|
|Section2= |Section3= |Section7= |Section8= }} Perfluorooctanoic acid (PFOA), also known as C8 and perfluorooctanoate, is a synthetic perfluorinated 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 (PTFE). In 2013, Gore-Tex eliminated the use of PFOAs in the manufacture of its weatherproof functional fabrics.〔(【引用サイトリンク】title=GORE completes elimination of PFOA from raw material of its functional fabrics : GORE-TEX Products Newsroom )〕 PFOA has been manufactured since the 1940s in industrial quantities.〔http://www.epa.gov/fedfac/pdf/ec_technical_fs_pfos_pfoa_march_2013.pdf〕 It is also formed by the degradation of precursors such as some fluorotelomers. 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. As a result of a class-action lawsuit and community settlement with DuPont, three epidemiologists conducted studies on the population surrounding a chemical plant that was exposed to PFOA at levels greater than in the general population. The studies concluded that there was probably an association between PFOA exposure and six health outcomes: kidney cancer, testicular cancer, ulcerative colitis, thyroid disease, hypercholesterolemia (high cholesterol), and pregnancy-induced hypertension. ==History== In 1947, 3M began producing PFOA by electrochemical fluorination.〔 In 1951, DuPont started using PFOA in the manufacturing of fluoropolymers in Washington, WV. In 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. In the 1980s and 1990s researchers investigated the toxicity of PFOA.〔 In 1999, the United States Environmental Protection Agency (USEPA) began investigating perfluorinated chemicals after receiving data on the global distribution and toxicity of PFOS. For these reasons, and USEPA pressure, in May 2000, 3M announced the phaseout of the production of PFOA, PFOS, and PFOS-related products.〔(【引用サイトリンク】 title =3M United States: PFOS PFOA: What is 3M Doing? )〕 3M stated that they would have made the same decision regardless of USEPA pressure. Because of the 3M phaseout, 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.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Perfluorooctanoic acid」の詳細全文を読む スポンサード リンク
|