News Coverage
DuPont study finds no link between C8, health problems
Critics question how research was done, say results subject to misinterpretation
Published January 12, 2005
A DuPont study of 1,025 workers at its Washington Works plant along the Ohio River has found no link between major health problems and a chemical used to make Teflon.
Company researchers said the results of their study, released yesterday, shows perfluorooctanoic acid, more commonly known as PFOA or C8, had no effect on liver function, blood counts or cancer markers measured in exposed plant workers.
Tests showed that some employees who had high concentrations of the chemical -- as much as 1,000 parts per billion -- in their blood also had higher levels of bad cholesterol and fats.
Critics, however, say the results are not good.
"If this isn't a human health effect, what is?" said Tim Kropp, a toxicologist for the Environmental Working Group, an advocacy organization based in Washington, D.C.
C8 is an essential ingredient used to make Teflon and other nonstick coatings used in cookware, clothing and carpets. Trace amounts have been detected in humans and animals around the world.
Concern about the chemical's potential health effects led the U.S. Environmental Protection Agency to accuse DuPont of illegally withholding information and pushed the company to pledge up to $340 million to settle a class-action lawsuit.
Critics of the company question how the study was done and DuPont's interpretation of the results. Company officials, however, say C8 has never posed a health risk to humans.
"To date, there are no known health effects of (C8), but some things require further study," said Robert Rickard, a DuPont researcher who helped conduct the study.
Rickard said more work needs to be done to examine what he called modest increases in cholesterol and triglycerides and slight increases in uric acid and iron. The higher levels were detected in employees who had C8 blood concentrations greater than 1,000 parts per billion.
A study DuPont funded and received July 29 showed C8 at levels as high as 128 parts per billion in blood samples from 12 residents of Wood County, W.Va., where the Washington Works plant is located. An average of 5.6 parts per billion has been found in the general U.S. population.
While C8 is known to cause liver and developmental problems in lab animals, relatively little is known about its effects in humans outside of company studies.
The U.S. EPA has charged that DuPont illegally withheld internal studies of the chemical and reports that showed C8 was getting into Ohio and West Virginia drinking water near the Ohio River plant. The company, which argues that it did nothing wrong, faces government fines of as much as $300 million.
While DuPont continues to study its workers, a more far-reaching analysis is expected to begin this year in the area surrounding the plant.
DuPont's lawsuit settlement includes paying for a study of as many as 80,000 Ohio and West Virginia residents exposed to C8 in their drinking water. The work should begin after the settlement is finalized in late February, said Harry Dietzler, an attorney for the plaintiffs.
Dietzler also was critical of the DuPont study, questioning why researchers didn't examine area residents for such things as liver problems and cancer markers. Looking at workers alone is not good enough, he said.
"If you and I drink the same water and breathe the same air, a comparison between the two of us would be meaningless," Dietzler said.