“A draft study of the risk posed by exposure to per- and polyfluoroalkyl substances, or PFAS, that was dubbed a ‘public relations nightmare’ by the White House shows new safety levels for the chemicals seven to ten times lower than current thresholds.
The new toxicological profiles released June 20 by the federal Agency for Toxic Substances and Disease Registry (ATSDR), comparatively drop the level at which no harm would be expected from exposure to people into the single digit parts-per-trillion (ppt) range.
According to environmental chemists, the proposed ATSDR ‘minimum risk levels’ or MRLs, translate roughly to 7-ppt for PFOS and 11-ppt for PFOA — the two PFAS compounds which the state of Michigan has established cleanup standards for groundwater that people drink.
The U.S. Environmental Protection Agency health advisory level for PFOS and PFOA is a combined 70-ppt, a level some researchers call inadequate to protect public health.
The ATSDR proposes MRLs translating to about 70-ppt for PFHxS and 10.5 ppt for PFNA, two PFAS compounds for which there are no federal standards. The compound PFHxS is closely associated with AFFF, a chemical-laden firefighting foam.
The ATSDR uses MRLs as a screening tool to assess whether exposures at a given contaminated site represent a potential health hazard. They are not enforceable regulatory standards.
‘This study confirms that the EPA’s guidelines for PFAS levels in drinking water woefully underestimate risks to human health,’ said Olga Naidenko, a senior science advisor at the nonprofit Environmental Working Group…
The EWG estimates tap water supplies for 110 million Americans are contaminated with PFAS chemicals, according it its own analysis…
The reports notes that available epidemiological studies suggest associations between PFAS exposure and several ailments in people:
* Pregnancy-induced hypertension/pre-eclampsia (PFOA, PFOS)
* Liver damage (PFOA, PFOS, PFHxS)
* Increases in total and LDL cholesterol (PFOA, PFOS, PFNA, PFDeA)
* Increased risk of thyroid disease (PFOA, PFOS)
* Decreased antibody response to vaccines (PFOA, PFOS, PFHxS, PFDeA)
* Increased risk of asthma diagnosis (PFOA)
* Increased risk of decreased fertility (PFOA, PFOS)
* Small decreases in birth weight (PFOA, PFOS)”
Read the full article by Garret Ellison