The Biden administration is designating two “forever chemicals,” man-made compounds that are linked to serious health risks, as hazardous substances under the Superfund law, shifting responsibility for their cleanup to polluters from taxpayers.

The new rule announced on Friday empowers the government to force the many companies that manufacture or use perfluorooctanoic acid, also known as PFOA, and perfluorooctanesulfonic acid, known as PFOS, to monitor any releases into the environment and be responsible for cleaning them up.

The compounds, found in everything from dental floss to firefighting foams to children’s toys, are called forever chemicals because they degrade very slowly and can accumulate in the body and the environment. Exposure to PFAS has been associated with metabolic disorders, decreased fertility in women, developmental delays in children and increased risk of some prostate, kidney and testicular cancers, according to the Environmental Protection Agency.

The chemicals are so ubiquitous that they can be found in the blood of almost every person in the United States. In 2022, the E.P.A. found the chemicals could cause harm at levels “much lower than previously understood” and that almost no level of exposure was safe.

The pair of compounds are part of a larger family of chemical substances known collectively as PFAS.

The announcement follows an extraordinary move last week from the E.P.A. mandating that water utilities reduce the PFAS in drinking water to near-zero levels. The agency has also proposed to designate seven additional PFAS chemicals as hazardous substances.