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PFOA, PFOS and Other PFASs

GenX Chemicals Studies

To aid states, local communities or other interested parties in analysis or management of issues related to GenX chemicals in their jurisdictions, EPA is providing all health-related studies (GenX acid and GenX ammonium salt) conducted and submitted by DuPont/Chemours in the Health and Environmental Research Online database. In addition, EPA recently conducted a comprehensive search of the open literature to identify additional scientific articles with health related information about GenX chemicals.


GenX is a trade name for a processing aid technology developed by DuPont (now Chemours). In 2008, EPA received new chemical notices under the Toxic Substance Control Act from DuPont (which is now Chemours) for two chemical substances that are part of the GenX process (Hexafluoropropylene oxide (HFPO) dimer acid and the ammonium salt of HFPO dimer acid).

In 2009, EPA and the company signed a Consent Order for the substances which required health and environmental testing, and also controlled worker exposures, environmental releases and the amount of impurities permissible in the final polymers. The testing required by the Consent Order included pharmacokinetics testing, reproductive testing, and carcinogenicity testing in animals. Ecotoxicity testing included chronic testing in aquatic organisms and an avian reproductive study.

EPA typically requires testing for new perfluorinated chemicals to determine whether the toxicity, fate and bioaccumulation issues that have caused past concerns with perfluorinated substances may be present and to ensure that new chemicals do not present an unreasonable risk to health or the environment. Dupont/Chemours conducted the required testing and provide it to EPA. The Agency is currently analyzing the data it has received under the Consent Order.