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Is Teflon Chemical Toxic? EPA Seeks Answers
PFOA in Everybody's Blood, but Is It Harmful to Humans?
Jan. 13, 2005 -- A chemical used to make Teflon somehow got into the blood of everybody on earth. How did it get there? What does this mean for our health?
These are very important questions, says the Environmental Protection Agency. The answer? Nobody knows. To find out, the EPA has assembled a distinguished panel of outside experts. But they don't start work until next month. Meanwhile, the long-lasting chemical continues to accumulate in the environment -- and in our bodies.
Toxicologist Tim Kropp, PhD, senior scientist with the watchdog group Environmental Working Group, finds the situation alarming.
"It doesn't break down -- ever. It is the most persistent synthetic chemical known to man," Kropp tells WebMD. "It would take your body two decades to get rid of 95% of it, assuming you are not exposed to any more. But you are."
The chemical is PFOA, sometimes called C-8. It's used to make Teflon - made by DuPont -- and many, many other products. But DuPont says PFOA is used only during the manufacturing process and that there's no PFOA in Teflon cookware or other Teflon products.
PFOA gets into the environment during the manufacturing process. Indeed, the EPA and DuPont are squabbling about millions of dollars of EPA-assessed fines for allegedly slow reporting of PFOA data.
But people who live nowhere near PFOA manufacturing sites have PFOA in their blood. How that happened, and what it means for their health, is a mystery, says Jennifer Seed, PhD, EPA chief of pollution prevention and toxics in the risk assessment division of the Existing Chemicals Assessment Branch.
"PFOA is present in most people's blood in this country and beyond; it's even in wildlife," Seed tells WebMD. "We have absolutely no understanding at this point how it got there. It is like fairy dust."
That's scary. So are data from animal studies showing that PFOA causes cancer, liver damage, growth defects, immune system damage, and death in lab rats and monkeys.
"Those are the potential hazards. How those relate to humans is the key question. That is the one we have been grappling with," Seed says.
Is It Dangerous to Humans?
Studies of people who work with PFOA -- mostly men -- show they have much higher PFOA blood levels than most other people. These workers tend to have high cholesterol levels. But DuPont's chief medical officer, Sol Sax, MD, says the studies don't directly link any bad health outcomes to PFOA.
"The association of PFOA with the increases in total cholesterol and the other endpoints in this study was observed in people in an industrial setting," Sax says in a news release. "Given the extremely small levels of PFOA exposure generally seen outside the work setting, it is my medical opinion that no association would be seen in the general public."
The EWG's Kropp sees it very differently.
"They say the cholesterol finding isn't relevant to most people because their PFOA blood levels are lower than those of workers," he says. "But the range of blood levels in workers and normal people overlap. And if the high-exposure people have a 10% increase in bad cholesterol, and normal human exposures cause 'only' a 5% increase -- well, nobody wants a 5% increase, either. Just because workers have higher PFOA levels doesn't mean there is no effect at lower levels."
Seed says there's no way anybody can say for sure whether PFOA is harmless or dangerous.
"It is certainly bad for the monkeys. It is certainly bad for the rats. But like medicine, it is all in the dose," she says. "If you drink too much water or take too much thyroid medicine, it is bad for you. PFOA is bad for the monkeys, but not at all doses -- just when you reach a certain point. So the question is, how do you know when people have reached that point?"
To find out, the EPA is calling together a panel of 17 experts. Leading the panel will be Deborah Cory-Slechta, PhD, director of the Environmental and Occupational Health Sciences Institute at Robert Wood Johnson Medical School in Piscataway, N.J.
The panel will meet in February to address the questions regarding PFOA.
Seed notes that this isn't the first time the EPA faced this kind of problem. A chemical very similar to PFOA, called PFOS, was used by 3M Corp. to make Scotchgard and other products. In May 2000, after negotiations with EPA, 3M phased out PFOS use. |