By Kim Robson:
Is the EPA hiding reports on a class of chemicals known as perfluoroalkyls? They’re called PFAS, short for perfluoroalkyl substances, and the two most worrisome of this group are perfluorooctane sulfonates (PFOS) and perfluorooctanoic acid (PFOA).
EPA emails obtained under the Freedom of Information Act suggest that of PFOS and PFOA by the Agency for Toxic Substances and Disease Registry (ATSDR), a public agency with the Department of Health and Human Services, was squelched by the White House, calling it a “potential public-relations nightmare.” Apparently, the study said that the voluntary health advisory level of 70 parts per trillion (ppt) set by EPA in 2016 may still be far too high for sensitive people like infants and breast-feeding women.
PFAS are used in aqueous film forming foams (AFFF) for firefighting, particularly at military bases and commercial airports. Perfluorinated chemicals are used also in nonstick coatings and water-resistance treatments, in semiconductors and medical devices, and for protection of workers from hexavalent chromium carcinogens by forming a foamy film on top of metal plating baths. For many of these uses, there are .
PFOS and PFOA are “C8” chemicals (8 carbon atoms in a chain) and are highly resistant to environmental degradation. Longer-chained chemicals degrade only to a C8, at which point the breakdown ends. So, C8 PFAS can continue to build up in the environment even after all manufacturing of it has been banned.
For a long time, PFAS were considered nontoxic. Just watch this video of a test of firefighting foam, where at about 1:34, a worker wades right in with a sampling container:
Companies like 3M, the “principal worldwide manufacturer of PFOS and related chemicals” and DuPont, a major user of PFAS, have incurred multi-million-dollar penalties for not disclosing new information that suggested a substantial risk to exposure. The fallout led 3M to voluntarily phase out production of PFOS.
Other countries have followed suit. The Stockholm convention on persistent organic pollutants (POPs) in 2009 called for the restricted use of PFAS; however, PFOA and related chemicals are not yet designated as POPs at the global convention level. In the European Union, PFOS and PFOA also are banned with exceptions for difficult-to-substitute uses until these can be phased out. In the U.S., the EPA has restricted hundreds of perfluoroalkyl chemicals, banning any new uses without their specific approval, and established cooperative efforts with industry to phase out all use of PFOA and longer chemicals that break down to PFO, by 2015. All of the major leading industry companies invited to join the effort have met the goals of the program.
What are the dangers of PFOS and PFOA and how many people are exposed to them? Developmental damage, cancer, liver and other organ damage, immune system effects, thyroid hormone disruption, and cardiovascular concerns have been cited. The ATSDR’s “” states that “PFOA, PFOS, PFNA, and PFHxS were detected in 95–100% of samples of people’s blood in 1999–2000 and 2003–2004.” Luckily, more recent monitoring shows that these levels are decreasing, probably due to recent phase-outs. Of course, workers exposed to PFAS have much higher levels of these chemicals in their blood than the normal population has. We should be monitoring their health as a sort of “canary in the coal mine” program.
The bottom line is thatC8 PFAS don’t degrade in the environment and can cause exposures for a very long time, and we should minimize exposure to it as much as possible until more studies on their health effects are published. Alerting the public to a potential health threat should never be squelched because it might be considered a “public-relations nightmare.”