In July 2017, The New York Times ran a story titled The Chemicals in Your Mac and Cheese. Researchers, the article explained, had found plasticizers—known as phthalates—in the popular kids’ food. Fewer than two weeks later, the Times reported that traces of the herbicide glyphosate, the main ingredient in Roundup, had been found in Ben & Jerry’s ice cream. Several people asked me: Should we be worried?

My answer: Yes, we should, but not just because researchers found plasticizers (which are chemicals that make plastics more durable) in our mac and cheese or herbicide in our ice cream. We should be worried because these kinds of environmental chemical contaminants are literally everywhere, in nearly all our foods.

We know they exist in these two foods because researchers specifically looked for them. Roughly 9,000 environmental chemicals on the market end up in our foods, including food additives, colorings, flavorings, pesticides, and food-packaging chemicals. Even though they are ever-present in our environment and our bodies, many are never thoroughly tested for safety—and some are never tested at all.