Biology Decision Case Bi o m a g n i f i cati on.
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Transcript of Biology Decision Case Bi o m a g n i f i cati on.
The Problem:The Problem:
Peregrine Peregrine FalconsFalcons
ExtirpatedExtirpated
from much of from much of U.S.U.S.
http://www.iowaccess.org/main/news/newsimages/peregrine.jpg
Osprey andOsprey andBald Eagles Bald Eagles were were declining,declining,as well.as well.
http://www.state.tn.us/twra/graphics/OSPREY.jpghttp://www.state.tn.us/twra/graphics/OSPREY.jpg
http://www.state.tn.us/twra/graphics/BLDEAGLE.jpghttp://www.state.tn.us/twra/graphics/BLDEAGLE.jpg
Meanwhile, in Borneo:Meanwhile, in Borneo: Roofs began to fallRoofs began to fall Gecko-eating cats Gecko-eating cats
began to die,began to die, and thriving rats and thriving rats
brought plague and brought plague and typhustyphus
The World Health The World Health Organization began to Organization began to parachute cats into parachute cats into Borneo, but what was Borneo, but what was causing these causing these problems?problems?
http://www.herpafauna.com/pics/geckos/a-felinus.jpg
Finding the cause:Finding the cause:Roof collapse Roof collapse
traced to traced to disappearance disappearance of parasitic of parasitic wasp which wasp which had controlled had controlled thatch-eating thatch-eating caterpillars.caterpillars.
http://www.life.umd.edu/classroom/bsci124/img/parisitoid.jpg
It seemed to be a chain:It seemed to be a chain:
Wasps disappeared Wasps disappeared because DDT had because DDT had been sprayed to kill been sprayed to kill mosquitos, which mosquitos, which carried malaria - carried malaria - number one killer of number one killer of humans worldwidehumans worldwide
The data suggested DDT:The data suggested DDT:
Measurements of DDT levels seemed to Measurements of DDT levels seemed to multiply as the compound moved up the multiply as the compound moved up the food chain:food chain:
• Water to zooplankton: 800x Water to zooplankton: 800x • Zooplankton to fish #1 = 31x Zooplankton to fish #1 = 31x • Fish #1 to fish #2 = 1.7x Fish #1 to fish #2 = 1.7x • Fish #2 to gull = 4.8x Fish #2 to gull = 4.8x • Overall = 202,368xOverall = 202,368x
More evidence against DDT:More evidence against DDT:
Eggshells Eggshells from from Peregrines Peregrines with high with high DDT levels DDT levels showed showed significant significant thinningthinning
http://www.kodak.com/US/images/en/corp/features/birdcam2000/gallery/04_03/13_32__2000_04_03_fullcam2.jpg
How does biomagnification work?How does biomagnification work?
DDT, a synthetic DDT, a synthetic molecule, cannot be molecule, cannot be broken down or broken down or excreted – Life excreted – Life doesn't have doesn't have enzymes that enzymes that "know" how."know" how.
Thus, it Thus, it concentrates as concentrates as animals higher on animals higher on the food chain eat the food chain eat more and more more and more food.food.
Solutions:Solutions:
Ban DDTBan DDT
"Hack out" captive-bred"Hack out" captive-bred
peregrine chicksperegrine chicks
Build nest platforms for OspreyBuild nest platforms for Osprey
How effective were these How effective were these solutions?solutions?
Peregrines, Osprey, and Bald Eagles Peregrines, Osprey, and Bald Eagles recoveredrecovered
However,However, Other countries still use DDTOther countries still use DDT
andand DDT isn't the only chemical that DDT isn't the only chemical that
biomagnifies!biomagnifies!
The problem magnifies:The problem magnifies:
MethylMercury MethylMercury concentrates just like concentrates just like DDT and damages DDT and damages humanhuman
Nervous SystemsNervous Systems A person who eats one A person who eats one
meal of lake trout from meal of lake trout from Lake Michigan will be Lake Michigan will be exposed to more exposed to more
PCBsPCBs in one meal in one meal than in a lifetime of than in a lifetime of drinking water from the drinking water from the lake!lake!
The Problem is ongoing:The Problem is ongoing:
PCBs (polychlorinated PCBs (polychlorinated biphenyls) biphenyls)
PAHs (polynuclear aromatic PAHs (polynuclear aromatic hydrocarbons) hydrocarbons)
Heavy metals: Heavy metals: • mercury mercury • copper copper • cadmium cadmium • chromium chromium • lead lead • nickel nickel • zinc zinc • tintin
TBT (tributyltin) TBT (tributyltin) mercury from gold mining mercury from gold mining cyanide cyanide selenium selenium
The number of The number of new molecules new molecules we introduce we introduce into our into our environment environment continues to continues to increase.increase.
The Ultimate Solution?The Ultimate Solution?
Models are being developed to predict Models are being developed to predict toxicity of new chemicalstoxicity of new chemicals
Pollution control must be intensified:Pollution control must be intensified:
Zero Tolerance in the Great Lakes?Zero Tolerance in the Great Lakes?
Education: Increase awareness soEducation: Increase awareness so
everyone will decrease use and dispose everyone will decrease use and dispose of chemicals properly.of chemicals properly.
"This we know: The earth does not "This we know: The earth does not belong to man; man belongs to the belong to man; man belongs to the earth. Whatever befalls the earth earth. Whatever befalls the earth befalls the sons of the earth. Man did befalls the sons of the earth. Man did not weave the web of life; he is not weave the web of life; he is merely a strand in it. Whatever he merely a strand in it. Whatever he does to the web he does to himself."does to the web he does to himself."
- Chief Seattle - Chief Seattle
Bibliography…Bibliography… "ToxFAQsTM for DDT, DDE, and DDD," ATSDRIC Information Center Division of "ToxFAQsTM for DDT, DDE, and DDD," ATSDRIC Information Center Division of
Toxicology, Agency for Toxic Substances and Disease Registry, Atlanta, GA, Toxicology, Agency for Toxic Substances and Disease Registry, Atlanta, GA, June 11, 2001. <http://www.atsdr.cdc.gov/tfacts35.html> 2/21/02June 11, 2001. <http://www.atsdr.cdc.gov/tfacts35.html> 2/21/02
Mader, Sylvia S. 1996. Mader, Sylvia S. 1996. Biology Biology - 5th Ed. WCB and Cox, G.W. 1997. - 5th Ed. WCB and Cox, G.W. 1997. Conservation BiologyConservation Biology - 2nd ed. WCB < - 2nd ed. WCB < http://www.marietta.edu/~biol/102/2bioma95.html> 2/21/02http://www.marietta.edu/~biol/102/2bioma95.html> 2/21/02
"Chapter 4: The Great Lakes Today – Concerns" Government of Canada "Chapter 4: The Great Lakes Today – Concerns" Government of Canada (Toronto, Ontario) (Toronto, Ontario) and and United States Environmental Protection Agency, Great United States Environmental Protection Agency, Great Lakes National Program Office (Chicago, Illinois) The Great Lakes: An Lakes National Program Office (Chicago, Illinois) The Great Lakes: An Environmental Atlas and Resource Book, Third Edition, 1994, Environmental Atlas and Resource Book, Third Edition, 1994, http://www.epa.gov/glnpo/atlas/glat-ch4.html> 2/20/02http://www.epa.gov/glnpo/atlas/glat-ch4.html> 2/20/02
"Mercury: In Your Community and the Environment." PUB-CE-239 98 "Mercury: In Your Community and the Environment." PUB-CE-239 98 Wisconsin Department of Natural Resources and the Pollution Prevention Wisconsin Department of Natural Resources and the Pollution Prevention Partnership; Last Modified: November 29, 1999 Environment Canada : Partnership; Last Modified: November 29, 1999 Environment Canada : http://www.on.ec.gc.ca/glimr/classroom/millennium/mercury/mystery-e.htmlhttp://www.on.ec.gc.ca/glimr/classroom/millennium/mercury/mystery-e.html
"Great Lakes Initiatie," Wisconsin Sea Grant, 2001"Great Lakes Initiatie," Wisconsin Sea Grant, 2001
http://seagrant.wisc.edu/Communications/Publications/One-pagers/http://seagrant.wisc.edu/Communications/Publications/One-pagers/CriticalPollutants.html 2/20/02CriticalPollutants.html 2/20/02