The medical groups cite what they term “sufficiently robust” research showing associations between chemicals in our everyday environments and awful outcomes such as miscarriage, stillbirth, premature birth, childhood cancers, birth defects, and cognitive impairment in children. And they thus add their voices to those of other medical groups, including the American Academy of Pediatrics and the Endocrine Society, that have publicly called for stronger regulation.
The chemical industry, naturally, disagrees. The American Chemistry Council’s chief medical officer, Jayne Morgan, said in a statement that ACOG’s evidence on certain chemicals, such as BPA, is based on “a limited number of flawed studies.”
It’s true that there is no definitive evidence that certain chemicals among the 84,000 on record in the U.S. directly cause illness. ACOG’s president, Jeanne Conry, is clear about that. “We don’t have cause and effect,” she says. “But we have enough associations to make us concerned.”
Part of the challenge is that it’s ethically problematic to do the most rigorous studies, randomized controlled trials, for environmental health. You couldn't, say, deliberately expose Cleveland, but not Columbus, to an air pollutant for 10 years and then compare how the two populations fare. You can observe correlations between naturally occurring chemical exposures and human health, but these can take decades to become clear — by which time the harm may already be done. So, say the doctors groups, you have to rely on animal studies and other research in the lab.
The central question is how much evidence is enough when it comes to protecting our health. Science is always messy. It’s rarely possible to say that any given conclusion is unequivocally, 100 percent certain. So at what point on that murky spectrum do we decide to act? And, critically, who has the burden of proof?
At the moment, the burden is all on the U.S. government, yet the law gives it little power to intervene. The Toxic Substances Control Act was passed nearly 40 years ago and allows new chemicals to go essentially straight to market for use in everything from food packaging to nail polish — no systematic safety review required. Only if the Environmental Protection Agency independently demonstrates that a substance is dangerous can it request safety data from the company.
Thus, whereas pharmaceuticals go through rigorous, public study before they’re ever sold, “The exact opposite is true with chemicals. Chemicals are released into the environment and then they have to be studied,” says ACOG’s Conry.
Everyone — environmentalists, doctors, and even the American Chemistry Council — says the law is too weak and must be changed. But how much?
“Going back pretty far, the industry has basically won the day with the idea that chemicals should be treated as innocent until proven guilty,” says Gerald Markowitz, a health historian at City University of New York’s John Jay College.