Rachel Carson was wrong about determining whether a substance will cause disease in the body by examining its effects on cells in test tubes and the belief that natural systems tend to evolve into a balanced state

See ‘Silent Spring & Other Writings’ Review: The Right and Wrong of Rachel Carson by Charles C. Mann. Excerpt:

"Carson’s claims about the direct risks pesticides and herbicides pose to human health do not stand up as well. Here again, she describes the science of the era accurately—problem is, the science in this area wasn’t especially good. Carson, like the researchers she reported on, thought we could accurately determine whether a substance will cause disease in the body by examining its effects on cells in test tubes. And she, like the cell biologists whose work she describes, thought we were much closer to understanding the workings of cancer than we actually were.

Today, five decades after “Silent Spring,” the relationship between agricultural chemicals and disease, especially cancer, remains frustratingly murky. To cite one example, we know that DDT in large doses—exposures of the sort that befall workers in pesticide-factory mishaps—is clearly bad news. But determining the effects of smaller doses—the type experienced by families whose lawns are sprayed—is much more difficult. By 2008, according to the U.S. Department of Health and Human Services’ “toxicological profile” for DDT and its derivatives, 15 peer-reviewed studies of various sorts had found a link between modest exposure to these pesticides and breast cancer. But another 40 had not found a link—and there was no obvious way to distinguish between the quality of the “yes” and “no” results.

Carson compounded the problem by combining her overconfidence with another then-prevalent ecological error, the belief that natural systems tend to evolve into a balanced state, a community of interconnected species that persists in perpetual equilibrium unless disturbed by humans. This idea of a balance of nature has ancient roots in the Great Chain of Being derived from Plato, as well as the Biblical vision of nature reflecting God’s perfection. In this view, ecosystems have a place and function for every creature and every species in them, and all work together as a kind of “superorganism.” When people wipe out species, they are, in effect, destroying the vital organs of this superorganism. They are heedlessly upsetting the balance of nature, which could bring down the whole ecosystem—a spiritual as well as ecological catastrophe.

Unfortunately, nature is not, in fact, in balance. Instead ecosystems are temporary, chaotic assemblages of species, with relations between them and their environment in constant flux. In 1990 ecologist Daniel Botkin wrote a classic book, “Discordant Harmonies,” to refute the stubborn belief in the balance of nature. (His polemic didn’t work: he wrote a follow-up book decrying the myth’s continued persistence in 2012.) As Mr. Botkin notes, the vision of nature as existing in eternal, faultless balance leaves humans only two roles: “to complete the perfection of nature or to interfere in its perfect processes.”

By embedding a justified critique of pesticide overuse in an intellectual framework that suggested cancer as the payback for tinkering with nature’s perfection, Carson inadvertently helped create an environmental movement that generally rules out the possibility of humans altering nature in ways that could be beneficial. The goal is always to re-create an idealized past state, not to work toward something new and beautiful. In an echo of the doctrine of original sin, the notion of humankind changing nature for the better is to be derided—how can one improve on perfection?"

See also We Were Winning the War Against Malaria: In the early 1970s malaria was all but eliminated by DDT.

"Regarding Novartis CEO Vas Narasimhan’s “How Long Till the Final World Malaria Day?” (op-ed, April 25): Dr. Narasimhan conveniently omits the fact that in the early 1970s malaria was all but eliminated by one of the most important pesticides ever invented—DDT. While study after study proved DDT to be effective in eliminating the malaria-carrying mosquito, the EPA’s first administrator, William Ruckelshaus, chose to ignore the opinions of his own study group and ruled against the continued use of DDT. The world followed and the exponential increase of malaria deaths followed around the world. Environmental groups cheered as the disease once again got out of control in the 1980s. Books like Rachel Carson’s flawed “Silent Spring” talked of thinning bird eggshells and increased bird mortality. Audubon bird-count records proved the opposite, and the eggshell studies were in fact of caged birds deprived of calcium in their diets.

Novartis surely will profit from continued efforts to control malaria through methods that will never equal what was already being accomplished by DDT. J. Gordon Edwards, who was the world’s leading expert on malaria and DDT in the 1970s, must be turning over in his grave."

Jay Lehr, Ph.D.
The Heartland Institute"