Unintended Consequences Don’t Undermine Science-Based Policy | Vol. 4 / No. 16.4

DDT Spraying in 1962 | Photo: Ken Hodge, CC BY 2.0

It’s been 65 years since Rachel Carson’s Silent Spring began the US environmental protection movement, and now that we’re talking about dismantling it entirely, I think it’s worth talking about this Daily Beast article. Even if outright banning DDT was wrong — and maybe it was — that’s no excuse for returning to an age of environmental ignorance.


Last week, the Daily Beast published an article titled “How Rachel Carson Cost Millions of People Their Lives.” The headline was clickbaity (as ever these days), and it should probably have read something more like “How Rachel Carson Was Part Of A Movement That Overreacted In Such A Way As To Lead To Potentially Millions of Unnecessary Deaths Worldwide Over The Last 60 Years,” but it’s longer, less pithy, and maybe too accurate for a headline these days.

The fact of the matter is that when the movement Carson started realized that we couldn’t just do whatever we liked without environmental consequence, it led to the potentially unfair demonization of a life-saving chemical: DDT. To be fair, DDT is a powerful and at times dangerous chemical. It can last in the environment for decades, and poisons birds so that their eggs have shells that are too thin to protect their young (which nearly wiped out the bald eagle, in fact). It’s toxic to a wide array of marine life, like crawfish and shrimp (which I don’t know about you, but I enjoy eating). It bioaccumulates, meaning that apex predators get all the DDT everything they ate ever ate, and all the DDT those things ate, too. There’s a lot of very good reasons to very heavily regulate the use of DDT.

But it’s not so dangerous to humans as Carson thought.

It can trick the body into thinking it’s estrogen, and in doing so can cause a host of issues, like preterm births in pregnant women and lower sperm counts in men, but then so can a lot of things we use in industrial applications but personally avoid putting into our bodies. The evidence for DDT causing cancer in humans is very limited, too.

And the benefits of preventing malaria are substantial.

As the Daily Beast article explains, “Probably no country benefited from DDT more than Nepal, where spraying began in 1960. At the time, more than two million Nepalese, mostly children, suffered from malaria. By 1968, the number was reduced to 2,500; and life expectancy increased from 28 to 42 years.

And the article is correct in its claims that death from malaria went way back up in many un- and underdeveloped countries after the DDT ban.

Does that make Rachel Carson responsible for millions of deaths? I would argue no.

Carson was in favour of following scientific research wherever it went, even if those places were uncomfortable. She read study after study to reach her conclusions, and it’s hard not to see how easy it was for the movement that she created — the “Pesticide Commission” became the Environmental Protection Agency after only a decade — became a reactionary. Nobody had ever thought we could have this much of an effect on the world. Some people still refuse to believe it (here’s looking at you, Climate Change deniers).

There may well be sensible ways we could (in certain areas of the globe) be applying DDT, based on community-driven, open processes that state the potential risks and rewards. An increased risk of early births and a potential risk of cancer might be better than a high risk of malaria. A limited application schedule might mitigate environmental impact. Like all things, policies on these matter should be informed, and based on an open debate that includes those whose lives are likely to be affected by the decisions made.

Rachel Carson said that it was not her contention “that chemical pesticides never be used,” and advocated for a science-based approach to policy. In a political climate where the outright dissolution of the EPA is being discussed, I think it’s more important than ever to remember that.

Science-based policy is not flawless, because science is sometimes wrong, but acting without science — acting in a knowledge vacuum so you can’t even begin to predict the environmental consequences — would be much, much worse.


Thanks for reading! Except for the very *very* occasional tip (we take Venmo now!), we only get paid in our own (and your) enthusiasm, so please like This Week In Tomorrow on Facebook, follow us on Twitter @TWITomorrow, and tell your friends about the site!


Richard Ford Burley is a human, writer, and doctoral candidate at Boston College, as well as Deputy Managing Editor at Ledger, the first academic journal devoted to Bitcoin and other cryptocurrencies. In his spare time he writes about science, skepticism, feminism, and futurism here at This Week In Tomorrow.