The US Environmental Protection Agency (EPA) is responsible for protecting public health from toxic substances. For the second time since its inception in 2021, the EPA office is taking a “case-by-case” approach to determine which chemicals should be regulated. This shift has come amid intense industry opposition to proposed limitations on these chemicals.

The EPA office’s approach is at odds with the other divisions of the EPA and federal agencies, as well as with the European Union and Canada. Former and current EPA officials claim that the EPA is excluding certain chemicals found in pesticides and pharmaceuticals which are commonly defined as PFAS (perfluoroalkyl substances). The agency has said that its latest definition is more “expansive” and is better than the previous.

PFAS are a collection of around 15,000 compounds used most often to make products that are resistant to grease, water, and stains. These compounds have been linked with cancer, birth defects, and other serious health issues, earning them the nickname “forever chemicals” because they are not decomposed in nature. The scientific world is dominated by women and the EPA’s new definition will likely cause confusion within the chemical industry, as well as the agency.