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Teflon Is Not Forever: Why the Editors of Mother Jones
Need To Be Hit Over the Head with a Frying Pan

When your source for a scare is the Environmental Working Group, you end up with a scientifically illiterate story.

Forget about Global Warming for a moment. No-one – and certainly not the scientific community – seriously doubts that the earth is warming, even though there may much to debate about in the details of modeling the long term impact of such change on dynamic, non-linear systems. But why is it that environmental activists continue to expend huge amounts of energy warning us about things that the scientific community regards as having minimal or no risk to our lives? And why do journalists become so credulous and so unscientific when reporting on these risks?

These are some of the questions that emerge from reading Leslie Savan’s “Teflon is Forever” in the May-June issue of Mother Jones, a three-page expose that suggests the author and the editors either cannot distinguish between science and science fiction – or are so dogmatic in their anti-corporatism that they simply don’t care to. As Savan writes in her opening paragraphs, it is ironic

“that our favorite metaphor for bad press that won’t stick comes from a product whose toxic legacy will stick around forever. Teflon, it turns out, gets its nonstick properties from a toxic, nearly indestructible chemical called PFOA, or perfluorooctanoic Acid. Used in thousands of products from cookware to kids’ pajamas to takeout coffee cups, PFOA is a likely human carcinogen … it is now becoming apparent that cleansing ourselves of PFOA is nearly impossible.”

But this just isn’t true for a very basic scientific reason: PFOA has a half-life of 4 years in humans, meaning that it takes 4 years, on average, for half of the chemical to be excreted from our bodies. So, assuming that there is no ongoing exposure, “forever” really means less than a decade. In fact, one recent, albeit small, study (Olsen G.W. et al, Preliminary evidence of a decline in perfluorooctanesulfonate ..., Chemosphere 2007) found that PFOA concentrations in the blood plasma of American Red Cross blood donors in St. Paul, Minnesota had declined by 50 percent between 2000 and 2005. Another earlier study showed a similar decline in PFOA levels among the population in Germany.

Okay, so,you’re possibly thinking, what’s so great about that? Mother Jones may be exaggerating, but shouldn’t we be concerned about the fact that PFOA – a likely human carcinogen! – is so persistent  and hangs around in our bodies for this long?

Again, no; PFOA may be persistent, but that quality is linked to the fact that it is highly unreactive. In fact, almost all the PFOA in humans is bound to the albumin in blood plasma, which means it isn’t metabolically available to do damage. 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, thus confirming the lack of metabolic activity from the presence of PFOA.

Why then is PFOA “likely” to be carcinogenic?
If you give massive doses of PFOA to rats, they will develop tumors. One of the key carcinogenicity 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.

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.”

When the EPA’s Scientific Advisory Board (SAB) examined the draft report, it recommended (although based on a split decision) that PFOA should be upgraded to a “likely” human carcinogen on the basis that there might be other modes of action that could cause liver tumors – even though there was no evidence to suggest that there were or might be. The irony in the SAB’s argument that PFOA should be considered a “likely” carcinogen is that there is no data to actually put a quantitative value on how likely. In other words, the risk is hypothetical. (All the relevant documents and public submissions on the EPA’s risk assessment of PFOA can be found here.)

Because there is so much current research being undertaken on PFOA, the recommendation that it be reclassified as a likely carcinogen has not actually been accepted by the EPA, so PFOA remains a “suggestive “carcinogen.

Savan, however, mentions none of this; instead, she leapfrogs over all the existing data to imagine PFOA being declared “a proven” carcinogen in humans, in which case, an EPA spokeswoman says “this chemical could be banned.”

But why ask the EPA to comment on a hypothesis that goes way beyond the current data rather than tell readers what the EPA has, thus far, concluded, which is that it there is no sign that PFOA causes cancer in humans?

Perhaps the confusion derives from Savan’s misunderstanding of what the EPA means when it declares a chemical to be a “likely” carcinogen.

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 by the EPA 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.

Caffeic acid, for instance, was long considered a “suggestive” carcinogen in humans, because high exposure in mice produced lung and other tumors; it is still listed as such; but no-one seriously thinks that the toxicity data implies that you can get cancer from eating apples, pears, plums or potatoes, all of which contain naturally-occurring caffeic acid!

The fundamental principle in toxicology is that the dose makes the poison.

Is DuPont acting like “Big Tobacco?”
Savan’s failure to systematically analyze the data in an open-minded manner leads her towards the most controversial charge in the Mother Jones article - that DuPont is playing a similar game with the evidence as “Big Tobacco” did with lung cancer and the Global Warming skeptics are presently doing. As Savan writes

“DuPont is hardly unique in trying to cast unflattering data as incomplete or uncertain. As epidemiologist David Michaels wrote in a 2005 essay in Scientific American titled “Doubt is their Product,” many corporations have followed the tobacco (and more recently, global warming) model of insisting that the scientific jury is still out, ‘no matter how powerful the evidence.’”

First, Michaels makes no reference to DuPont or PFOA in his article. Second, this is an ingenious defense of Savan’s own incomplete reporting. Third, the inference from tobacco or global warming denial to PFOA is scurrilous: the epidemiological evidence linking smoking to lung cancer is overwhelming; the data showing that the earth is warming is incontrovertible; there is, however, no study that has demonstrated that PFOA exposure causes any negative health outcome in humans. Thousands of scientists are not warning the public about the risks from PFOA, and the approach of regulatory bodies to the data reflects a methodological consensus in toxicology.

Savan, as noted, doesn’t seem to understand such a basic concept in toxicology as half-life. By claiming that DuPont’s protestations are a deception on a par with the Tobacco industry Savan evades the fundamental issue of what makes some scientific data and arguments strong and reliable and others weak and unreliable. Instead of looking at the data dispassionately, Savan and Mother Jones leap to a muckraking conclusion. And this failure to report with an open mind, is only underscored by the more basic errors “Teflon is Forever” makes.

One birth defect or multiple birth defects among DuPont Workers’ children?
Savan charges that the EPA fined Dupont for not disclosing that workers were reporting health problems for years, including birth defects in their children.

"As far back as 1981, DuPont scientists knew that PFOA could cross the placenta and thus contaminate fetuses. DuPont also knew that some of its workers' babies had been born with eye defects similar to those 3M had just then reported in rats exposed to PFOA."

The charge that PFOA was connected with birth defects is based on just one case. As CBS News reported in February 2006:

"Sue Bailey believes PFOA is why her son has severe facial defects. He was born in the 1980s, when she worked around PFOA chemicals at Dupont and she remembers a Dupont doctor calling her shortly after the birth. 'He was asking all these questions, wanting to know what the deformity was,' Bailey told Attkisson. 'I asked him why he needed to know that and he told me that any time there was a birth defect or a deformity they had to know all about it because it had to be reported. But they did not report it.'"

One case of deformity from one person (among thousands) who worked with PFOA is an association that is statistically meaningless, especially when there isn't a single health study that has ever shown any such association. But more importantly, Bailey’s case was reviewed by one of the top experts in the country on birth defects, John M. Graham, Jr. Director of Clinical Genetics and DysmorphologyCedars at Sinai Medical Center in Los Angeles. He stated that the birth defect “was a rare but well understood genetic condition and was not caused by PFOA.”

Why weren't Mother Jones readers told this - even as a matter of journalistic balance rather than a refutation?

The EPA DuPont fine
To add real luster to a scare story, it always helps if the manufacturer of the alleged poison engaged in some cover-up, and Savan thinks that she has found the evidence in the EPA’s fine.

“DuPont has always known more about Telfon than it let on. Two years ago, the EPA fined the company $16.5 million – the largest administrative fine in the agency’s history – for covering up decade’s worth of studies indicating that PFOA could cause health problems such as cancer, birth defects and liver damage.”

One might be inclined to think that a fine is a brute fact – someone did something wrong, and they got slapped for it. That’s how most of the media reported it at the time. But as an analysis of the fine in the New York Law Journal article Disclosure on Trial: "Substantial Risk" Reporting Requirements (follow the internal link) shows,

"the thrust of the EPA's enforcement action against DuPont was that evidence that a community is being exposed to a chemical triggers ‘substantial risk’ reporting, even if exposure is below bench-mark risk based standards."

In other words, DuPont was fined not because it failed to disclose information that showed an actual risk to the public, but because there was a "significant change in the agency's position as to the scope of the statutory duty to disclose 'substantial risk' information," according to the authors of the article, Philip E. Karmel and Peter R. Paden, who are partners at Bryan Cave LLP.

Prior to the DuPont case, the EPA's policy on disclosure (established in a 1978 policy document) did not require companies to report exposure levels to chemicals that are below EPA-set benchmarks. And as the article notes, DuPont believed it had fully complied with the EPA's statutory requirements. The EPA, however, leveled three complaints against DuPont for:

  • The failure to report a sample of umbilical cord which showed trace concentrations of PFOA. The mother was a DuPont employee.

  • The failure to report data showing drinking water wells had PFOA levels that exceeded DuPont's internal community exposure guideline of one part per billion (ppb).

  • The failure to report a test showing that 12 people tested in the vicinity of a DuPont plant had elevated levels of PFOA in their blood.

In each case, as karmel and Paden point out, there were logical reasons for non-disclosure. For example, the levels of PFOA in well water (between 0.8ppb and 3.9ppb) were "more than an order of magnitude lower than the 150ppb concentration level established as posing 'no risk of deleterious [health] effects by a panel of scientific experts, including three EPA scientists and a scientist from the federal Agency for Toxic Substances and Disease Registry."

Popcorn bags
One of the ways we are exposed to PFOA, Savan claims,  is through food packaging:

“Pizza-slice paper, microwave popcorn bags, ice cream cartons, and other food packages are often lined with Zonyl, another DuPont brand. Technically, Zonyl does not contain PFOA, but it is made with flurotelomer chemicals that break down into PFOA. Regardless of how it gets into our bodies, once there, PFOA stays – quietly accumulating in our tissues, for a lifetime.”

This claim was made by ABC investigative reporter Brian Ross in a segment for Good Morning America on November 18, 2005, driven by the statements of a whistleblower from DuPont put on display by the Environmental Working Group. There was, as STATS pointed out at the time, a lot wrong with this story, but the salient point for those about to microwave some popcorn is that the Food and Drug Administration responded to this issue at the time with a public letter that stated:

“…it should be noted that this flurotelomer migration from coated paper, as reported in this article [Begley, T., et al Food Additives and Contaminants 22 (10) 2005] occurs in the form of telomer-based compounds themselves and should not be equated with PFOA exposure.”

In fact, the only evidence for the kind of transmutation described by Savan is a study that found that one percent of a precursor chemical to the flurotelomer coating – flurotelomer alcohol – was metabolized into PFOA in rats.

But here’s the rub: what makes the flurotelomer coating so stain resistant – the carbon-fluorine bonds – is precisely what makes flurotelomers difficult to break down in the blood to monomors like flurotelomer alcohol , where they could then be metabolized into PFOA.

There is no evidence, as yet, that this happens or even might happen in humans. But if it did, flurotelomer alcohol has a very low metabolic rate, which means that most of it would be quickly excreted from the body anyway.

What Savan has written about Zonyl RP is simply not backed by any science. But what is more troubling is that Savan doesn’t tell Mother Jones readers that the Food and Drug Administration has, in fact, looked at PFOA migration from microwave popcorn bags and found that the level is “below the level of quantitation using current analytical methods,” which is to say, lower than one part per billion.

Elegant propaganda
Savan has written an elegant and compelling story; if you didn’t know anything about science, or had followed this issue with analytical avidity, you might think it was true – and that Mother Jones was holding truth to power, and providing a public service that accords with the highest ideals of journalism.

Yet it is clear from the compounded errors in "Teflon is Forever" that neither Savan nor Mother Jones looked at the science behind this controversy. Instead, their litany of facts seems entirely derived from one activist group, the Environmental Working Group, which has a long track record of whipping up hysteria over issues that, upon closer inspection, evanesce. This group also has a habit of making definitive scientific claims based on limited data and impeachable methods, such as when they warned about PCBs in salmon based on a sample of ten fish from around the country. And, like many a group with an agenda, the Environmental Working Group is uninterested in evidence that contradicts its policy positions.

On a purely technical level, “Teflon is Forever” is appallingly sourced. But there is more at stake here than the basic ethical requirement that Mother Jones listen to the other side out of a sense of fairness, or consider whether the evidence Savan has marshalled stands up to scrutiny from independent experts; journalism has a moral imperative to shout fire when there’s fire in the theater, not simply because someone may be carrying a box of matches. With all the real threats to public health, we need to be actively protected from imaginary ones.

Editor's note: some typographic and style changes were made to this article on March 19, 2008


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