This falls in the category of "something I wish I had written first". It's a brilliant takedown of a dead horse that conservatives just love to keep flogging - the myth that the environmentalist conspiracy to ban the pesticide DDT in 1972 led to a worldwide malaria epidemic that killed millions throughout the tropics.
I found this gem on Tim Lambert's Deltoid, over on Scienceblogs. Tim has been performing stout duty counteracting the waves of conservative crap about DDT. Jim Norton also provides a good primer on the conservative talking points about DDT here and here. Tim's most recent contribution is a link to this post on Jim Easter's blog, concerning EPA's regulatory decision-making of DDT use in agriculture. In 1972, the EPA cancelled agricultural uses of DDT (there's no such thing as "banning" a pesticide in US regulatory parlance). One of the talking points of the anti-environmentalist crowd is that EPA's regulatory action help gut malaria-control programs and led to the deaths of untold millions. As discussed below, the real history of DDT tells a different story.
Some backstory is necessary: DDT first started life as an insecticide during World War II, used for control of vector-borne diseases such as malaria and typhus. It was useful for this purpose because it provided effective insect control while also having low human toxicity. After the war, it became popular as an agricultural insecticide, and over the next 15 years, it's use in agriculture increased dramatically. However, after 1959, use of DDT declined steadily due to several factors including insect resistance, development of alternatives, growing public concern over adverse effects and increasing governmental regulation. The growing clamor over the hazards of DDT peaked with the publication of Silent Spring, in 1962. The public controversy continued over the relative benefits versus the risks from agricultural use of DDT. Four different government commissions reviewing DDT recommended phasing out its use. By this time (the early 1970s) the agricultural use of DDT had declined from a peak of 80 million pounds per year (in 1959) to 12 million pounds per year, with the bulk of the use on cotton. Throughout the late 1960s, the USDA (at the time, the agency responsible for pesticide registration) had been canceling the registrations for many uses of DDT. In 1971, pesticide regulatory authority was transferred to the new Environmental Protection Agency (EPA). In response to a court order, following a suit filed by the Environmental Defense Fund, the EPA began cancellation of all remaining uses of DDT in 1971. In June 1972, William Ruckelshaus, the EPA Administrator announced the final cancellation of all remaining agricultural uses of DDT. The order did not affect public health or quarantine uses or export of DDT. The cancellation was based on findings of persistence, transport, biomagnification, toxicological effects and the availability of effective and less environmentally harmful alternatives to DDT.
A claim made by the pro-DDT crowd (such as Steven Milloy at his DDT FAQi) is that Ruckekshaus disregarded the findings from his own hearing examiner in cancelling DDT, and that his decision was capricious and unsupported by the evidence. Easter has fact-checked this claim, including finding and posting the hard-to-find hearing examiner's record. He suggests that the pro-DDT case may be based on selective quoting of the hearing record - focusing on the findings where DDT wasn't a human and environmental health hazard, and ignoring those showing evidence of adverse effects, and provides examples where Ruckelshaus acknowledges the findings and clearly states his objections to them. One example is the famous eggshell thinning effect in birds. The pro-DDT crowd continues to assert there was enough doubt as to the presence of this effect such that restrictions on DDT use were unwarranted to protect wildlife. However, Easter observes that:
[f]or eggshell thinning, 35 years of research have shown that Ruckelshaus was right. A follow-up report issued in 1975 cited 179 studies related to eggshell thinning alone (pp. 69-81). Today, a quick check of PubMed for "ddt eggshell" turns up 50 papers since 1969, and it is clear from the abstracts that the association of thinning and DDT is well established. Bald eagle populations have rebounded since the DDT ban, so successfully that they are now delisted as threatened, a result accepted matter-of-factly by wildlife biologists as a benefit of the DDT ban (hyperlinks in the original).
Also ignored by the pro-DDT crowd is the fact that Ruckelshaus's decision carefully focused on US agricultural uses of DDT and not public health uses such as for control of mosquitos. Easter quotes from Ruckelshaus's order:
It should be emphasized that these hearings have never involved the use of DDT by other nations in their health control programs. As we said in our DDT Statement of March, 1971, "this Agency will not presume to regulate the felt necessities of other countries." (p. 26)
However, the phasing out of DDT use in cotton in the US spread to cotton growers around the world, with a positive benefit to public health pest control programs. As Easter says:
The 1972 DDT ban did nothing to restrict the chemical’s use against malaria, but had the effect of eliminating the single most intense source of selection pressure for insecticide resistance in mosquitos. As the rest of the world followed suit in restricting agricultural use of DDT, the spread of resistance was slowed dramatically or stopped.
By this single action, William Ruckelshaus — and, credit where it’s due, Rachel Carson — may well have saved millions of lives.
Steven Milloy is invited to add that to the DDT FAQ any time it’s convenient.
The braying of libertarian and conservative voices about millions being killed by denying the world DDT is clearly a distortion of the historical record which cynically uses the misery of tropical diseases such as malaria to flog their anti-environmentalist agenda.