The Environmental Protection Agency is setting a limit on the level of toxic cancer-causing chemicals allowed in drinking water. The agency will announce a plan Thursday to control a group of manmade chemicals known as PFAS—found in non-stick cookware and stain-resistant carpeting—which are linked to cancer as well as liver and thyroid damage. It’s not yet known what the specific permitted level for the toxic substances will be, but drinking water systems around the country will be tested for the chemicals to make sure they’re at lower levels than they were at a previous round of testing in 2012. It was previously reported by Politico that the EPA had no intention to limit the chemicals, which are believed to be contaminating millions of Americans’ tap water.