PFOA & PFOS
WHAT ARE PFOA & PFOS?
PFC is the name given to the broad family of products called per-fluorinated compounds. PFOS and PFOA (C8) belong to that family. PFOS and PFOA are therefore both PFCs. The difference between family members is primarily determined by how many carbon atoms are in the per-fluorinated chain. PFOS and PFOA are both Octyl -- that is -- they both have eight (8) carbons.
Perfluorooctanoic acid (PFOA) (conjugate base perfluorooctanoate), also known as C8, is a synthetic per-fluorinated carboxylic acid and fluorosurfactant. One industrial application is as a surfactant in the emulsion polymerization of fluoropolymers. It has been used in the manufacture of such prominent consumer goods as polytetrafluoroethylene (commercially known as Teflon).
PFOA has been manufactured since the 1940s in industrial quantities. It is also formed by the degradation of precursors such as some fluorotelomers. The primary manufacturer of PFOS – 3M (known as Minnesota Mining and Manufacturing Company from 1902 to 2002) – began a production phase-out in 2002 in response to concerns by the United States Environmental Protection Agency and eight other companies agreed to gradually phase them out by 2015
PFOA persists indefinitely in the environment. It is a toxicant and carcinogen in animals. PFOA has been detected in the blood of more than 98% of the general US population in the low and sub-parts per billion range, and levels are higher in chemical plant employees and surrounding subpopulations. How general populations are exposed to PFOA is not completely understood. PFOA has been detected in industrial waste, stain resistant carpets, carpet cleaning liquids, house dust, microwave popcorn bags, water, food, some cookware and PTFE such as Teflon.
WHAT ARE PFOA & PFOS USED FOR?
3M (then Minnesota Mining and Manufacturing Company) began producing PFOA by electrochemical fluorination in 1947. Starting in 1951, DuPont purchased PFOA from 3M for use in the manufacturing of specific fluoropolymers—commercially branded as Teflon, but DuPont internally referred to the material as C8.
In the fall of 2000, lawyer Rob Bilott, a partner at Taft Stettinius & Hollister, won a court order forcing DuPont to share all documentation related to PFOA. This included 110,000 files, consisting of confidential studies and reports conducted by DuPont scientists over decades. By 1993, DuPont understood that "PFOA caused cancerous testicular, pancreatic and liver tumors in lab animals" and the company began to investigate alternatives. However, products manufactured with PFOA were such an integral part of DuPont's earnings, $1 billion in annual profit, they chose to continue using PFOA. Billott learned that both "3M and DuPont had been conducting secret medical studies on PFOA for more than four decades", and by 1961 DuPont was aware of hepatomegaly in mice fed with PFOA.
In 1968, organofluorine content was detected in the blood serum of consumers, and in 1976 it was suggested to be PFOA or a related compound such as PFOS. Rob Bilott exposed how DuPont had been knowingly polluting water with PFOAs in Parkersburg, West Virginia since the 1980s. In the 1980s and 1990s researchers investigated the toxicity of PFOA.
In 1999, the United States Environmental Protection Agency (USEPA) ordered companies to examine the effects of per-fluorinated chemicals after receiving data on the global distribution and toxicity of PFOS. For these reasons, and USEPA pressure, in May 2000, 3M announced the phase out of the production of PFOA, PFOS, and PFOS-related products—the company's best-selling repellent. 3M stated that they would have made the same decision regardless of USEPA pressure.
Because of the 3M phase out, in 2002 DuPont built its own plant in Fayetteville, NC to manufacture the chemical. The chemical has received attention due to litigation from the PFOA-contaminated community around DuPont's Washington Works Washington, WV facility, along with USEPA focus. Research on PFOA has demonstrated ubiquity, animal-based toxicity, and some associations with human health parameters and potential health effects. Additionally, advances in analytical chemistry in recent years have allowed the routine detection of low- and sub-parts per billion levels of PFOA in a variety of substances. In 2013, Gore-Tex eliminated the use of PFOAs in the manufacture of its weatherproof functional fabrics.
After Months of Anger in Hoosick Falls, Hearings on Tainted Water Begin (Aug 30, 2016, NY Times)
Public Hearings for Hoosick Falls and Petersburgh PFOA Contamination (change.org)
LONG-TERM HEALTH EFFECTS
PFOA and PFOS (C8) have been shown to be extremely persistent chemicals, both in the environment and in human tissue. A recent study has linked these chemicals to serious damage to the immune system in children (Grandjean et al, 2012). But PFOA and PFOS are just two of a family of fluorochemicals called PFCs, which in turn are part of the fluorocarbon family. During 2005 to 2013, the C8 (PFOA) Science Panel carried out exposure and health studies by collecting data from 69,000 people. These people lived in the Mid-Ohio Valley communities and were exposed to PFOA. They published their findings in “Probable Link Reports.” Here are the health ailments with a probable link to PFOA exposure:
- Diagnosed high cholesterol
- Ulcerative colitis
- Thyroid disease
- Pregnancy-induced hypertension
- Kidney cancer
- Testicular cancer
The EPA affirms those findings and adds:
- Developmental effects for fetuses
- Liver tissue damage
- Immune system impairments to the list
- Damage to immune system in children leading to an inability to respond to inoculations for tetanus and diphtheria (Grandjean et al, 2012).
- Increased incidence of cancer associated with PFC pollution (Bonefeld-Jorgensen et al, 2011)
- Compromised female fertility associated with PFC blood levels in women – delayed time to conception (Fei et al, 2009)
Enlarged livers associated with PFC
Low birth weight associated with PFC
Reduced fertility associated with PFC
DuPont Settles Big Teflon Case, But PFOA Pollution Lingers Nationwide (Environmental Working Group)
- State: Bennington Residents Who Consumed Water With PFOA Have It In Their Blood (Vermont Public Radio)
- Vermont Sets A Permanent Drinking Water Standard For PFOA (Vermont Public Radio)
- Under Dupont Bridge: The Teflon Toxin Goes To China (The Intercept)