July 6, 2005
What is the Risk?
Government tries to solve C8 puzzle
By Callie Lyons
While there is still no definitive answer to the question, Is C8 a health risk to humans? two federal agencies are trying to put together pieces of the puzzle.
Last week, the Environmental Protection Agencys Science Advisory Board, a panel of independent scientists, released their draft report on PFOA also known as PFOA or perfluorooctanoic acid - with a warning that they believe the substance is more harmful than initially suspected, calling it a likely human carcinogen.
Preliminary results of a Food and Drug Administration study shared with an audience in Barcelona, Spain reveal that the controversial manmade chemical is potentially being served up to millions of unaware consumers daily - not through plant emissions or landfill pollution - but as a common ingredient in popular food packaging.
Despite proof that the substance is harmful to laboratory animals, DuPont officials insist that the balance of evidence proves it poses no threat to humans. They claim the corporation has used the substance successfully for more than 50 years without detecting any adverse effects.Dangerous Chemical or Harmless Ingredient?
The toxicity of the manufacturing chemical is currently under intensive review by the Environmental Protection Agency. In a draft risk assessment released in April 2003, the EPA determined that PFOA is prevalent, pervasive, and persistent. The assessment also indicated that the substance is known to cause cancer and developmental and reproductive problems in laboratory animals.
EPA has identified potential human health concerns from exposure to perfluorooctanoic acid (PFOA) and its salts, although there remains considerable scientific uncertainty regarding potential risks, said the EPA assessment.
But last week, the EPA announced that the Science Advisory Board, a panel of independent experts solicited to review the chemicals potential hazards, concluded that C8 was probably more hazardous than first suggested.
In considering the collective evidence the majority of panel members concluded that the experimental weight of evidence with respect to the carcinogenicity of PFOA was stronger than proposed in the draft document, and suggested that PFOA is a 'likely' carcinogen in humans," said the board in the draft, which can be viewed online at http://www.epa.gov/sab/panels/pfoa_rev_panel.htm.
The Science Advisory Board meets again today to review their draft report, which includes recommendations for stronger health precautions.
In response to last weeks announcement DuPont officials released the following statement:
Based on an evaluation of human health and toxicology studies, DuPont believes that the weight of evidence suggests that PFOA exposure does not cause cancer in humans, and does not pose a health risk to the general public. To date, no human health effects are known to be caused by PFOA even in workers who have significantly higher exposure levels than the general population."
Enesta Jones, EPA spokesperson, said it would be premature for the agency to weigh in on the panels report.
This is a draft report and well have more to say when its final, Jones said. The science isnt conclusive and neither is the report.
Once the Science Advisory Boards report has been finalized later this year the EPA will review it and decide what steps to take, Jones said. No specific timeline is in place for the final report or the agencys response, but the full plenary is scheduled to convene in Washington D.C., for their ninth session in October.
Drink at Your Own Risk
Locally, customers of the Little Hocking Water Association are getting a daily dose of PFOA in their water supplies, the result of emissions from the nearby DuPont Washington Works plant in West Virginia. Last weeks news from the EPAs Science Advisory Board prompted an influx of calls to the water association from concerned people, said Robert Griffin, Little Hocking Water Association general manager.
A year ago the rural water department issued a drink at your own risk warning to customers because of uncertainties about PFOA. The highest level of C8 entering the Little Hocking distribution system was measured at 7.2 parts per billion, but the highest well reading was 18.6 parts per billion. Although PFOA can be detected globally, the water association, which has a well field just across the Ohio River from the Dupont Washington Works plant, has a greater level of C8 in it supply than any other tested supply in the world, meaning that local consumers have a more direct route of exposure to the manufacturing chemical. Although more than 90 percent of Americans have C8 in their blood, scientists say people who live in the area and drink contaminated water may have the highest levels of exposure. Numerous tests are underway to determine the average level of human exposure in the Mid Ohio Valley.
The Little Hocking Water Association works with the Ohio EPA to test the wells quarterly and closely monitor the results. Griffin said results from a May sampling are due back any day.
As part of DuPonts $108 million settlement with class action members over the presence of C8 in local water supplies, if the substance is found to be harmful the corporation has agreed to embark on a long-term plan to provide Little Hocking Water Association customers with a filter system to remove the PFOA from their water. The corporation is proposing short-term solutions while testing is performed.
We think DuPont ought to look at a more permanent solution, Griffin said. We dont want to wait for testing. We want water without C8 in it now.
Pathways of Exposure
Following the lead of the Environmental Protection Agency, the Food and Drug Administration is investigating the DuPont manufacturing chemical and its potential pathways to human exposure. The largest EPA review of its kind has become a multi-agency effort to determine how the substance has become so prevalent that PFOA can be found in the bloodstream of more than 90 percent of Americans.
This has come up in recent years as a result of the EPAs activities, said Dr. George Pauli, FDA Associate Director for Science and Policy in the Office of Food Additive Safety. We are in the early stages of our research on it.
PFOA is not only used to manufacture Teflon, it is also a breakdown product of chemicals used to coat food packaging. Treated paper products such as French fry boxes, sandwich wrappers, pizza boxes, and microwave popcorn bags are often coated with fluorotelomers, which have the same non-stick, water and grease repellant properties as Teflon. These perfluoropaper coatings have a tendency to breakdown into PFOA when exposed to heat, causing potential migration of the substance into food.
DuPont spokesperson Leslie Beckhoff calls the chemical breakdown an unintended reaction in trace levels in some products.
The complete results of the FDAs research on potential food migration from food packaging will be published in the September/October edition of the Journal of Food Additives and Contaminants, Pauli said. But, last November in Barcelona, Spain, FDA researcher Timothy Begley revealed some of his preliminary findings while speaking at the Third International Symposium on Food Packaging.
Begleys oral presentation outlined specific testing done by the FDA in researching the potential food migration of PFOA. However, the study is not limited to exposure via Teflon cookware. On the contrary, Begleys preliminary findings show that PFOA is more likely to migrate from coated paper food packaging.
Begley concluded that PFOA does migrate from PTFE (Teflon), but that Teflon coated cookware does not appear to be a significant source of PFOA.
Paper coatings potentially are a significant source of fluorochemicals. Some paper applications (have) potentially 100 micrograms fluorotelomer per serving, Begley said.
Begleys presentation also indicated that little to no PFOA was found to migrate from popcorn bags, but that more work is needed to characterize the comprehensive exposure to fluorochemicals from food packaging.
Pauli said the amount of PFOA migration noted was well within safe levels as determined by the EPA, but the concern is because PFOA persists so long in the environment and in a persons blood.
Scientists from the Environmental Working Group who have been following the issue closely say that the FDA presentation is important because it confirms what many researchers have been saying for some time that the prevalence of PFOA in the blood of Americans is more likely coming from a list of many consumer products rather than simply from Teflon cookware. The EWG is a Washington DC-based research and advocacy group.
"With this study of what chemicals come off of popular food packaging, the FDA is asking the right questions, said EWG Senior Scientist, Dr. Tim Kropp. We need to know what toxic, cancer-causing chemicals are coming off of popcorn bags and other forms of fast food packaging such as pizza box liners or hamburger wrappers. When an indestructible Teflon chemical linked to cancer, birth defects and other health problems show up in 95 percent of Americans, it's time to take action."
The FDAs research has been complicated because the methodology for analyzing PFOA was not previously developed. In particular, Pauli said researchers initially found extraction of PFOA tricky because a couple of chemicals are so similar.
Methods are still being defined, Pauli said. We have received some cooperation from industry.
Pauli said the FDA was trying to develop a better understanding of the fraction of exposure attributed to food packaging as opposed to other consumer products.
Food packaging appears to be a minor source, Pauli said, predicting that the final report will make the issue much clearer when it is released in a few months.
The new information from the Science Advisory Board and the FDA, which are both expected to be released in their final forms later this year, are both smaller elements of the larger investigation by the EPA that will ultimately involve the development of voluntary enforceable consent agreements with industry users - a slow and deliberate process that could still be more than a year from any definite conclusions.
Background & Local Impact
The manufacturing chemical known as C8, PFOA, or perfluorooctanoic acid first came to the attention of Mid Ohio Valley residents in 2002 after it was detected in several of the areas public water supplies, including the Tuppers Plains Chester Water District, the Little Hocking Water Association, and the supplies for the cities of Pomeroy and Belpre.
Subsequent study revealed that the prevalent substance, which had been released into the Ohio River and a local landfill for five decades, could be detected in the air, water, and soil for miles around the plant. DuPonts Washington Works plant, located along the Ohio River near Parkersburg, West Virginia, uses C8 as a processing aid in the manufacture of non-stick Teflon and other fluorochemical finishes. Other corporations also use the chemical to make products such as Scotchgard and Stainmaster protective finishes, and Gore-tex weather-resistant clothing.
For many years, 3M was the only manufacturer of C8 in the United States, but in May 2000 the corporation discontinued manufacture of all products based on perfluorooctanyl chemistry.
Since 3M got out of the C8 business, the Washington Works plant is one of only two DuPont plants that produce or make PFOA in the United States. A second plant in Fayetteville, North Carolina began similar production in 2002 after being upgraded with millions of dollars in new technology in attempts to minimize emissions from the controversial chemical.
The discovery of C8 in local water supplies prompted a class action suit from many of the plants neighbors who fear the potential long-term effects of exposure from their contaminated drinking supplies. The detection of the presence of C8 also prompted intense review of the chemical by the EPA to determine the potential risk, if any, to humans from exposure.
DuPont is also coming under fire from the EPA for allegedly violating the Toxic Substances Control Act by not disclosing the results of studies conducted on pregnant employees two decades ago that revealed serious birth defects in two of seven babies born to a group of female workers. The study became public last year as the result of the class action lawsuit.
Because of the enormous amount of information-gathering necessary to evaluate any potential human health risk from PFOA exposure, in June of 2003 the EPA embarked on a process of study and negotiation involving voluntary enforceable consent agreements with affected manufacturers, and mobilizing the cooperation and resources of other interested parties, industry representatives, independent scientists, environmentalists, and other government agencies to collect, examine and share information about the substance.
DuPont recently settled the West Virginia lawsuit for $108 million amidst accusations that the corporation contaminated local drinking water supplies and failed to report the pollution it detected as early as 1984. DuPont officials maintain that the corporation has used the substance successfully for more than 50 years without any known adverse human health effects.
While the EPA review strives to define the risks of exposure and determine the possible pathways, many local residents are getting a daily dose of C8 through their tap water. Wells at the Little Hocking Water Association have inexplicably tested as high as 18.6 parts per billion, despite a $24 million effort by DuPont to reduce air and water emissions by 90 percent.
The Ohio EPA continues to monitor well testing, quarterly in Little Hocking and annually for the Tuppers Plains Chester Water District, to examine C8 levels.
For more information: DuPonts C8 Web site www.c8inform.com , Environmental Working Group www.ewg.org , Little Hocking Water Association www.littlehockingwater.org, Environmental Protection Agency www.epa.gov.