The health effects observed in the study population in West Virginia and Ohio are believed to have been caused by exposure to perfluorooctanoic acid, PFOA, also known as C8, released from the DuPont plant in Washington, West Virginia.
PFOA is one of a class of perfluorinated chemicals used to make Teflon coating and other nonstick products, oil-resistant paper packaging and stain-resistant fabrics.
A team from West Virginia University is leading the multi-year study of PFOA exposure. The study is funded by a portion of a $107.5 million settlement paid by DuPont to settle a 2005 lawsuit over releasing PFOA into the region's drinking water supplies.
Drops of oil on a pan coated with non-stick plastic made using PFOA. (Photo by Georgy Holden)
In earlier animal studies, PFOA exposure has been linked with death of immune cells and weakening of the body's ability to protect itself from infection.
Higher PFOA levels in West Virginia residents are associated with higher levels of two enzymes that can indicate liver damage, and with lower levels of a liver protein that is an important part of the body's defense against infection, the preliminary report finds.
Elevated PFOA levels in children are associated with high cholesterol levels, predisposing children to future weight problems and higher risk of heart disease.
Thyroid function was clearly affected in people exposed to PFOA, with the effect strongest at moderate levels of exposure, rather than the highest exposures, the researchers found.
"These findings may be preliminary, but they are very worrisome, because perfluorinated chemicals never break down," said Olga Naidenko, PhD, senior scientist at the nonprofit Environmental Working Group, which is campaigning to eliminate PFOA in the environment.
"Every molecule that is produced today will be around forever, continually cycling throughout the environment, food chain and people," said Naidenko.
There are no federal safety standards for perfluorinated chemicals in consumer products. DuPont and other manufacturers have pledged to phase out PFOA, but not until 2015.
In February, the U.S. Environmental Protection Agency said that eight major companies reported "significant drops in the release of PFOA and related chemicals, putting industry on target to meet a 95 percent reduction goal in PFOA emissions and product content by 2010." Further reductions are anticipated by 2015.
The eight companies are: Arkema, Asahi, Ciba, Clariant, Daikin, DuPont, 3M/Dyneon and Solvay Solexis.
In November 2007, the federal Centers for Disease Control and Prevention in Atlanta reported results from their analysis of human blood levels of PFOA collected in 2003-2004 and found a 25 percent reduction from levels found in samples collected in 1999-2000.
Dupont says products made with PFOA are "safe for their intended uses."
"Studies have shown very low levels of PFOA and other perfluorinated compounds in the environment and in the blood of the general population," Dupont acknowledges on its website. "Questions about this, as well as customer interest in product alternatives, are leading DuPont to phase out the use and production of PFOA by 2015 or earlier, if possible, and to develop new products and processes that are more environmentally sustainable," the company says.
Dupont points out that PFOA and Teflon are different - one is a processing aid, the other is a product brand. It is inaccurate to describe PFOA as an ingredient in cookware coated with Teflon, the company says. PFOA is a processing aid used to manufacture fluoropolymers, some of which are sold under the TeflonŽ brand.
The development of substitutes and alternates to PFOA is moving forward. To date, companies have submitted more than 50 chemical alternatives to the EPA for review.
In late 2006, Asahi introduced a new line of products that is PFOA free.
3M intends to introduce a PFOA substitute this year to be used in the manufacture of some of the products currently on the market.
3M Medical Director Larry Zobel, MD says, "In more than 25 years of medical surveillance we have observed no adverse health effects in our employees resulting from their exposure to ... PFOA. This is very important since the level of exposure in the general population is much lower than that of production employees who worked directly with these materials."
Nevertheless, some people do not want PFOA used to manufacture packaging for foods they wish to eat.
On Monday, the California State Senate approved legislation by San Leandro Democratic Senator Ellen Corbett to ban perfluorinated chemicals from food packaging.
"We're one step closer to getting these toxic chemicals out of food packaging," said Bill Walker, West Coast vice president of Environmental Working Group, which is sponsoring the legislation. "Alternatives are available now, so there's no reason to wait another seven years."
Copyright Environment News Service (ENS) 2008. All rights reserved.