Download - The DDT Ban Controversy
The DDT Ban Controversy
Yolanda Lukovinyova
What is DDT Anyway?
• Organochlorine insecticide • First synthesized in 1877• 1948 Dr. Paul Müller was awarded
the Nobel Prize for its insecticide properties
• Extensively used during WWII to control typhus and malaria
• Banned in the US in 1972
DDT Chemical Information
DDT DichlorodiphenyltrichloroethaneMolecular
FormulaC14H9Cl5
Molecular Weight
354.49
Melting point 108.5°C
Boiling Point 260 °C
Solubility (H2O) < 1 mg/mL @ 21 °C
Why did the US ban DDT?
• The public outcry based on the book, Silent Spring by Rachel Carson published in 1962
• Scientific studies showed that DDT was carcinogenic
• Scientific studies showed that DDT caused thinning egg shells in birds
• Toxicity data acquired about DDT
Worldwide Ban Controversy
• UN had to decide if a worldwide ban by 2004 should be implemented
• The ban was to be imposed on 12 toxic chemicals known as the Dirty Dozen.
• DDT is part of the Dirty Dozen
Worldwide Ban Cont’d
• Proponents evidence:– Scientific studies done to show DDT is
carcinogenic– Scientific studies showing egg shell thinning
in various bird populations as a result of DDT
– DDT is so stable it takes many years to decompose
– DDT accumulates in fatty tissue of animals– Precautionary principle
Worldwide Ban Cont’d
• Opponents evidence:– Banning DDT would kill millions of people
because it helps control malaria, typhus and other diseases
– Many of the scientific studies were flawed– No human has ever died from DDT– Bans should not be based on
precautionary principles, rather on science
DDT should not be banned because…
• Prevents diseases • Good insecticide• Science proving DDT to be
carcinogenic and bad for the environment is flawed
• Politics controlled the US decision to ban DDT, not factual science.
DDT is an insecticide
• Very effective towards disease carrying mosquitoes
• Used heavily after 1945 in the agriculture industryCheapest
insecticide available
Cheapest insecticide available
DDT prevents diseases
• Can be used to kill disease-bearing lice
• DDT can be used as a repellant– Sprayed on walls of buildings to repel
insects– Diseases insects can carry are
malaria, sleeping sickness, and yellow fever
DDT flawed science
• Carcinogenic studies– In 1969 study of mice, it was shown
that the DDT sprayed mice developed tumors.
– Reality was that the mice food was carcinogenic
– After the study was redone without carcinogenic food, no mouse formed a tumor
DDT flawed science cont’d
• Eggshell thinning evidence– 1968 studies reported high DDT
concentrations in the eggs of raptors•Resulting in thinning egg shells•Decline in population
– Reality was that the population declined before the use of DDT and after it had been banned
– Researchers admitted to the fact that the egg extracts studied had little or no DDT
DDT Flawed Science Cont’d
• Another study, done with quails showed a thinning egg shell problem– Quail diet in the study did not have
enough calcium – If there is not enough calcium in the
diet, egg shells naturally thin
DDT and Politics
• US ban was based on politics• 1972, Judge Sweeney listened to 7
months of testimony about DDT and determined it not to be a carcinogenic hazard to man or animals
• 2 months later, EPA head declared that DDT was a potential human carcinogen and should be banned
Conclusion
• DDT should not be banned worldwide because of the lack of scientific evidence.
• Not allowing the use of DDT would kill millions of people around the world
• I prefer dead mosquitoes over dead children.
Sources Cited
• “Biomagnification: how DDT becomes concentrated as it passes through a food chain.” Biomagnification. June 13, 2002. http://www.ultranet.com/~jkimball/BiologyPages/D/DDTandTrophicLevels.html
• ChemFinder. June 13, 2002. http://www.chemfinder.com
• Dinan, Frank J. and Bieron, Joseph F. “To Spray or Not to Spray: A Debate Over Malaria and DDT.” To Spray or Not to Spray: A Debate Over Malaria and DDT- Case Study Collection. June 13, 2002. http://ublib.buffalo.edu/libraries/projects/cases/ddt/ddt.htm
Sources Cited Cont’d
• Milloy, Steven. “At Risk from the Pesticide Myth.” Junkscience.com—At Risk from the Pesticide Myth. June 10, 2002. http://www.junkscience.com/foxnews/fn072800.htm
• “Extoxnet Pesticide Information Profile—DDT.” EXTOXNET PIP – DDT. June 13, 2002. http://ace.orst.edu/cgi-bin/mfs/01/pips/ddt.htm
• “Facts versus Fears: DDT”. Facts versus fears – DDT. June 13, 2002. http://www.altgreen.com.au/chemicals/ddt.html
Sources Cited Cont’d
• Katz, Harry. “DDT and Chlordane Killed by Politics, Not Science.” PCT Online >> Article >> DDT and Chlordane Killed by Politics, Not Science. June 13, 2002. http://www.pctonline.com/articles/article.asp?Id=216&SubCatID=36&CatID=9
• Many images are from Microsoft’s online clipart library.
• Mosquito. June 14, 2002. seth-swims.ohdrats.com/ sounds/ wav/ mosquito.wav
• Sound Aerosol Spray Can. June 14, 2002. kumori.free.fr/ aerosol.wav
• Virtual Zoo. June 12, 2002. http://students.cs.byu.edu/~ik7/virtualzoo/