News Coverage
DuPont Chemical Worries Ohio EPA
Published February 23, 2003
Ohioans have been exposed to airborne levels of the DuPont chemical C8 that were nearly three times as high as the company's own community standard.
The Ohio Environmental Protection Agency is concerned that short-term concentrations might be harmful to people exposed to the chemical, which DuPont has used for more than 50 years to process Teflon and related coatings at a plant along the Ohio River west of Parkersburg, W.Va.
Levels of C8 in the air across the river in Washington County have been higher than workplace standards for the chemical, EPA Director Christopher Jones wrote in a Jan. 7 letter to DuPont's plant manager.
Residents might not be exposed to C8 as frequently as some workers, but concentrations detected in Ohio "raise our level of concern with regards to short-term exposures to workers and sensitive populations,'' Jones wrote.
DuPont has asked for a meeting to discuss the Ohio EPA's concerns. In an e-mail response to questions from The Dispatch, the company said it thinks that C8 levels detected in communities near the plant are "not harmful to either human health or the environment.''
The Dispatch reported last Sunday that DuPont has known for more than two decades that C8 has contaminated drinking water on both sides of the river.
Research dating from the 1970s by DuPont and 3M, which used to be the chief supplier of the chemical, shows that C8 builds up in human blood, doesn't break down in the environment and might cause serious health problems, including cancer and liver damage.
Emissions of C8, also known as ammonium perfluorooctanoate, aren't regulated. But amid growing concerns about the chemical's persistence and potential health effects, the U.S. EPA launched a high-level investigation in September that could lead to national standards.
Federal officials became concerned about long-term emissions of C8 after 3M studies revealed the chemical has been found in human blood and food across the nation, a discovery that suggests C8 travels freely through air.
Pressed by the U.S. EPA to curb the spread of C8 and related chemicals in the environment, 3M decided in May 2000 to stop manufacturing them. DuPont now makes C8 at a plant in Fayetteville, N.C.
Based on earlier research, DuPont in 1988 established a "community exposure guideline'' of 0.3 micrograms of C8 per cubic meter of air, according to company documents. Workplace limits are more stringent: 0.1 micrograms per cubic meter.
In September, after computer modeling done by DuPont and the state of West Virginia confirmed that DuPont's air emissions were much higher in surrounding communities, the state declared that the "safe level'' of airborne C8 is 1 microgram per cubic meter, more than three times as high as DuPont's standard.
"Our staff toxicologist and other experts in the field had human health and safety in mind when they developed limits for DuPont to follow,'' Michael Callaghan, then-director of the West Virginia Department of Environmental Quality, said when the air standard was announced.
Two months earlier, a consultant hired by West Virginia to help develop the standard recommended that it be set at 0.3 micrograms per cubic meter, identical to DuPont's community standard.
The lower level "is more protective of public health,'' Joan Dollarhide of TERA, a consulting firm based in Cincinnati, wrote in a July 12 e-mail distributed to West Virginia officials.
"Given the existing uncertainties and the uproar at this site, it makes sense to be as conservative as is reasonable,'' Dollarhide concluded.
Independent analysis is practically impossible because there is no known method to routinely test the concentration of C8 in the air. Air monitors posted around the state aren't designed to measure the chemical, said Bill Spires, an Ohio EPA meteorologist.
The air levels detected to date in surrounding communities are based on U.S. EPA-approved computer models of C8 emissions from the DuPont plant and regional weather patterns.
DuPont's modeling for 2000 found maximum C8 concentrations of 2.7 micrograms per cubic meter at the plant fence, 0.8 micrograms per cubic meter across the river in Ohio and 0.2 micrograms per cubic meter in nearby West Virginia communities. Preliminary modeling of air emissions during 2002 indicates that C8 concentrations are below the West Virginia standard "and will remain below that level in the future,'' DuPont said in its e-mail response to The Dispatch.
Under agreements with West Virginia and the U.S. EPA, DuPont plans to cut air emissions of C8 to half of 1999 levels by the end of the year. But the Ohio EPA wants the restrictions written into permits that are enforceable under the federal Clean Air Act.
"We do not believe that there is enough certainty in the assumptions to insure that future ambient air impacts will be significantly below 2000 levels,'' Jones wrote in his letter to DuPont's plant manager.
Researchers think C8 is contaminating drinking-water supplies in part through the air. Among the Ohio towns where C8 has been detected in water is Belpre, 4 miles upriver from the plant.
The debate about an air limit for C8 has been similar to one for drinking water.
In 1991, DuPont set a community-exposure guideline of 1 part per billion in water, a limit that the company continued to cite in internal documents as recently as November 2001.
Last year, after DuPont contractors detected much higher levels in wells of the Little Hocking (Ohio) Water Association, West Virginia officials declared that the safe level of C8 in water is 150 parts per billion. Little Hocking's well field is across the river from the DuPont plant.
"This whole thing has been surreal from the beginning,'' said Robert Griffin, general manager of the Little Hocking system.
"DuPont knows more about this than anybody else,'' Griffin said. "They came up with their own community standards for a reason.''
Earlier stories on C8 are archived at www.dispatch.com under the Special Reports link.