45 3.65 5.50 2.90 3.65 13 4.95 1.00 3.00 5.00 1.00 3.05 5.00 2.00 3.05
97
Table A-8 Continued Mussel
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
14 6.40 1.30 3.35 6.40 1.35 3.30 6.40 2.65 3.35 15 5.80 1.05 3.00 5.80 1.10 3.00 5.80 2.15 3.00 16 6.00 1.20 2.80 6.00 1.25 2.85 6.00 2.45 2.85 17 4.50 1.35 3.40 4.55 1.35 3.40 4.55 2.70 3.40 18 5.85 1.75 3.65 5.85 1.75 3.65 5.85 3.50 3.65 19 5.00 1.45 2.95 5.05 1.50 2.95 5.05 2.95 2.95 20 5.30 1.00 3.00 5.30 0.95 3.00 5.30 1.95 3.00 21 5.45 1.10 2.80 5.50 1.15 2.80 5.50 2.25 2.80 22 5.30 1.00 2.90 5.30 1.00 2.95 5.30 2.00 2.95 23 6.15 1.15 2.60 6.15 1.05 2.60 6.15 2.20 2.60 24 5.80 1.20 3.35 5.85 1.20 3.50 5.85 2.40 3.35 25 6.00 1.10 3.40 6.00 1.10 3.40 6.00 2.20 3.40 26 5.30 1.00 3.00 5.30 0.95 3.10 5.30 1.95 3.10 27 5.95 1.25 3.40 5.90 1.30 3.25 5.95 2.55 3.40 28 5.50 1.20 3.50 5.50 1.20 3.55 5.50 2.40 3.55 29 5.50 1.00 2.90 5.50 0.95 2.90 5.50 1.95 2.90 30 5.95 1.20 3.50 6.00 1.00 3.45 6.00 2.20 3.50 31 6.30 1.35 2.95 6.35 1.35 2.95 6.35 2.70 2.95 32 5.95 0.95 2.95 5.95 1.00 2.90 5.95 1.95 2.95 33 6.15 1.00 3.25 6.10 1.00 3.20 6.15 2.00 3.25 34 4.75 1.10 3.10 4.80 1.10 3.10 4.80 2.20 3.10 35 6.15 1.15 2.60 6.15 1.05 2.65 6.15 2.20 2.65 36 5.30 1.25 3.35 5.25 1.20 3.35 5.30 2.45 3.35 37 4.95 1.00 3.00 5.00 1.00 3.05 5.00 2.00 3.05 38 5.00 1.45 3.10 5.05 1.50 2.95 5.05 2.95 3.10 39 6.70 0.95 2.95 6.80 0.95 2.90 6.80 1.90 2.95 40 4.95 1.05 3.25 5.00 1.10 3.25 5.00 2.15 3.10 41 5.05 1.05 2.95 4.70 1.05 2.90 5.05 2.10 2.95 42 5.05 1.10 3.10 5.05 1.10 3.10 5.05 2.20 3.10 43 6.15 1.15 2.60 6.15 1.05 2.60 6.15 2.20 2.60 44 4.95 1.00 3.00 5.00 1.00 3.05 5.00 2.00 3.05 45 6.15 1.00 3.25 6.10 1.00 3.20 6.15 2.00 3.25 46 5.25 1.15 3.25 5.25 1.20 3.30 5.25 2.35 3.30 47 5.10 1.15 3.05 5.15 1.20 3.00 5.15 2.35 3.05 48 5.95 1.25 2.95 5.95 1.25 3.00 5.95 2.50 3.00 49 5.60 1.10 3.30 5.60 1.10 3.30 5.60 2.20 3.30 50 6.70 1.20 3.40 6.70 1.20 3.40 6.70 2.40 3.40 51 4.95 1.35 3.05 5.00 1.40 3.00 5.00 2.75 3.00 52 5.30 1.25 3.25 5.25 1.20 3.25 5.30 2.45 3.25 53 5.95 1.00 2.95 6.00 1.05 3.00 6.00 2.05 3.00 54 5.90 1.30 3.15 5.90 1.30 3.20 5.90 2.60 3.20 55 5.80 1.00 3.45 5.70 1.05 3.40 5.80 2.05 3.45 56 5.25 1.05 3.05 5.15 1.05 3.00 5.25 2.10 3.00 57 6.65 1.15 3.60 6.60 1.15 3.60 6.65 2.30 3.60 58 5.05 1.10 2.80 5.05 1.05 2.75 5.05 2.15 2.80 59 5.30 1.00 2.90 5.30 1.00 2.90 5.30 2.00 2.90 60 6.15 1.15 2.60 6.15 1.05 2.60 6.15 2.20 2.60 61 5.50 1.10 2.80 5.50 1.10 2.95 5.50 2.20 2.95 62 5.60 1.20 3.10 5.55 1.20 3.10 5.60 2.40 3.10 63 5.20 1.00 2.90 5.20 1.00 2.95 5.20 2.00 2.95
98
Table A-8. Continued Mussel
Top Length
Top Height
Top Width
Bottom Length
Bottom Height
Bottom Width
Total Length
Total Height
Total Width
64 6.15 1.15 2.60 6.15 1.05 2.60 6.15 2.20 2.60 65 5.85 0.95 2.50 5.80 0.95 2.35 5.85 1.90 2.50 66 6.25 1.25 3.20 6.20 1.15 3.15 6.25 2.40 3.20 67 5.80 1.00 3.45 5.70 1.05 3.40 5.80 2.05 3.45 68 6.70 1.10 3.40 6.70 1.00 3.40 6.70 2.10 3.40 69 5.30 1.00 3.10 5.25 0.95 3.15 5.30 1.95 3.15 70 4.95 0.90 2.75 4.95 0.95 2.75 4.95 1.85 2.75 71 5.05 1.40 3.20 5.00 1.45 3.20 5.05 2.85 3.20 72 6.15 1.25 3.05 6.20 1.25 3.00 6.20 2.50 3.05 73 4.95 1.40 3.00 4.90 1.45 2.80 4.95 2.85 3.00 74 5.10 1.00 2.75 5.10 1.00 2.75 5.10 2.00 2.75 75 5.85 1.05 2.65 5.90 1.10 2.70 5.90 2.15 2.70 76 6.00 1.15 2.60 6.00 1.10 2.55 6.00 2.25 2.60 77 5.05 0.95 2.35 5.10 0.90 2.30 5.10 1.85 2.53 78 4.95 1.05 3.40 5.00 1.10 3.25 5.00 2.15 3.40 79 5.40 1.30 2.50 5.45 1.35 2.50 5.45 2.65 2.50 80 5.50 1.05 3.10 5.55 1.00 3.15 5.55 2.05 3.15 81 5.55 1.45 3.35 5.50 1.40 3.30 5.55 2.85 3.35 82 5.20 1.25 2.90 5.15 1.25 2.90 5.20 2.50 2.90 83 4.90 0.95 3.10 4.90 0.95 2.90 4.90 1.90 3.10 84 5.25 1.10 3.25 5.25 1.10 3.25 5.25 2.20 3.25 85 6.40 1.05 2.90 6.40 1.05 2.90 6.40 2.10 2.90 86 6.20 1.10 3.10 6.20 1.10 3.10 6.20 2.20 3.10 87 6.70 1.10 3.40 6.70 1.00 3.40 6.70 2.10 3.40 88 6.60 1.20 3.40 6.50 1.15 3.30 6.60 2.35 3.40 89 5.00 1.40 3.05 4.95 1.35 3.00 5.00 2.75 3.05 90 5.00 1.45 2.75 5.05 1.50 2.95 5.05 2.95 2.95 91 6.70 0.95 3.00 6.80 0.95 2.90 6.80 1.90 3.00 92 4.95 1.05 3.25 5.00 1.10 3.35 5.00 2.15 3.35 93 5.05 1.05 2.95 4.70 1.05 2.90 5.05 2.10 2.95 94 5.05 1.10 3.10 5.05 1.10 3.10 5.05 2.20 3.10 95 5.10 1.50 3.20 5.15 1.55 3.25 5.15 3.05 3.25 96 6.20 1.20 3.90 6.15 1.15 3.85 6.20 2.35 3.90 97 6.30 1.00 3.50 6.35 1.05 3.55 6.35 2.05 3.55 98 6.05 1.10 3.10 6.00 1.05 3.05 6.05 2.15 3.10 99 5.60 0.95 2.80 5.60 1.00 2.75 5.60 1.95 2.80 100 5.90 1.35 3.15 5.95 1.30 3.15 5.95 2.65 3.15 Table A-9. Mussel Thickness Measurement in cm (5/22/05) Mussel 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom
1 0.114 0.079 0.244 0.150 0.127 0.104 0.107 0.211 0.102 0.1122 0.094 0.124 0.229 0.114 0.119 0.066 0.107 0.231 0.104 0.1143 0.097 0.109 0.264 0.130 0.137 0.089 0.135 0.284 0.132 0.1244 0.117 0.124 0.358 0.086 0.099 0.109 0.147 0.221 0.117 0.1045 0.071 0.094 0.262 0.127 0.130 0.109 0.124 0.236 0.127 0.1276 0.091 0.109 0.267 0.130 0.124 0.079 0.107 0.254 0.124 0.1277 0.140 0.109 0.165 0.081 0.094 0.104 0.132 0.170 0.112 0.1228 0.084 0.132 0.221 0.124 0.130 0.097 0.127 0.244 0.124 0.1199 0.064 0.094 0.193 0.102 0.109 0.074 0.099 0.201 0.104 0.099
99
Table A-9 Continued Mussel 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom
10 0.089 0.114 2.591 0.079 0.091 0.104 0.109 2.921 0.107 0.09911 0.104 0.130 0.231 0.107 0.109 0.099 0.130 0.241 0.081 0.08112 0.109 0.147 0.221 0.117 0.104 0.104 0.107 0.211 0.102 0.11213 0.107 0.104 0.241 0.130 0.119 0.122 0.112 0.236 0.130 0.13014 0.079 0.130 0.211 0.122 0.112 0.099 0.104 0.206 0.130 0.13215 0.079 0.107 0.206 0.097 0.089 0.135 0.109 0.216 0.119 0.10916 0.089 0.117 0.165 0.119 0.130 0.099 0.117 0.160 0.127 0.12417 0.102 0.104 0.241 0.130 0.124 0.104 0.124 0.236 0.112 0.13018 0.104 0.089 0.267 0.107 0.112 0.104 0.109 2.692 0.107 0.09919 0.109 0.147 0.221 0.117 0.104 0.109 0.117 0.231 0.117 0.11420 0.094 0.117 0.218 0.102 0.132 0.119 0.114 0.208 0.104 0.12721 0.079 0.124 0.196 0.069 0.079 0.091 0.127 0.206 0.084 0.08922 0.064 0.109 0.229 0.114 0.119 0.066 0.109 0.234 0.130 0.12223 0.089 0.132 0.231 0.102 0.119 0.094 0.137 0.221 0.112 0.12224 0.071 0.102 0.165 0.066 0.076 0.079 0.107 0.170 0.079 0.10725 0.074 0.109 0.218 0.114 0.119 0.084 0.117 0.213 0.122 0.10226 0.074 0.097 0.201 0.119 0.135 0.086 0.104 0.193 0.127 0.13727 0.097 0.109 0.264 0.130 0.137 0.089 0.135 0.284 0.132 0.12428 0.130 0.145 0.180 0.074 0.094 0.119 0.130 0.079 0.104 0.11429 0.071 0.094 0.193 0.104 0.099 0.074 0.107 0.180 0.109 0.09930 0.079 0.107 0.165 0.099 0.094 0.079 0.107 0.257 0.107 0.11731 0.079 0.130 0.231 0.107 0.109 0.084 0.119 0.254 0.104 0.11732 0.104 0.150 0.203 0.081 0.130 0.074 0.130 0.246 0.099 0.09433 0.064 0.114 0.231 0.117 0.109 0.097 0.112 0.241 0.124 0.12734 0.089 0.130 0.221 0.130 0.091 0.074 0.104 0.211 0.104 0.11735 0.104 0.147 0.241 0.122 0.109 0.104 0.109 0.236 0.107 0.09736 0.079 0.107 0.254 0.124 0.127 0.081 0.109 0.259 0.127 0.12737 0.104 0.132 0.170 0.112 0.122 0.099 0.137 0.251 0.112 0.13038 0.097 0.127 0.244 0.124 0.119 0.102 0.124 0.277 0.109 0.12439 0.089 0.114 2.591 0.079 0.091 0.094 0.117 2.565 0.089 0.09740 0.104 0.130 0.231 0.107 0.109 0.102 0.124 0.257 0.114 0.11741 0.117 0.124 0.358 0.086 0.099 0.109 0.147 0.246 0.117 0.10442 0.079 0.112 0.229 0.114 0.122 0.079 0.091 0.206 0.104 0.10743 0.089 0.104 0.241 0.130 0.119 0.114 0.109 0.236 0.097 0.09944 0.071 0.109 0.218 0.114 0.119 0.084 0.117 0.213 0.124 0.10245 0.104 0.109 2.667 0.107 0.099 0.102 0.112 2.565 0.102 0.10446 0.099 0.130 0.241 0.081 0.081 0.102 0.132 0.254 0.084 0.099 47 0.117 0.081 0.107 0.130 0.130 0.119 0.109 0.206 0.104 0.09748 0.079 0.130 0.231 0.107 0.109 0.084 0.119 0.254 0.104 0.11749 0.064 0.094 0.193 0.102 0.109 0.074 0.099 0.201 0.104 0.11450 0.097 0.112 0.241 0.124 0.127 0.079 0.102 0.254 0.114 0.12451 0.102 0.130 0.279 0.089 0.104 0.099 0.119 0.259 0.102 0.08952 0.099 0.130 0.241 0.081 0.081 0.102 0.124 0.251 0.099 0.10453 0.104 0.107 0.211 0.102 0.112 0.094 0.097 0.231 0.109 0.10954 0.091 0.102 0.249 0.107 0.130 0.097 0.130 0.244 0.124 0.11955 0.079 0.155 0.279 0.104 0.114 0.112 0.155 0.277 0.097 0.10456 0.107 0.150 0.254 0.089 0.102 0.114 0.145 0.292 0.107 0.11757 0.096 0.109 0.264 0.130 0.137 0.102 0.104 0.234 0.127 0.11958 0.105 0.117 0.257 0.124 0.127 0.130 0.132 0.254 0.104 0.13259 0.097 0.112 0.241 0.124 0.127 0.102 0.124 0.257 0.114 0.117
100
Table A-9 Continued Mussel 1Top 2Top 3Top 4Top 5Top 1Bottom 2Bottom 3Bottom 4Bottom 5Bottom
60 0.074 0.104 0.211 0.104 0.117 0.109 0.147 0.246 0.117 0.10461 0.236 0.086 0.241 0.117 0.104 0.069 0.102 0.231 0.099 0.11262 0.107 0.132 0.221 0.147 0.117 0.109 0.137 0.218 0.127 0.12263 0.084 0.104 0.203 0.124 0.097 0.107 0.089 0.201 0.099 0.10964 0.079 0.094 0.231 0.117 0.109 0.079 0.109 0.208 0.107 0.12465 0.099 0.112 0.203 0.102 0.130 0.084 0.137 0.206 0.104 0.11466 0.102 0.130 0.231 0.069 0.109 0.086 0.107 0.234 0.099 0.09967 0.102 0.132 0.254 0.114 0.091 0.089 0.117 0.221 0.124 0.11768 0.094 0.104 0.198 0.094 0.130 0.124 0.124 0.173 0.119 0.09769 0.091 0.102 0.221 0.140 0.142 0.104 0.122 0.130 0.086 0.10770 0.087 0.104 0.218 0.127 0.137 0.104 0.130 0.231 0.107 0.10971 0.071 0.107 0.244 0.079 0.089 0.074 0.107 0.236 0.109 0.08472 0.102 0.124 0.251 0.099 0.104 0.099 0.130 0.241 0.081 0.08173 0.114 0.109 0.163 0.132 0.130 0.109 0.124 0.160 0.124 0.13574 0.089 0.097 0.262 0.127 0.122 0.091 0.107 0.257 0.127 0.12775 0.069 0.094 0.218 0.086 0.084 0.071 0.104 0.089 0.097 0.10776 0.094 0.097 0.231 0.109 0.109 0.104 0.089 0.267 0.107 0.11277 0.140 0.109 0.165 0.081 0.094 0.104 0.132 0.170 0.102 0.09978 0.066 0.107 0.231 0.104 0.114 0.091 0.109 0.267 0.130 0.12479 0.097 0.119 0.249 0.117 0.099 0.107 0.127 0.244 0.112 0.12280 0.124 0.124 0.173 0.119 0.097 0.074 0.130 0.246 0.099 0.09481 0.079 0.155 0.279 0.104 0.114 0.097 0.112 0.241 0.124 0.12782 0.107 0.150 0.254 0.089 0.102 0.086 0.104 0.218 0.127 0.13783 0.089 0.114 0.218 0.119 0.099 0.107 0.079 0.213 0.097 0.10484 0.107 0.104 0.241 0.104 0.089 0.102 0.094 0.272 0.081 0.10785 0.102 0.127 0.244 0.130 0.119 0.122 0.112 0.236 0.130 0.13086 0.086 0.114 0.180 0.086 0.112 0.066 0.137 0.257 0.081 0.08487 0.089 0.130 0.193 0.127 0.089 0.094 0.107 0.218 0.124 0.12488 0.119 0.107 0.165 0.130 0.130 0.079 0.117 0.201 0.127 0.12489 0.074 0.124 0.231 0.081 0.124 0.084 0.104 0.208 0.094 0.10290 0.091 0.102 0.221 0.140 0.142 0.104 0.122 0.130 0.086 0.10791 0.079 0.130 0.231 0.107 0.109 0.084 0.119 0.254 0.104 0.11792 0.109 0.081 0.262 0.104 0.114 0.086 0.130 0.254 0.122 0.10293 0.119 0.130 0.218 0.130 0.102 0.071 0.107 0.170 0.127 0.13794 0.091 0.094 0.231 0.086 0.099 0.102 0.112 0.244 0.132 0.12495 0.084 0.119 0.254 0.104 0.117 0.079 0.155 0.279 0.104 0.11496 0.086 0.107 0.234 0.099 0.099 0.114 0.109 0.163 0.132 0.13097 0.089 0.117 0.221 0.124 0.117 0.089 0.097 0.262 0.127 0.12298 0.097 0.102 0.241 0.091 0.097 0.104 0.089 0.267 0.107 0.11299 0.102 0.124 0.257 0.114 0.117 0.104 0.150 0.231 0.081 0.130100 0.107 0.150 0.254 0.089 0.102 0.114 0.145 0.292 0.107 0.117
Oyster Irradiation Dose Measurements
Table A-10. Electron Beam irradiated oysters in kGy Oysters External Top Internal External Bottom Internal/Top 1 4.3 4.0 4.3 0.93 2 4.2 4.3 4.1 1.02 3 2.8 1.9 1.6 0.68 4 2.3 1.6 1.4 0.70
101
Table A-10 Continued Oysters External Top Internal External Bottom Internal/Top 5 3.8 3.2 3.0 0.84 6 3.0 2.8 2.7 0.93 7 3.1 2.3 2.5 0.74 8 2.2 1.9 2.0 0.86 9 2.6 1.8 2.5 0.69 10 3.6 2.4 2.1 0.67 11 2.9 2.1 2.4 0.72 12 5.4 2.5 4.8 0.46 13 5.0 4.1 4.3 0.82 14 2.8 2.3 2.7 0.82 15 4.3 2.3 2.3 0.53 16 4.9 4.6 4.3 0.94 17 2.8 2.1 2.5 0.75 18 5.2 5.0 4.9 0.96 19 6.7 4.9 5.5 0.73 20 4.2 4.0 3.7 0.95 21 1.7 2.0 1.6 1.18 22 1.8 2.0 1.8 1.11 23 2.1 1.8 1.4 0.86 24 2.0 2.0 2.0 1.00 25 2.3 2.2 2.1 0.96 26 4.4 3.9 4.3 0.89 27 4.3 3.0 3.6 0.70 28 4.1 4.2 3.9 1.02 29 3.9 3.8 3.7 0.97 30 4.1 3.7 4.1 0.90 31 5.1 2.2 3.1 0.43 32 5.0 5.0 4.4 1.00 33 2.1 2.1 2.1 1.00 34 2.0 2.1 1.9 1.05 35 4.9 4.6 3.9 0.94 36 2.2 1.7 1.7 0.77 37 4.9 4.0 3.7 0.82 38 2.6 2.1 2.1 0.81 39 4.4 4.4 4.4 1.00 40 4.2 4.0 4.2 0.95 41 5.0 4.4 3.6 0.88 42 6.0 3.7 3.1 0.62 43 2.1 1.9 1.6 0.90 44 3.3 1.8 1.9 0.55 45 1.7 1.6 1.5 0.94 46 1.9 1.4 1.7 0.74 47 2.0 1.6 1.9 0.80 48 1.8 1.5 1.8 0.83 49 3.1 1.5 2.2 0.48 50 4.1 2.2 2.1 0.54 51 2.9 2.8 2.5 0.97 52 5.3 5.0 4.5 0.94 53 3.1 3.0 3.1 0.97 54 3.2 2.9 3.2 0.91 55 5.3 5.3 5.1 1.00
102
Table A-10 Continued Oysters External Top Internal External Bottom Internal/Top 56 4.0 3.7 4.0 0.93 57 4.5 4.3 4.0 0.96 58 4.6 4.2 3.1 0.91 59 6.1 4.4 4.4 0.72 60 2.0 1.8 1.7 0.90 61 2.3 2.1 1.5 0.91 62 2.3 1.8 2.0 0.78 63 3.9 3.9 3.7 1.00 64 4.4 4.4 3.7 1.00 65 3.7 3.7 3.1 1.00 66 2.5 1.4 2.2 0.56 67 1.9 2.5 1.9 1.32 68 2.5 1.9 1.5 0.76 69 3.8 3.2 3.8 0.84 70 2.3 2.1 2.3 0.91 71 4.5 4.1 4.0 0.91 72 4.2 4.5 3.9 1.07 73 4.5 4.0 4.2 0.89 74 4.4 4.0 4.0 0.91 75 2.9 1.8 1.9 0.62 76 4.5 4.4 3.8 0.98 77 2.1 2.0 1.9 0.95 78 2.6 2.6 2.5 1.00 79 2.0 1.9 1.9 0.95 80 4.5 3.3 3.9 0.73 81 3.9 3.7 3.3 0.95 82 4.2 3.9 3.0 0.93 83 4.2 3.7 3.9 0.88 84 3.9 4.0 3.2 1.03 85 5.6 5.0 4.6 0.89 86 4.9 3.8 3.9 0.78 87 2.5 2.2 2.3 0.88 88 2.2 2.3 2.1 1.05 89 2.4 1.5 2.0 0.63 90 3.7 3.7 3.6 1.00 91 3.9 4.6 3.7 1.18 92 3.8 3.7 3.7 0.97 93 1.6 1.4 1.5 0.88 94 2.2 1.6 2.0 0.73 95 4.8 4.0 4.1 0.83 96 4.0 4.2 3.7 1.05 97 4.3 3.6 3.7 0.84 98 3.7 2.4 3.0 0.65 99 2.3 2.0 2.3 0.87 100 1.8 2.0 1.6 1.11 Table A-11. X-ray Irradiated Oysters in kGy Oysters External Top Internal External Bottom Internal/Top 1 3.7 4.2 3.4 1.14 2 4.2 4.1 4.1 0.98 3 2.0 1.4 1.9 0.70
103
Table A-11 Continued Oysters External Top Internal External Bottom Internal/Top 4 1.8 1.5 1.8 0.83 5 5.1 5.6 5.1 1.10 6 4.9 3.7 3.9 0.76 7 3.1 2.3 2.5 0.74 8 1.9 1.4 1.6 0.74 9 1.5 1.7 1.3 1.13 10 1.7 1.2 1.5 0.71 11 1.8 1.6 1.5 0.89 12 4.1 4.3 3.6 1.05 13 3.8 3.6 3.7 0.95 14 1.6 1.8 1.5 1.13 15 4.3 2.3 2.3 0.53 16 4.4 4.2 4.2 0.95 17 2.2 1.5 1.5 0.68 18 4.6 3.6 3.7 0.78 19 4.2 3.8 3.8 0.90 20 6.9 5.1 5.0 0.74 21 1.5 1.7 1.5 1.13 22 1.9 1.6 1.8 0.84 23 2.1 1.8 1.4 0.86 24 1.9 1.8 1.8 0.95 25 3.0 1.5 1.4 0.50 26 4.1 4.0 3.6 0.98 27 4.8 4.2 3.8 0.88 28 3.8 3.8 3.6 1.00 29 5.0 6.5 3.7 1.30 30 4.9 4.8 4.6 0.98 31 4.1 3.7 4.1 0.90 32 4.2 4.0 4.0 0.95 33 1.3 1.2 1.3 0.92 34 2.8 1.5 1.5 0.54 35 3.7 3.4 3.7 0.92 36 1.9 1.5 1.2 0.79 37 4.4 4.0 3.9 0.91 38 2.6 2.1 2.1 0.81 39 6.0 6.9 5.2 1.15 40 4.0 3.4 4.0 0.85 41 4.3 3.7 4.2 0.86 42 6.3 5.6 5.7 0.89 43 2.0 1.3 2.0 0.65 44 1.7 2.4 1.5 1.41 45 1.7 1.7 1.5 1.00 46 2.0 1.6 1.9 0.80 47 1.5 1.4 1.5 0.93 48 2.0 2.4 1.4 1.20 49 2.5 1.5 1.8 0.60 50 1.5 1.4 1.3 0.93 51 1.7 1.5 1.5 0.88 52 4.2 4.5 4.1 1.07 53 1.6 1.3 1.2 0.81 54 1.8 1.7 1.7 0.94
104
Table A-11 Continued Oysters External Top Internal External Bottom Internal/Top 55 4.3 4.0 4.3 0.93 56 4.8 4.1 4.6 0.85 57 4.5 3.8 3.7 0.84 58 5.1 6.4 5.0 1.25 59 4.8 3.4 3.4 0.71 60 2.3 1.2 1.5 0.52 61 1.4 1.2 1.3 0.86 62 1.6 1.6 1.3 1.00 63 4.1 4.1 3.6 1.00 64 3.8 4.0 3.2 1.05 65 4.9 3.9 3.8 0.80 66 2.1 1.5 1.5 0.71 67 1.5 1.2 1.4 0.80 68 2.5 1.9 1.5 0.76 69 4.6 4.8 4.4 1.04 70 2.2 1.4 2.0 0.64 71 3.6 3.4 3.2 0.94 72 4.1 3.4 3.9 0.83 73 4.1 4.0 4.0 0.98 74 5.2 4.1 4.0 0.79 75 1.5 1.5 1.4 1.00 76 4.2 3.7 4.0 0.88 77 2.1 2.0 1.9 0.95 78 2.6 2.6 2.5 1.00 79 3.7 4.0 3.6 1.08 80 4.3 3.8 3.8 0.88 81 3.3 3.6 3.1 1.09 82 4.5 4.5 4.4 1.00 83 4.4 4.8 3.4 1.09 84 3.9 3.4 3.3 0.87 85 5.6 5.5 5.5 0.98 86 4.1 3.8 4.0 0.93 87 2.5 2.2 2.3 0.88 88 1.8 1.3 1.6 0.72 89 1.5 2.6 1.5 1.73 90 4.0 3.6 3.6 0.90 91 3.7 3.7 3.6 1.00 92 3.8 3.7 3.4 0.97 93 2.2 1.5 2.0 0.68 94 1.8 2.2 1.2 1.22 95 6.4 4.3 3.7 0.67 96 3.7 3.2 3.6 0.86 97 3.4 3.4 3.4 1.00 98 1.6 1.4 1.4 0.88 99 1.8 1.5 1.4 0.83 100 1.6 1.9 1.5 1.19 Table A-12. Gamma Ray Irradiated Oysters in kGy Oysters External Top Internal External Bottom Internal/Top 1 3.9 3.8 3.7 0.97 2 4.3 4.3 4.2 1.00
105
Table A-12 Continued Oysters External Top Internal External Bottom Internal/Top 3 1.6 1.3 1.5 0.81 4 1.5 1.4 1.4 0.93 5 4.5 4.1 3.9 0.91 6 3.7 3.7 3.4 1.00 7 3.1 3.0 2.9 0.97 8 2.0 1.6 1.6 0.80 9 2.7 2.3 2.1 0.85 10 2.2 1.8 1.7 0.82 11 1.7 1.6 1.3 0.94 12 5.0 4.6 4.6 0.92 13 4.0 3.8 3.7 0.95 14 1.8 1.5 1.4 0.83 15 3.3 2.8 2.5 0.85 16 4.3 4.2 3.9 0.98 17 3.1 2.3 2.1 0.74 18 4.9 4.6 4.5 0.94 19 4.4 4.0 4.0 0.91 20 3.9 3.7 3.7 0.95 21 2.0 1.8 1.7 0.90 22 1.9 1.8 1.7 0.95 23 3.1 2.7 2.7 0.87 24 1.8 1.6 1.4 0.89 25 2.3 2.0 1.8 0.87 26 3.8 3.7 3.7 0.97 27 4.5 4.4 4.4 0.98 28 4.4 4.2 4.1 0.95 29 4.0 3.9 3.8 0.98 30 4.1 3.9 3.8 0.95 31 2.9 2.8 2.8 0.97 32 3.9 3.9 3.8 1.00 33 2.1 1.8 1.8 0.86 34 2.0 2.0 2.0 1.00 35 4.6 4.1 4.0 0.89 36 2.4 1.9 1.7 0.79 37 3.9 3.8 3.3 0.97 38 3.1 2.9 2.8 0.94 39 3.8 3.7 3.4 0.97 40 4.0 3.8 3.4 0.95 41 3.7 3.6 3.4 0.97 42 4.2 3.9 3.7 0.93 43 2.1 2.1 2.0 1.00 44 2.0 1.8 1.7 0.90 45 2.0 2.0 1.8 1.00 46 4.4 4.4 3.4 1.00 47 2.1 1.9 1.7 0.90 48 2.0 1.5 1.5 0.75 49 2.2 2.0 2.0 0.91 50 2.2 2.1 1.9 0.95 51 1.8 1.8 1.7 1.00 52 4.5 4.5 4.2 1.00 53 2.5 2.2 2.1 0.88
106
Table A-12 Continued Oysters External Top Internal External Bottom Internal/Top 54 2.0 1.9 1.8 0.95 55 4.6 4.2 4.1 0.91 56 4.6 4.4 4.4 0.96 57 4.4 4.3 4.2 0.98 58 4.0 3.9 3.7 0.98 59 4.6 4.5 4.0 0.98 60 1.9 1.8 1.6 0.95 61 1.8 1.8 1.8 1.00 62 1.4 1.2 1.3 0.86 63 4.0 3.9 3.7 0.98 64 4.4 4.3 4.2 0.98 65 4.3 3.8 3.8 0.88 66 2.3 1.9 1.9 0.83 67 1.3 1.2 1.2 0.92 68 4.2 4.1 3.9 0.98 69 5.1 4.9 4.9 0.96 70 1.3 1.2 1.2 0.92 71 5.1 4.9 4.9 0.96 72 5.0 4.6 4.9 0.92 73 4.2 4.2 4.1 1.00 74 4.8 4.2 4.2 0.88 75 2.5 2.1 1.9 0.84 76 4.0 3.8 3.6 0.95 77 3.3 2.9 2.7 0.88 78 2.8 2.8 2.7 1.00 79 4.2 4.2 4.1 1.00 80 3.8 3.7 3.7 0.97 81 5.5 5.2 5.1 0.95 82 3.8 3.7 3.7 0.97 83 4.6 4.6 4.5 1.00 84 4.8 4.6 4.6 0.96 85 3.8 3.8 3.7 1.00 86 4.9 4.6 4.5 0.94 87 3.2 2.8 2.8 0.88 88 1.8 1.6 1.5 0.89 89 1.8 1.7 1.6 0.94 90 4.6 4.6 4.3 1.00 91 4.8 4.6 4.0 0.96 92 4.4 4.1 4.0 0.93 93 2.3 2.1 2.0 0.91 94 2.0 1.7 1.5 0.85 95 4.1 3.9 3.7 0.95 96 3.9 3.8 3.7 0.97 97 4.3 4.2 4.1 0.98 98 1.3 1.3 1.2 1.00 99 1.8 1.8 1.7 1.00 100 1.5 1.5 1.3 1.00
107
Clam Irradiated Dose Measurements
Table A-13. Electron Beam Irradiated Clams in kGy Clams External Top Internal External Bottom Internal/Top 1 4.1 3.9 3.4 0.95 2 4.1 3.9 3.2 0.95 3 2.7 1.8 1.5 0.67 4 2.6 1.6 1.5 0.62 5 3.9 3.8 3.9 0.97 6 3.2 1.6 2.6 0.50 7 3.9 3.3 3.8 0.85 8 3.4 3.7 3.3 1.09 9 4.1 3.9 3.4 0.95 10 3.8 3.7 3.6 0.97 11 2.4 1.7 1.6 0.71 12 3.9 3.8 3.2 0.97 13 2.4 1.8 2.3 0.75 14 3.8 3.8 3.8 1.00 15 3.2 3.7 3.2 1.16 16 2.3 1.7 1.7 0.74 17 3.4 3.7 3.2 1.09 18 3.8 2.2 3.6 0.58 19 3.8 3.4 1.5 0.89 20 3.9 3.7 3.6 0.95 21 2.0 1.9 2 0.95 22 3.6 3.6 3.6 1.00 23 1.8 1.5 1.8 0.83 24 2.9 1.7 2.1 0.59 25 4.5 3.7 3.6 0.82 26 3.7 3.4 3.2 0.92 27 4.1 4.2 3.9 1.02 28 3.8 3.8 3.3 1.00 29 4.0 3.8 3.4 0.95 30 1.8 1.8 1.7 1.00 31 2.1 1.8 1.9 0.86 32 2.2 1.9 1.7 0.86 33 4.6 3.8 4.5 0.83 34 3.4 3.7 3.4 1.09 35 3.8 4.1 3.6 1.08 36 1.9 1.2 1.8 0.63 37 1.7 1.9 1.6 1.12 38 3.3 3.7 3.2 1.12 39 4.3 3.7 4 0.86 40 1.7 1.7 1.5 1.00 41 4.0 4.1 2.9 1.03 42 1.7 1.8 1.5 1.06 43 3.6 3.4 3.4 0.94 44 3.8 3.7 3.6 0.97 45 2.8 1.7 2.3 0.61 46 3.6 3.7 3.3 1.03 47 3.4 3.6 3.3 1.06 48 1.8 1.7 1.7 0.94 49 2.5 2.0 2 0.80
108
Table A-13. Continued Clams External Top Internal External Bottom Internal/Top 50 1.8 1.7 1.7 0.94 51 2.4 1.5 2 0.63 52 2.2 1.8 1.8 0.82 53 2.3 1.7 1.8 0.74 54 1.8 1.7 1.3 0.94 55 3.8 3.6 3.6 0.95 56 4.5 3.3 3.8 0.73 57 1.8 1.7 1.8 0.94 58 3.9 3.2 3.6 0.82 59 2.0 1.8 1.9 0.90 60 4.1 3.4 2 0.83 61 3.8 4.0 3.2 1.05 62 4.0 3.7 2.6 0.93 63 3.7 4.0 3.4 1.08 64 3.6 3.8 3.3 1.06 65 1.7 1.5 1.6 0.88 66 2.3 1.4 1.6 0.61 67 3.8 3.8 3.4 1.00 68 2.4 1.5 1.6 0.63 69 2.3 1.9 1.9 0.83 70 3.8 3.6 3.4 0.95 71 2.2 1.6 1.6 0.73 72 4.1 4.1 3.9 1.00 73 4.2 3.1 3.7 0.74 74 2.0 1.4 1.3 0.70 75 2.1 1.5 1.4 0.71 76 1.8 1.7 1.7 0.94 77 1.7 1.8 1.6 1.06 78 3.1 1.7 1.6 0.55 79 4.2 3.2 2.9 0.76 80 2.1 1.6 1.7 0.76 81 3.7 3.7 3.2 1.00 82 3.9 2.9 3.9 0.74 83 1.9 1.7 1.8 0.89 84 3.8 3.8 3.8 1.00 85 2.3 1.9 2.1 0.83 86 1.9 1.8 1.8 0.95 87 3.8 3.4 3.4 0.89 88 4.0 3.9 3.8 0.98 89 1.6 2.0 1.3 1.25 90 2.6 1.4 1.7 0.54 91 4.5 4.0 3.7 0.89 92 4.5 3.2 3.8 0.71 93 1.8 1.7 1.6 0.94 94 1.5 1.4 1.5 0.93 95 2.7 1.9 1.8 0.70 96 2.3 1.7 1.8 0.74 97 2.3 2.0 1.7 0.87 98 2.3 1.7 1.6 0.74 99 3.7 3.6 3.3 0.97 100 2.1 1.3 2.1 0.62
109
Table A-14. X-ray Irradiated Clams in kGy Clams External Top Internal External Bottom Internal/Top 1 4.3 4.3 3.1 1.00 2 4.0 4.0 2.9 1.00 3 2.7 1.8 1.5 0.67 4 2.6 2.0 2.4 0.77 5 4.2 4.9 3.8 1.17 6 4.3 4.3 4.0 1.00 7 4.4 3.8 3.8 0.86 8 4.0 3.8 4.0 0.95 9 4.4 3.7 3.8 0.84 10 6.3 4.4 6.0 0.70 11 2.4 2.4 2.2 1.00 12 4.5 5.1 4.4 1.13 13 1.7 1.7 1.6 1.00 14 4.2 4.0 4.1 0.95 15 4.1 3.9 3.7 0.95 16 2.5 2.1 2.4 0.84 17 5.4 5.4 4.9 1.00 18 4.0 4.0 3.9 1.00 19 4.3 4.2 4.2 0.98 20 3.8 3.7 3.7 0.97 21 1.5 1.7 1.5 1.13 22 4.0 4.2 4.0 1.05 23 2.4 2.3 2.3 0.96 24 3.1 2.4 2.1 0.77 25 4.0 3.9 3.8 0.98 26 3.8 3.8 3.8 1.00 27 4.9 4.5 3.8 0.92 28 4.2 3.8 3.9 0.90 29 4.3 4.0 4.1 0.93 30 1.9 1.6 1.6 0.84 31 3.9 2.7 2.5 0.69 32 1.7 1.4 1.6 0.82 33 4.5 4.2 4.2 0.93 34 4.9 4.1 4.4 0.84 35 4.2 3.9 4.0 0.93 36 2.3 1.8 1.9 0.78 37 1.6 1.6 1.3 1.00 38 4.2 4.2 3.8 1.00 39 3.9 4.0 3.3 1.03 40 2.4 2.2 2.2 0.92 41 5.0 4.5 4.6 0.90 42 1.4 1.6 1.2 1.14 43 4.8 4.4 3.9 0.92 44 4.6 3.8 4.0 0.83 45 1.7 1.8 1.5 1.06 46 5.1 4.2 4.2 0.82 47 4.6 4.8 4.0 1.04 48 2.5 3.0 1.7 1.20 49 2.1 1.6 1.7 0.76 50 4.2 2.4 2.4 0.57 51 2.1 2.1 2.1 1.00
110
Table A-14 Continued Clams External Top Internal External Bottom Internal/Top 52 2.1 1.4 2.1 0.67 53 3.4 2.3 2.4 0.68 54 2.7 1.5 2.0 0.56 55 4.0 4.6 3.9 1.15 56 4.2 3.9 4.2 0.93 57 2.4 2.2 2.1 0.92 58 4.5 3.9 4.0 0.87 59 1.6 1.5 1.5 0.94 60 4.4 4.2 3.9 0.95 61 4.0 4.0 3.8 1.00 62 4.3 4.3 4.2 1.00 63 4.2 4.3 3.6 1.02 64 3.7 3.8 3.6 1.03 65 2.2 1.8 2.1 0.82 66 2.5 1.9 2.2 0.76 67 4.8 4.1 3.8 0.85 68 2.4 2.2 2.3 0.92 69 1.6 1.9 1.6 1.19 70 3.8 3.8 3.7 1.00 71 1.6 2.6 1.6 1.63 72 4.5 4.5 4.4 1.00 73 3.8 3.9 2.6 1.03 74 1.7 1.6 1.6 0.94 75 1.7 1.6 1.4 0.94 76 1.7 2.1 1.6 1.24 77 2.3 2.4 1.4 1.04 78 2.9 2.4 2.6 0.83 79 4.3 3.9 4.0 0.91 80 1.6 1.5 1.5 0.94 81 5.2 5.3 4.6 1.02 82 4.5 4.1 4.3 0.91 83 3.1 2.5 2.4 0.81 84 4.8 4.3 4.4 0.90 85 1.7 1.5 1.4 0.88 86 1.7 1.5 1.3 0.88 87 4.8 4.0 3.3 0.83 88 4.8 4.2 4.8 0.88 89 1.9 1.5 1.4 0.79 90 3.1 1.8 3.1 0.58 91 4.5 3.9 3.9 0.87 92 4.3 4.2 4.2 0.98 93 2.0 1.9 1.6 0.95 94 2.3 2.3 2.1 1.00 95 1.9 1.3 1.3 0.68 96 1.2 1.2 1.2 1.00 97 1.7 1.9 1.7 1.12 98 2.3 2.3 1.9 1.00 99 4.4 3.9 3.6 0.89 100 2.3 2.1 2.2 0.91
111
Table A-15. Gamma Ray Irradiated Clams in kGy Clams External Top Internal External Bottom Internal/Top 1 4.8 4.2 4.0 0.88 2 4.4 4.4 4.0 1.00 3 3.3 3.1 2.9 0.94 4 1.6 1.5 1.2 0.94 5 4.5 4.3 4.3 0.96 6 4.5 4.5 4.3 1.00 7 4.9 4.4 4.4 0.90 8 5.1 5.1 4.9 1.00 9 5.0 4.2 4.2 0.84 10 4.6 4.5 4.4 0.98 11 1.6 1.6 1.3 1.00 12 4.5 4.4 4.4 0.98 13 2.2 2.0 1.9 0.91 14 4.2 4.1 3.9 0.98 15 4.3 3.8 4.3 0.88 16 2.4 1.9 2.2 0.79 17 4.9 4.2 4.1 0.86 18 4.2 4.2 3.7 1.00 19 4.6 4.1 4.0 0.89 20 5.2 4.9 5.1 0.94 21 2.1 1.9 1.9 0.90 22 5.1 4.6 4.5 0.90 23 1.9 1.8 1.3 0.95 24 1.9 1.9 1.8 1.00 25 4.6 4.5 4.0 0.98 26 4.6 4.6 4.4 1.00 27 4.6 4.5 4.3 0.98 28 4.3 4.3 4.1 1.00 29 5.1 4.9 5.1 0.96 30 1.7 1.7 1.5 1.00 31 2.3 2.2 2.1 0.96 32 2.1 1.8 1.4 0.86 33 4.5 4.1 4.0 0.91 34 5.1 5.0 4.6 0.98 35 5.0 4.9 4.8 0.98 36 2.9 2.6 2.6 0.90 37 1.6 1.5 1.5 0.94 38 4.7 4.7 4.3 1.00 39 4.5 3.8 4.4 0.84 40 2.0 1.6 1.4 0.80 41 4.4 4.4 4.2 1.00 42 2.0 1.9 1.9 0.95 43 4.6 4.6 4.5 1.00 44 4.4 4.2 4.0 0.95 45 2.3 2.2 2.2 0.96 46 4.8 4.4 4.1 0.92 47 4.3 4.2 3.8 0.98 48 1.8 1.7 1.7 0.94 49 2.0 2.0 1.9 1.00 50 1.7 1.7 1.6 1.00
112
Table A-15 Continued Clams External Top Internal External Bottom Internal/Top 51 2.0 1.8 1.2 0.90 52 1.9 1.8 1.8 0.95 53 2.1 2.0 1.8 0.95 54 2.6 2.1 2.1 0.81 55 4.5 4.2 4.0 0.93 56 4.6 4.4 4.2 0.96 57 2.0 1.7 1.6 0.85 58 4.9 4.8 4.5 0.98 59 2.4 2.3 1.9 0.96 60 4.1 4.0 3.9 0.98 61 4.5 4.2 4.2 0.93 62 4.4 4.3 4.2 0.98 63 4.6 4.6 4.4 1.00 64 4.8 4.0 3.9 0.83 65 2.1 2.1 1.5 1.00 66 1.5 1.4 1.3 0.93 67 4.2 4.2 4.1 1.00 68 2.0 1.7 1.2 0.85 69 2.3 1.5 1.2 0.65 70 4.6 4.5 4.4 0.98 71 2.1 2.0 2.0 0.95 72 4.8 4.4 3.7 0.92 73 5.0 4.3 4.3 0.86 74 1.8 1.8 1.5 1.00 75 2.1 1.7 1.4 0.81 76 2.1 2.0 1.8 0.95 77 2.4 1.8 1.6 0.75 78 1.9 1.8 1.7 0.95 79 4.1 4.1 3.9 1.00 80 2.6 2.3 2.1 0.88 81 4.6 4.6 3.8 1.00 82 4.8 4.5 4.3 0.94 83 3.3 2.0 1.6 0.61 84 4.6 4.6 4.6 1.00 85 1.7 1.9 1.5 1.12 86 1.7 1.7 1.5 1.00 87 4.3 4.2 4.2 0.98 88 4.3 4.1 4.2 0.95 89 1.8 1.5 1.2 0.83 90 2.3 2.0 1.9 0.87 91 4.4 4.3 4.2 0.98 92 4.5 4.4 4.2 0.98 93 1.7 1.5 1.4 0.88 94 1.8 1.7 1.6 0.94 95 2.3 2.2 2.2 0.96 96 2.3 2.3 2.1 1.00 97 1.5 1.5 1.3 1.00 98 2.4 2.0 1.9 0.83 99 4.4 4.0 4.0 0.91 100 1.8 1.5 1.4 0.83
113
Mussel Irradiation Dose Measurements
Table A-16. Electron Beam irradiated mussels in kGy Mussels External Top Internal External Bottom Internal/Top 1 2.0 1.6 1.6 0.80 2 3.2 3.2 1.6 1.00 3 2.0 1.4 1.3 0.70 4 1.9 2.1 1.6 1.11 5 3.2 3.0 2.7 0.94 6 1.6 1.5 1.5 0.94 7 3.2 3.1 3.0 0.97 8 3.3 3.2 3.0 0.97 9 1.6 1.6 1.6 1.00 10 3.7 3.4 3.1 0.92 11 1.6 1.2 1.5 0.75 12 3.2 3.3 3.2 1.03 13 2.2 1.4 1.3 0.64 14 3.8 2.9 3.2 0.76 15 1.7 1.3 1.3 0.76 16 3.0 1.3 1.2 0.43 17 1.3 1.6 1.2 1.23 18 3.0 2.7 2.9 0.90 19 1.8 1.5 1.6 0.83 20 1.4 1.3 1.2 0.93 21 1.5 1.5 1.2 1.00 22 3.2 3.1 2.9 0.97 23 1.4 1.8 1.4 1.29 24 1.6 1.6 1.4 1.00 25 1.9 1.8 1.2 0.95 26 2.7 2.8 2.6 1.04 27 3.2 2.8 2.7 0.88 28 1.6 1.5 1.4 0.94 29 1.6 1.5 1.4 0.94 30 1.6 2.1 1.6 1.31 31 1.4 1.6 1.4 1.14 32 1.7 1.6 1.7 0.94 33 3.4 2.9 2.7 0.85 34 3.2 4.1 2.7 1.28 35 3.4 3.4 2.6 1.00 36 3.3 3.2 3.2 0.97 37 3.4 3.7 2.3 1.09 38 3.2 3.0 3.0 0.94 39 1.7 1.5 1.3 0.88 40 1.4 2.0 1.2 1.43 41 1.6 1.6 1.5 1.00 42 3.2 2.8 2.8 0.88 43 3.0 3.1 3.0 1.03 44 1.6 1.6 1.5 1.00 45 1.7 1.3 1.5 0.76 46 1.3 1.5 1.3 1.15 47 2.9 3.7 2.8 1.28 48 3.3 2.9 3.2 0.88 49 1.5 1.5 1.4 1.00
114
Table A-16 Continued Mussels External Top Internal External Bottom Internal/Top 50 2.9 2.7 2.7 0.93 51 2.3 1.5 2.1 0.65 52 3.0 3.1 2.9 1.03 53 1.7 1.6 1.7 0.94 54 3.3 3.1 2.8 0.94 55 3.1 3.0 3.1 0.97 56 3.2 3.4 3.1 1.06 57 3.2 3.0 3.1 0.94 58 2.8 3.0 2.5 1.07 59 3.2 3.0 3.1 0.94 60 1.5 1.6 1.2 1.07 61 1.6 1.2 1.3 0.75 62 1.8 1.4 1.5 0.78 63 3.1 2.6 2.5 0.84 64 2.8 2.7 2.8 0.96 65 3.3 3.2 2.9 0.97 66 3.2 3.4 2.5 1.06 67 3.0 2.3 2.6 0.77 68 1.5 1.5 1.4 1.00 69 1.6 1.2 1.6 0.75 70 1.5 1.4 1.2 0.93 71 1.9 1.6 1.5 0.84 72 1.7 1.7 1.7 1.00 73 4.2 3.1 3.3 0.74 74 3.1 3.1 2.9 1.00 75 3.3 3.2 3.2 0.97 76 1.7 1.9 1.7 1.12 77 3.1 2.8 2.9 0.90 78 1.5 1.6 1.3 1.07 79 3.7 3.4 3.0 0.92 80 1.7 2.1 1.6 1.24 81 3.7 1.5 3.0 0.41 82 3.6 3.2 3.3 0.89 83 3.1 2.8 2.8 0.90 84 1.4 1.3 1.3 0.93 85 1.4 1.7 1.4 1.21 86 1.4 1.8 1.3 1.29 87 3.3 3.6 2.6 1.09 88 1.7 1.4 1.4 0.82 89 1.7 1.4 1.2 0.82 90 1.7 1.4 1.4 0.82 91 3.4 3.1 3.1 0.91 92 3.4 3.1 2.5 0.91 93 2.9 3.2 2.4 1.10 94 1.6 1.4 1.3 0.88 95 3.4 3.1 3.1 0.91 96 3.1 3.0 3.1 0.97 97 1.4 2.1 1.4 1.50 98 3.2 3.3 3.2 1.03 99 3.3 3.0 3.3 0.91 100 3.2 3.2 3.2 1.00
115
Table A-17. X-ray Irradiated Mussels in kGy Mussels External Top Internal External Bottom Internal/Top 1 1.7 1.6 1.7 0.94 2 3.9 3.8 3.7 0.97 3 2.0 1.6 1.6 0.80 4 1.9 2.0 1.9 1.05 5 4.5 4.1 4.0 0.91 6 1.6 1.9 1.5 1.19 7 3.9 3.8 3.8 0.97 8 4.0 4.2 3.8 1.05 9 2.0 1.7 1.7 0.85 10 5.0 5.0 4.9 1.00 11 2.0 1.9 1.7 0.95 12 4.6 4.5 4.1 0.98 13 1.8 2.2 1.8 1.22 14 4.8 5.0 4.4 1.04 15 1.7 1.9 1.6 1.12 16 4.4 4.3 4.2 0.98 17 1.9 1.7 1.6 0.89 18 4.6 4.9 4.5 1.07 19 1.9 2.2 1.7 1.16 20 1.7 1.6 1.6 0.94 21 1.8 1.9 1.7 1.06 22 4.4 4.3 4.2 0.98 23 1.9 1.6 1.6 0.84 24 1.8 1.8 1.7 1.00 25 1.8 1.8 1.6 1.00 26 4.9 4.6 4.3 0.94 27 4.6 4.6 4.6 1.00 28 1.6 1.6 1.6 1.00 29 1.8 1.8 1.8 1.00 30 1.8 1.7 1.7 0.94 31 1.9 1.9 1.8 1.00 32 1.7 2.0 1.6 1.18 33 4.5 4.6 4.3 1.02 34 3.7 4.0 3.6 1.08 35 3.9 3.8 3.6 0.97 36 4.6 4.6 4.6 1.00 37 4.6 4.4 4.5 0.96 38 4.4 4.4 4.3 1.00 39 1.9 2.1 1.8 1.11 40 1.7 1.7 1.7 1.00 41 1.8 1.6 1.6 0.89 42 4.3 4.3 4.2 1.00 43 4.0 4.1 4.0 1.03 44 1.7 1.6 1.6 0.94 45 1.6 1.9 1.5 1.19 46 1.8 1.8 1.7 1.00 47 4.1 4.4 3.9 1.07 48 3.6 3.8 3.6 1.06 49 1.6 1.6 1.6 1.00 50 4.2 4.6 4.2 1.10 51 2.0 2.0 1.8 1.00
116
Table A-17 Continued Mussels External Top Internal External Bottom Internal/Top 52 4.5 4.5 4.3 1.00 53 2.1 1.9 1.7 0.90 54 4.0 4.0 3.9 1.00 55 4.6 4.4 4.3 0.96 56 4.8 4.5 0.0 0.94 57 4.4 4.4 4.2 1.00 58 4.6 4.3 4.1 0.93 59 4.2 4.2 4.2 1.00 60 1.8 1.9 1.7 1.06 61 1.6 1.9 1.6 1.19 62 1.7 2.0 1.6 1.18 63 4.8 5.0 4.8 1.04 64 4.6 4.5 4.5 0.98 65 4.3 4.5 4.1 1.05 66 4.5 4.4 4.3 0.98 67 4.1 4.2 3.9 1.02 68 2.0 1.8 1.6 0.90 69 2.0 1.9 1.7 0.95 70 1.9 1.8 1.9 0.95 71 1.9 1.8 1.9 0.95 72 1.8 1.8 1.6 1.00 73 5.0 4.9 4.9 0.98 74 3.9 3.8 3.6 0.97 75 3.8 3.8 3.4 1.00 76 1.7 1.9 1.6 1.12 77 3.7 3.9 3.4 1.05 78 1.7 1.6 1.5 0.94 79 4.0 4.2 3.9 1.05 80 2.0 1.7 1.6 0.85 81 4.6 4.9 4.5 1.07 82 4.2 4.4 0.0 1.05 83 4.6 4.4 4.4 0.96 84 1.7 2.0 1.6 1.18 85 1.9 1.5 1.7 0.79 86 1.9 1.7 1.6 0.89 87 5.2 4.5 5.2 0.87 88 1.9 1.7 1.7 0.89 89 1.6 1.8 1.6 1.13 90 1.7 1.9 1.6 1.12 91 4.5 4.5 4.5 1.00 92 3.8 3.4 3.6 0.89 93 3.7 3.8 3.6 1.03 94 1.6 1.9 1.6 1.19 95 4.3 4.4 4.3 1.02 96 4.6 4.5 4.1 0.98 97 1.8 1.7 1.6 0.94 98 4.2 4.3 4.1 1.02 99 4.8 4.9 4.5 1.02 100 4.1 4.0 4.1 0.98
117
Table A-18. Gamma Ray Irradiated Mussels in kGy Mussels External Top Internal External Bottom Internal/Top 1 1.7 1.7 1.6 1.00 2 3.9 3.8 3.7 0.97 3 2.0 1.6 1.6 0.80 4 2.0 1.9 1.9 0.95 5 4.5 4.4 4.3 0.98 6 1.9 1.6 1.5 0.84 7 3.9 3.8 3.8 0.97 8 4.2 4.0 3.8 0.95 9 2.0 1.7 1.7 0.85 10 5.0 5.0 4.9 1.00 11 2.0 1.9 1.7 0.95 12 4.6 4.5 4.1 0.98 13 2.2 1.8 1.8 0.82 14 5.0 4.8 4.4 0.96 15 1.9 1.7 1.6 0.89 16 4.4 4.3 4.2 0.98 17 1.8 1.6 1.6 0.89 18 4.9 4.6 4.5 0.94 19 2.2 1.9 1.7 0.86 20 1.7 1.6 1.6 0.94 21 1.9 1.8 1.7 0.95 22 4.6 4.5 4.4 0.98 23 1.9 1.6 1.6 0.84 24 1.9 1.8 1.7 0.95 25 1.8 1.6 1.6 0.89 26 4.9 4.6 4.3 0.94 27 4.6 4.6 4.6 1.00 28 1.6 1.6 1.6 1.00 29 2.0 1.8 2.0 0.90 30 1.8 1.7 1.7 0.94 31 1.9 1.8 1.8 0.95 32 2.0 1.7 1.6 0.85 33 4.6 4.5 4.3 0.98 34 4.0 3.7 3.6 0.93 35 3.9 3.8 3.6 0.97 36 4.6 4.6 4.6 1.00 37 4.6 4.5 4.4 0.98 38 4.4 4.4 4.3 1.00 39 2.1 1.9 1.8 0.90 40 1.7 1.7 1.7 1.00 41 1.7 1.6 1.6 0.94 42 4.3 4.3 4.2 1.00 43 4.1 4.0 4.0 0.98 44 1.7 1.6 1.6 0.94 45 1.9 1.6 1.5 0.84 46 1.8 1.8 1.7 1.00 47 4.4 4.1 3.9 0.93 48 3.8 3.6 3.6 0.95 49 1.6 1.6 1.6 1.00 50 4.6 4.2 4.2 0.91 51 2.0 2.0 1.8 1.00
118
Table A-18 Continued Mussels External Top Internal External Bottom Internal/Top 52 4.5 4.5 4.3 1.00 53 2.0 1.9 1.7 0.95 54 4.0 4.0 3.9 1.00 55 4.6 4.4 4.3 0.96 56 4.8 4.6 4.5 0.96 57 4.4 4.4 4.2 1.00 58 4.3 4.1 4.1 0.95 59 4.2 4.2 4.2 1.00 60 1.9 1.8 1.7 0.95 61 1.9 1.6 1.6 0.84 62 2.0 1.7 1.6 0.85 63 5.0 4.8 4.8 0.96 64 4.6 4.5 4.5 0.98 65 4.5 4.3 4.1 0.96 66 4.5 4.4 4.3 0.98 67 4.2 4.1 3.9 0.98 68 2.0 1.8 1.6 0.90 69 2.0 1.9 1.7 0.95 70 1.9 1.9 1.8 1.00 71 1.9 1.8 1.8 0.95 72 1.8 1.8 1.6 1.00 73 5.0 4.9 4.9 0.98 74 3.9 3.8 3.6 0.97 75 3.8 3.8 3.4 1.00 76 1.9 1.7 1.6 0.89 77 3.9 3.7 3.4 0.95 78 1.7 1.6 1.5 0.94 79 4.2 4.0 3.9 0.95 80 2.0 1.7 1.6 0.85 81 4.9 4.6 4.5 0.94 82 4.5 4.4 4.2 0.98 83 4.6 4.4 4.4 0.96 84 2.0 1.7 1.6 0.85 85 1.9 1.7 1.5 0.89 86 1.9 1.7 1.6 0.89 87 4.9 4.8 4.5 0.98 88 1.9 1.7 1.7 0.89 89 1.8 1.6 1.6 0.89 90 1.9 1.6 1.7 0.84 91 4.5 4.5 4.5 1.00 92 3.8 3.6 3.4 0.95 93 3.8 3.7 3.6 0.97 94 1.9 1.6 1.6 0.84 95 4.4 4.3 4.3 0.98 96 4.6 4.5 4.1 0.98 97 1.8 1.7 1.6 0.94 98 4.3 4.2 4.1 0.98 99 4.9 4.8 4.5 0.98 100 4.1 4.0 4.1 0.98
119
APPENDIX B OYSTER, CLAM AND MUSSEL PICTURES
Figure B-1. Picture of oysters with dosimeter envelopes placed on them (6/8/05)
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Figure B-2. Picture of clams with dosimeter envelopes placed on them (6/8/05)
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Figure B-3. Picture of mussels with dosimeter envelopes placed on them (6/8/05)
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BIOGRAPHICAL SKETCH
Arthur Grant Hurst Jr., the older of Arthur and Darlene Hurst’s two children, was
born April 20, 1981, in Picayune, Mississippi. He graduated from Niceville High School
in 1999. He was awarded the Bachelor of Science degree from the University of Florida
in May, 2003, from the Department of Food Science and Human Nutrition. He continued
at the University of Florida for graduate study, in the Department of Food Science and
Human Nutrition, in pursuit of the Master of Science degree under the supervision of Dr.
Gary E. Rodrick. He was awarded the Master of Science degree in December of 2005.
Once graduated, Arthur plans to start a career working in the food industry specializing in
food safety and quality assurance.