The U.S. Food and Drug Administration (FDA) is “responsible for protecting the public health.” Or so says the first line of the agency’s mission statement.

As part of that mission, the agency has been positioning itself as taking a tougher stance with companies involved in the manufacturing and use of a harmful group of widely used industrial chemicals called per- and polyfluoroalkyl substances, short-handed as PFAS.

The substances are used to make products resistant to water, grease and stains along with an array of other applications.

The agency has been testing foods to determine what level of PFAS people may be exposed to in their daily diets; working with U.S. states to evaluate potential health threats from foods grown in places contaminated with PFAS; and reevaluating whether approved food contact substances (FCS) are allowing harmful levels of PFAS to migrate into food.

In January the FDA also proposed a new rule to change the process for how it can determine that these substances used in popular foods (think microwave popcorn bags) are no longer safe, and move to protect the public.