DuPont Co. has found high levels of the toxic chemical C8 in the blood of workers at a new Teflon plant in China, despite company promises to greatly reduce exposures and emissions.
Less than a year after the plant began operations, workers already have an average concentration of C8 in their blood similar to — or greater than — found in previous studies of U.S. plant workers.
“The increase in the blood levels is just staggering,” said Richard Wiles, director of the Environmental Working Group, who monitors C8 issues. “It raises a lot of concerns.”
Workers tested in May at DuPont’s plant in Changshu, China, had an average blood concentration of about 2,250 parts per billion of ammonium perfluorooctanoate, or PFOA. That compares to an average of just less than 50 parts per billion in May 2007, before the plant was operational.
The most recent figures show average C8 blood levels ranging from 60 to 1,600 parts per billion at DuPont plants in Deepwater, N.J., and Parkersburg, W.Va.
And, the Chinese numbers are much higher than previously reported average C8 blood concentrations among DuPont workers of 500 to 800 parts per billion and among some workers at 3M Corp. C8 facilities of 2,200 parts per billion.
In August, DuPont reported the new Chinese data to the U.S. Environmental Protection Agency as required under federal toxic chemical control laws.
“Although the reported blood levels of workers at our Changshu site are well within the range of occupational exposure to PFOA, we clearly are not satisfied with the results,” company spokesman Dan Turner said in a prepared statement.
DuPont has used C8 since the 1950s at its Washington Works plant. The chemical is a processing agent used to make Teflon and other nonstick products, oil-resistant paper packaging and stain-resistant textiles.
Researchers are finding that people around the world have C8 in their blood in low levels, with the average American having 4 to 5 parts per billion in their blood. Evidence is mounting about the chemical’s dangerous effects, but regulators have not set a federal standard for its safety. Scientists are still sorting out exactly how humans are exposed, but previous studies show food and food packaging, Teflon pans, household dust and drinking water are possible sources.
DuPont has promised to make major emissions and worker exposure reductions, and to cut by 97 percent the amount of C8 that leaches into consumer products.
When it opened the Changshu facility, DuPont installed its new Echelon technology. DuPont says this technology allows it to make “low-PFOA” products. The plant was also to include controls to limit C8 emissions and worker exposures.
“Significant improvements in ventilation and air turnover have already been made at the Changshu site,” DuPont’s Turner said. “We are confident that these actions have significantly reduced exposure.
“Our objective is to minimize worker exposure to PFOA in our global facilities,” Turner said. “We will continue to monitor potential workplace exposure and reduce levels through our industrial hygiene program.”
But, Chinese workers are showing much larger C8 blood levels than those found when DuPont started making C8 in 2002 at its facility in Fayetteville, N.C. DuPont started that C8 production to replace the company’s supply after 3M stopped making the chemical.
At Fayetteville, average worker C8 blood levels increased from a baseline of 11 parts per billion in late 2002 to 951 parts per billion in December 2005.
“If we’re seeing this level in the blood of Chinese workers at what they are calling a state-of-the-art plant, you have to wonder about the emissions to the air and the water and about PFOA levels in their products,” said Wiles of the Environmental Working Group.