Joseph G. Allen is assistant professor at Harvard T.H. Chan School of Public Health and faculty adviser to the Harvard Healthy Building Materials Academy.

Here’s a question: Do you think that a chemical cousin of nerve agents used in World War II that alters the brain function of children should be used as a pesticide? I’d hazard a guess that most people think this is a bad idea. The Trump administration, on the other hand, thinks this is just fine.

What I’m talking about here is the decision from President Trump’s Environmental Protection Agency — going against decades of science and its own scientist’s advice —to reject an Obama-era petition to ban the pesticide called chlorpyrifos.

What we know about chlorpyrifos is alarming. Perhaps the most well-known study is one done by researchers at Columbia University who performed brain imaging on young kids with high exposure to chlorpyrifos.