RADIATION POISONING

A.A.Akhilesh

•Radiation is energy that travels in form of waves or high speed particles

•Radiation has a wide range of energies that span the electromagnetic spectrum

•There are two basic types of radiation 1.Non-Ionizing radiation : Light,radiowaves,Microwaves, and Radar. Does not cause any tissue damage 2.Ionizing radiation : Produces immediate chemical effects on human tissue. X-rays, Gamma rays, and particle bombardment (Neutron beam, Electron beam, Protons, Mesons)

• Radiation poisoning is the illness and symptoms resulting from excessive exposure to ionizing radiations

• In the body , Bone Marrow and the GI tract are especially sensitive to Radiation Injury

• Children and babies still in the womb are more likely to be severely injured

INTRODUCTION

Types of Radiation Exposure

Radiation exposure can be Due to a single large exposure (ACUTE) Due to series of small exposures spread over time (CHRONIC) Radaition exposure can also be Accidental Intentional (Radiation Therapy)

UNITS OF RADIATIONThe earliest used Units of measurement of Radiation are Curie and Becquerel •1 Becquerel is equal to one disintegration/second and 1 Becquerel corresponds to 27 Picocuries

The other units are Gray (Gy) and Sievert (Sv)

•Gray (Gy): It is a unit that expresses the energy absorbed by the target tissue per unit mass

•Sievert (Sv): It is a unit of equivalent dose that depends on biologic rather than physical effects of radiation

Potency of Radiation is measured in three ways•Roentgen : Roentgen is the unit of exposure. It is the amount of radiation absorbed in air at a given point

•Rad : Rad is the unit of absorbed dose. It is the amount of radioactive energy absorbed per gram of tissue or any material

•Rem : Rem is the product of the absorbed dose and the modifying factors. Rem indicates the degree of potential danger to health

ACUTE V/S CHRONIC EXPOSURE

ACUTE EXPOSURE

•Acute exposure is radiation exposure that occurs in a short period of time

•It can be an exposure that occurs once in lifetime (Eg: X-ray of foot for broken leg)

Acute exposures can also be exposures that occur more than once, but very infrequently and for short periods of time (Eg: Dental X-rays taken once in every few years)

Acute exposure can result in a small radiation dose ( Like an X-ray) or Large radiation dose that a person could receive in an accident situation

CHRONIC EXPOSURE•Chronic exposure is radiation exposure that occurs over a long period of time

•It can beContinuous exposure we receive daily from Natural background radiation ORRadiation exposure that occurs Off and On routinely over a long period of time in your lifeEg: Occupational Radiation Exposure Getting exposed to radiation at work almost daily over working lifetime

Chronic exposure can result in small or large radiation doses

SYMPTOMSFactors for the basis of symptoms are

Type and amount of radiation

Duration of exposure

The part of the body which was exposed

Signs and Symptoms usually appear when entire body receives an absorbed dose of atleast 1 Gy

Doses greater than 10 Gy to the whole body are generally not treatable and usually lead to death within 2 days-2 weeks

Initial Signs and symptoms of treatable radiation poisoning are Nausea and Vomiting

In general, Greater the radiation exposure, more severe the symptoms will be

The Chronic effects of Radiation poisoning generally include

•Life shortening•Carcinogenesis •Cataract formation•Chronic radiodermatitis •Decreased fertility•Genetic mutations