STATS ARTICLES 2006

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More Crazy Teflon Coverage
January 27, 2006
Trevor Butterworth
No need to throw out your frying pan, “right now,” says ABC’s Brian Ross

Based on the most recent data from the Centers for Disease Control, we can expect some 680,000 people to die from heart disease in the United States in 2006. Cancer will claim around 550,000 lives; stroke, 150,000; chronic lower respiratory diseases, 120,000; diabetes, 70,000, influenza and pneumonia, 65,000; liver disease and cirrhosis 27,000. Many more people will die of other illnesses, and many more still will succumb to life-threatening diseases. What is unlikely – so highly unlikely as to be incredibly unlikely – is that anyone will suffer any ill effects from being exposed to Perflurooctanoic Acid (PFOA).

PFOA is an essential and currently irreplaceable precursor chemical used in the manufacture of fluropolymer coatings, such as Teflon, and flurotelomer coatings. These coatings perform critical roles in industrial and technical environments, such as insulation for wire and cabling, low emissions fuel hoses and pollution filters. Fluorotelomer coatings protect doctors and nurses against bloodborne pathogens and are used in firefighting. The manufacturing process destroys most PFOA – and tests show that even under extreme exposure conditions, there is no detectable PFOA exposure from cookware and only negligble amounts from carpeting.

The reason that we can say, with a high measure of confidence, that no-one will suffer illness from exposure to PFOA is simple: no study has ever shown that the trace levels of PFOA in the blood of most Americans (and most people on the planet) has ever resulted in any illness. Extensive studies of workers exposed to much higher levels of PFOA in chemical plants have never found any association between the chemical and illness of any kind. Indeed, as virtually all of the PFOA in human blood is bound to the albumin in blood plasma, it is not biologically available to do any damage. So the absence of provable ill health from the chemical is not difficult to explain. And contrary to widely-reported claims by the Environmental Working Group, PFOA is not “indestructible” - it has a half-life in humans of four years.

And yet, if you were to turn on the TV or read a newspaper this week, it would be difficult not to come away with the impression that a dangerous chemical was loose in the environment and that a voluntary pact brokered by the Environmental Protection Agency with eight chemical manufacturers will, as the Washington Post reported, “have profound implications for public health and the environment.”

The Post didn’t actually explain what these implications were or why they were profound; it simply noted that the EPA was concerned about PFOA and that the agency believed that reducing it was “the right thing to do for our health and our environment.”

Concern morphed into a much greater threat in the pages of The Chicago Tribune, which reported that “The EPA plan would classify PFOA as a persistent bioaccumulative toxin --a pollutant that builds up in people and animals and takes years to break down. Substances in that category include mercury, lead and polychlorinated biphenyls, or PCBs. The agency says ‘relatively small amounts’ of such substances ‘can pose human and environmental health threats.’”

But note, what the EPA did not say, and has never said, is that “relatively small amounts” of PFOA “can pose human and environmental health threats.” The Tribune simply damns by association – and a dubious one at that (The Food and Drug Administration and World Health Organization disagree with the EPA over the degree of risk from PCBs).

In fact, to judge by the EPA’s preliminary safety report on PFOA, the news this week is really all about precaution – and precaution that might well prove unnecessary given the state of the scientific research into PFOA.

At the EPA, any substance that can be shown to cause cancer in an animal in a laboratory setting is, classified as a “suggestive” carcinogen. And any substance that causes cancer in two animal species or both sexes of the same animal or more than one type of cancer in one species (provided the mode of action that caused the cancer is applicable to humans) is classified as a “likely” carcinogen. But neither the designation “likely” or “suggestive” means that the substance is likely to cause cancer in humans – or that it is even a human carcinogen.

In fact, dosing animals with massive quantities of chemicals to determine whether something is a “likely” or ”suggestive” carcinogen is far more controversial than most people think: a STATS survey in 1993 of 401 randomly chosen members of the American Association for Cancer Research found that only one in four thought that cancer-causing agents were unsafe regardless of the dose (28 percent). Similarly, only one in four (27 percent) endorsed the practice of assessing human cancer risks by giving animals a maximum tolerable dose of a suspected carcinogen.

But whether you agree or disagree with this practice or not, the EPA’s manner of designating whether something is a carcinogen primes the media to go into health scare mode: Once journalists hear that something is a “likely” carcinogen, they assume the risk demonstrated in animal experiments seamlessly translates into a corresponding risk to public health.

This is not the case with PFOA. One of the key studies showed that ten percent of rats dosed with PFOA levels at 125 parts per million developed a type of tumor in the liver produced by peroxisome proliferation. This exposure level is 25,000 times higher than the level of PFOA currently found in Americans, which is five parts per billion.

But in a presentation at a conference in August 2005, Dr. Jennifer Seed of the EPA’s Risk Assessment Division Office of Pollution Prevention and Toxics noted in her overview of the EPA’s assessment of PFOA that, “The overall weight of evidence suggests that the MOA [mode of action] for liver tumors is unlikely to occur in humans, taking kinetics and dynamic factors into account.”

Thus the EPA saw only “suggestive evidence of carcinogenicity.” Seed also noted that “Studies have not shown any effects directly associated with PFOA exposure." These comments came after the EPA’s Scientific Advisory Board had reviewed a draft risk assessment of PFOA. (The final report has not yet been published.)

In other words, the real news in this story is that the EPA and the chemical companies have decided to take an extremely risk averse position on PFOA because of its presence in the environment and blood, but not because there is any evidence as yet to suggest that there might be a genuine risk to humans.

In fact, the EPA Administrator Stephen L. Johnson, reiterated this point at this week’s press conference: “Although our risk assessment activities are not complete and new data may change the current picture, to date EPA is not aware of any studies specifically relating current levels of PFOA exposure to human health effects.”

The EPA also stressed that consumers had nothing to worry about from consumer products such as frying pans. Indeed, unless your kitchen doubles as a fully-equipped scientific laboratory and you, basically, dissolve your frying pan into a smoothie, there is no real-life way of absorbing any PFOA from a Teflon-coated pot or pan.

But over at ABC News, Brian Ross and Elizabeth Vargas were not quite convinced: “As for all those pots and pans in the homes of Americans, both DuPont and the federal government say there's no need right now Elizabeth, to throw them out,” said Ross. “No need to throw them out, but it seems like plenty of need for concern,” responded Vargas.