Glyphosate is an herbicide that’s widely used in agriculture in the U.S. and around the world. It’s the active ingredient in Roundup, which is commonly applied to crops like soy, cotton and corn that have been genetically modified to withstand the weed killer. The Environmental Protection Agency maintains that glyphosate is “not likely to be carcinogenic to humans,” although a ruling in 2022 by the United States Court of Appeals for the Ninth Circuit has prompted the agency to review the chemical’s risks to human health and the environment. 

A new study by economists at the University of Oregon examined how glyphosate may also be impacting the health of infants. It looked at millions of birth records from 1990 to 2013 to see if there were differences in birth weight and gestational length after Roundup use intensified in rural counties that grew genetically modified corn, soy and cotton compared to rural counties that weren’t suitable for growing those GM crops. It found that exposure to glyphosate was associated with lower birth weights and shorter gestations, with those effects being greater for some babies more than others. Joining us to talk about the findings is Ed Rubin, an assistant professor of economics at the University of Oregon.