Perfluorooctanoic acid

Perfluorooctanoic acid (PFOA), also known as C8, is an artificial acid that has many industrial uses. PFOA can designate the acid itself or its principal salts (like ammonium perfluorooctanoate, also known as APFO).

Perfluorooctane sulfonate is a related compound, used as a surfactant.

Uses
PFOA - pentadecafluorooctanoic acid is an industrial surfactant. One of the most common uses of PFOA is for processing polytetrafluoroethylene (PTFE), most widely recognized under the brand name Teflon by DuPont. PFOA, usually pronounced "P - F - O - A", is also a by-product of the telomerization process taking place on industrial scale in Asia, North America, and Europe by several international chemical companies. The telomerization process produces perfluorinated alcohol, which is commonly used in many household surface finishes and indirect contact applications in flexible food packaging. PFOA by-product is also in the fabrication of water- and stain-resistant clothes and other materials, including the products StainMaster, and Gore-Tex. (3M Scotchgard complied with a voluntary phase out of PFOS, a competing technology to the Zonyl trade name). PFOA by-product is also found in aqueous film forming foam (AFFF), a component of fire-fighting foams.

Fluorotelomer compounds (produced by several international companies) are used in food packaging to make them resistant to grease; however, these compounds may form PFOA when ingested. According to a USA Today article, these compounds have been used in "microwave popcorn bags, fast food and candy wrappers, and pizza box liners". In particular, microwave popcorn bags have the most fluorotelomers of any food wrapper, and the high cooking temperatures increase the migration of these chemicals into the popcorn oil. It is estimated that microwave popcorn may account for more than 20% of the average PFOA levels measured in American residents. Its elimination half-life is reported as being 4 years.

As discussed below with regard to health concerns, DuPont and 6 other companies have been asked to eliminate the use of PFOA completely by 2015.

Health concerns
The durability of PFOA prevents it from breaking down once in the environment, leading to widespread buildup and bioaccumulation in food chains. Traces of PFOA-family chemicals can now be found in the blood of nearly all Americans and in the environment worldwide. Scientists do not yet know how the chemicals are transported or exactly how dangerous they are to humans, although concerns about these issues caused its major manufacturer, 3M, to announce in May 2000 that it would cease producing the chemical. DuPont, one of the largest users of PFOA, then built its own plant in Fayetteville, North Carolina to manufacture PFOA.

DuPont has used PFOA for over 50 years at its Washington Works plant near Belpre, Ohio. Area residents sued DuPont in 2001, claiming the chemical contaminated area drinking water. As part of the settlement, DuPont is paying for blood tests and health surveys of residents believed to be affected. Up to 60,000 people are expected to take part in the study, which will be reviewed by epidemiologists to determine if there are any long-term health effects.

In 2004, DuPont came under investigation by the Environmental Protection Agency (EPA) for allegedly covering up knowledge of possible health effects of PFOA exposure in a study of pregnant employees, including evidence of PFOA in umbilical cord blood.

The EPA pursued charges against DuPont for failure to report violations filed under the Toxic Substances Control Act and the Resource Conservation and Recovery Act. On December 13, 2005 DuPont announced a settlement with the EPA in which DuPont will pay US$10.25 million in fines and an additional US$6.25 million for two supplemental environmental projects without any admission of liability.

Public watchdog groups are raising the alarm about PFOA. The Environmental Working Group says, in an online report titled "PFCs: A Family of Chemicals that Contaminate the Planet", that "PFCs seem destined to supplant DDT, PCBs, dioxin, and other chemicals as the most notorious, global chemical contaminants ever produced." As with most toxic chemicals, proving that PFOA is dangerous is very difficult and expensive. However it is up to the people who make these chemicals (which never before existed on earth) to prove they are safe before introduction so as to avoid another DDT mess. Moreover there are already serious concerns and a ban is being discussed.

On January 25, 2006, the EPA announced a long-term, voluntary program to reduce PFOA emissions and to eliminate PFOA use in products by the year 2015. While a New York Times article the next day claimed that companies would "stop using" PFOA, the EPA described its objective as "elimination of PFOA...from emissions and products" but not as a chemical intermediate to produce other substances.

On February 15, 2006, the EPA's Science Advisory Board voted to approve a recommendation that PFOA should be considered a likely carcinogen.

On November 21, 2006, EPA ordered DuPont company to offer alternative drinking water or treatment for public or private water users living near DuPont's Washington Works plant in West Virginia (and in Ohio), if the level of PFOA detected in drinking water is equal to or greater than 0.50 parts per billion (ppb). This greatly lowered action level replaced the previous 150 ppb threshold that was established in March 2002.

Recently, PFOA was found in German drinking water samples in concentrations of up to 0.60 µg/L.