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The DDT Ban Controversy

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1 The DDT Ban Controversy
Dead Children vs. Dead Mosquitoes: The DDT Ban Controversy Yolanda Lukovinyova

2 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 The Nobel Prize was in Physiology and Medicine. After the war, DDT was heavily used as an agricultural insecticide.

3 DDT Chemical Information
Dichlorodiphenyltrichloroethane Molecular Formula C14H9Cl5 Molecular Weight 354.49 Melting point 108.5°C Boiling Point 260 °C Solubility (H2O) < 1 21 °C

4 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 The book Silent Spring scared the public about pesticides, specifically DDT, and rallied anti-chemical activists. In the book Rachel Carson described a wilderness area that was completely silent because of all the dead insects and diminishing bird populations.

5 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

6 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 The problem with DDT accumulation in fatty tissue is because of biomagnifiction. Biomagnification is the concentration effect that occurs through the food chain. For example, plankton acquire DDT and then it becomes magnified when a fish eats it, and so forth. The precautionary principle says that some technological activities pose such grave potential threats to our well-being that they should not be undertaken, even if definitive scientific evidence is not available to establish that the activity will cause the harm.

7 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 is very cheap thus it is the main way to control malaria and other such diseases in underdeveloped countries. Other options are not economically possible for such countries. No scientific study has ever been confirmed or replicated after the US ban proving a risk to human health and the environment.

8 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.

9 DDT is an insecticide Very effective towards disease carrying mosquitoes Used heavily after 1945 in the agriculture industry Cheapest insecticide available Insecticide is defined as any substance, either organic, inorganic, botanical, or microbial, that is used to destroy insects

10 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 During WWII, concentration camp survivors were drenched with DDT to kill the lice. There are no scientific reports describing adverse health effects after the DDT soaking.

11 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 The EPA (Environmental Protection Agency) considers a chemical carcinogenic if any benign tumor is formed. EPA regulations also say that a single positive test by one researcher takes precedence over the negative tests results of 100 researchers.

12 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 The researchers are now looking into PCBs and other chemicals as the culprit.

13 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

14 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 Judge Sweeney also said that the evidence in the proceeding supports the conclusion that there is a present need for the essential uses of DDT.

15 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.

16 Questions?

17 Sources Cited “Biomagnification: how DDT becomes concentrated as it passes through a food chain.” Biomagnification. June 13, ChemFinder. June 13, 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,

18 Sources Cited Cont’d Milloy, Steven. “At Risk from the Pesticide Myth.” Junkscience.com—At Risk from the Pesticide Myth. June 10, “Extoxnet Pesticide Information Profile—DDT.” EXTOXNET PIP – DDT. June 13, “Facts versus Fears: DDT”. Facts versus fears – DDT. June 13,

19 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, Many images are from Microsoft’s online clipart library. Mosquito. June 14, seth-swims.ohdrats.com/ sounds/ wav/ mosquito.wav Sound Aerosol Spray Can. June 14, kumori.free.fr/ aerosol.wav Virtual Zoo. June 12,


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