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Anderson notes that DDT and DDE levels in nature have been falling for decades. Populations of bald eagles, peregrine falcons, ospreys, and brown pelicans have all bounced back. In 1969, researchers reported finding total DDT accumulations ranging from 5,000 ppm to 2,600 ppm in the fat of North American peregrine falcons. Today, one would typically find 50 ppm in raptors, according to Anderson. Such body burdens would yield only about 2.5 ppm in eggs. Anderson notes that there appears to be a threshold of one to three ppm for DDE in eggs below which there is no eggshell thinning in even sensitive bird species. Dusting DDT on the walls of houses in developing countries to control for mosquitoes seems unlikely to cross that threshold for birds.
In Silent Spring, Rachel Carson asked, "Who has decided—who has the right to decide—for the countless legions of people who were not consulted that the supreme value is a world without insects, even though it be also a sterile world ungraced by the curving wing of a bird in flight? The decision is that of the authoritarian temporarily entrusted with power."
Banning DDT saved thousands of raptors over the past 30 years, but outright bans and misguided fears about the pesticide cost the lives of millions of people who died of insect-borne diseases like malaria. The 500 million people who come down with malaria every year might well wonder what authoritarian made that decision.