The governors of three US states have asked the federal Environmental Protection Agency (EPA) to help with additional drinking water testing and analysis in communities exposed to perfluorooctanoic acid (PFOA or C8), used by DuPont in the past as a polymerization aid in making its fluoropolymer Teflon.

The chemical has been linked to serious health problems including cancer, pregnancy complications and thyroid disease, and DuPont and its spin-off Chemours are currently embroiled in litigation with a number of plaintiffs who blame their health problems on PFOA.

Environmental health advocates in the states of Ohio and West Virginia are now questioning why officials in their states have been silent on possible contamination with the now-phased out chemical that belongs to a product group now part of Chemours.

Neither the federal nor state governments require public drinking water systems in Ohio or West Virginia to filter out the chemical, the advocacy groups say.

In 2005, EPA’s Ohio section sent letters to customers of the Little Hocking Water Association, advising residents that elevated levels of PFOA had been found in their water and noted that the agency would “continue its involvement in this issue.”

Addressing claims of inaction, a spokesman for the Ohio EPA told the newspaper Columbus Dispatch that Ohio follows federal guidelines on permitted levels of PFOA in water. These allow levels 95% higher than the levels recently set by Vermont, it said.

The Ohio EPA is said to be working on a lifetime health advisory level for the chemical, which is due to be presented in the near future.

For many years, DuPont stored PFOA-contaminated waste from its Washington Works plant in a landfill outside Parkersburg, West Virginia, and the chemical found its way into drinking supplies. In 2007, DuPont paid for water filters in four communities in southeastern Ohio.

Earlier this year, the chemical giant now preparing to merge with Dow Chemical and its spin-off were said to be facing some 5,300 US class action lawsuits related to the Teflon ingredient. In October 2015, a jury awarded $1.6 million to an Ohio woman who contracted kidney cancer and blamed it on PFOA. Four other trials are scheduled for 2016.

Without admitting guilt, Chemours accepted the October judgment, which did not call for punitive damages.

DuPont’s replacement for PFOA in 2013, a new polymerization aid known as GenX, is also under scrutiny as a possible water contaminant, but Chemours said extensive health safety testing has been conducted and the data has been shared with regulatory agencies around the world as well as published in peer-reviewed scientific publications. The full body of testing data indicates that the polymerization aid can be used safely in the manufacture of fluoropolymers, the company said.

According to Chemours, GenX has low acute toxicity in mammalian and aquatic testing, low repeated-dose toxicity in mammalian testing and is not a skin sensitizer. Data suggests that it is not a developmental, reproductive, or genetic toxicant, or a human carcinogen, it added.