DuPont and other companies have reduced their emissions and agreed on a voluntary phase-out of the chemical, but researchers are still concerned about a growing list of possible health effects and about the chemical's presence in consumer products, as well as continued pollution from waste disposal practices.
Despite years of study and many promises of action, EPA has never set formal regulatory limits for the amount of C8 that can be discharged into the air or water.
In January 2009, just as the Bush administration was leaving office, EPA issued a nationwide "provisional health advisory" that urged Americans to reduce consumption of any water that contains more than 0.4 parts per billion of C8. And then in March 2009, EPA toughened a legal settlement with DuPont, requiring the company to provide replacement water supplies for anyone in the Parkersburg area whose drinking water contains more than 0.4 parts per billion of C8. Originally, DuPont was required to replace water supplies if C8 was higher than 150 parts per billion. That figure was tightened to 0.5 parts per billion in 2006.
In a 2009 paper, researchers from the New Jersey Department of Environmental Protection and Rutgers University concluded that the EPA's C8 advisory was not strong enough and did not consider some adverse health effects that could occur at very low exposure levels.
Many researchers are concerned about studies that have found C8 associated with adverse health impacts at levels below those currently found in the general U.S. population. Much of the exposure to C8 could be coming from consumer products, some researchers believe, but it's not clear how the chemical could also be coming from water supplies around the country.
In an email response to the Gazette-Mail, EPA regional spokeswoman Terri White defended the agency's actions so far related to C8.
"The provisional health advisory remains the best available action level for PFOA at this time," White said. "EPA is developing a revised health advisory that will likely be available within the next year.
DuPont spokeswoman Janet Smith said that her company is aware that EPA "is finishing a health advisory" for C8 in drinking water and is "confident that they will include all relevant data in their assessment."
But Cincinnati lawyer Rob Bilott, who has for years urged EPA to set enforceable water pollution limits for C8, said that the new Harvard paper "highlights the urgent need for regulatory agencies to consider the most recent human health and toxicology data to set appropriate safety limits for chronic, long-term exposures to PFOA in drinking water.
"The current EPA guidelines were released years before much of this important new data came to light and are designed to address only short-term exposures -- not situations where people are drinking contaminated water over many years," Bilott said.Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.