From Sludge to food
PFOA can form as a breakdown product from a variety of precursor molecules. PFOA precursors can be transformed to PFOA by metabolism, biodegradation, or atmospheric processes. The OECD identified 615 chemicals that potentially break down to form PFCA. However, not all of these chemicals have the potential to break down to form PFOA. A majority of waste water treatment plants (WWTPs) that have been tested output more PFOA than is input, and this increased output has been attributed to the biodegradation of fluorotelomer alcohols.
PFOA and PFOS were detected in "very high" (low parts per million) levels in agricultural fields for grazing beef cattle around Decatur, AL. The approximately 5000 acres of land were fertilized with "treated municipal sewage sludge, or biosolids." PFOA was also detected in the blood of the cattle. The water treatment plant received process wastewater from a nearby perfluorochemical manufacturing plant. 3M says they managed their own wastes, but Daikin America "discharged process wastewater to the municipal waste treatment plant." If traced to meat, it would be the first time perfluorochemicals were traced from sludge to food.
On February 15, 2005, the USEPA's Science Advisory Board (SAB) voted to recommended that PFOA should be considered a "likely human carcinogen."
On May 26, 2006, the USEPA's SAB addressed a letter to Stephen L. Johnson. Three-quarters of advisers thought the stronger "likely to be carcinogenic" descriptor was warranted, in opposition to the USEPA's own PFOA hazard descriptor of "suggestive evidence of carcinogenicity, but not sufficient to assess human carcinogenic potential."
Evidence of Harm versus Industry Denial and Coverup
After decades of evidence of harm from these chemicals, in 2006 the U.S. Environmental Protection Agency (EPA) finally had commitments from eight manufacturers of PFOA to voluntarily reduce emissions and product content of PFOA and related chemicals in the United States and overseas by 95 percent by 2010, and to work toward eliminating emissions and product content of these chemicals by 2015. This action was brought on because the chemical was associated with "systemic and developmental toxicity."
Facial birth defects, an effect observed in rat offspring, occurred with the children of two out of seven female DuPont employees from the Washington Works facility from 1979-1981; however, DuPont does not accept any responsibility from the toxicity of PFOA. With other highly exposed populations, a 2000 3M epidemiology study recorded statistically significant increases in cholesterol, triglyceride, and triiodothyronine levels and a statistically significant decrease in HDL with increasing levels of PFOA. A 3M funded study found workers who were highly exposed to PFOA had twice the odds of dying from prostate cancer and stroke when compared to other workers at the same plant.
In response, 3M's spokesman said, "nothing in this study changes our conclusion that there are no adverse health effects from PFOA."
A DuPont report on the rate of occurrence of carcinoid tumors at their Washington, WV plant gave "preliminary evidence for a cancer cluster." DuPont responded by stating that they did not have any reason to believe the increase from the Washington Works plant was due to any specific chemical. In a May 2008 preliminary report released by West Virginia University (WVU), PFOA was linked to liver, thyroid, immune system, and cholesterol changes considered harmful in the population around DuPont's Washington, WV plant. In a quick response to the release of the WVU report, DuPont's spokesman highlighted the preliminary nature and the legal issue of the industry dominated C8 Science Panel being the only court appointed authority on study results. The C8 Science Panel also criticized the WVU release, labeling the graphs as "simple" that related PFOA to several blood tests because they did not represent a thorough data analysis. In October 2008, when the C8 Science Panel released findings, PFOA was only linked to high levels of cholesterol.
Despite DuPont asserting that "cookware coated with DuPont Teflon non-stick coatings does not contain PFOA," residual PFOA was also detected in finished PTFE products including PTFE/Teflon cookware. Additionally, a New York State Department of Health study detected PFOA in the gas phase coming from new nonstick cookware and microwave popcorn bags in research funded by a 2005-2006 $17,700 grant from the Consumers Union.
In the face of all the evidence of PFOA harm to humans, DuPont's position continues to be that the data does not prove PFOA causes health effects.