When Good Science is Bad Politics

A troublesome family of synthetic chemicals called PFCs—many of them produced in Minnesota—is turning up in the bodies of people and animals worldwide. So why did the Minnesota Pollution Control Agency force its leading PFC researcher, Dr. F

T HE FIRST INTENSIVE RESEARCH into the presence of PFCs in Minnesota's environment commenced almost by accident. In 1997, the 3M Company—which manufactured PFCs for application in an array of products designed to resist heat, stains, and water—was conducting routine tests on its workers at a plant in Cottage Grove. For control purposes, the company also obtained blood samples from the Red Cross. The findings were startling. It wasn't just that the blood from employees was contaminated with PFCs. That much had been known for at least two decades. But almost all the samples taken from the general population also contained detectable levels of two PFCs that were manufactured by 3M—PFOS (which was used in Scotchgard) and PFOA (used in nonstick cookware and produced by the breakdown of other PFCs used in fast-food wrappings and other stain-resistant coatings).

Dan Picasso

From the perspective of both public health and corporate liability, the implications of the blood findings were patently worrisome. So worrisome, in fact, that 3M proceeded to commission a series of studies aimed at more broadly gauging the extent of PFOS distribution in the environment. If the results of the blood bank tests were a surprise, what came next was an even bigger shock. Trace levels of PFOS were turning up in blood samples taken from animals across the globe: polar bears in the Arctic, albatrosses in the Pacific Ocean, and turtles in the southeast U.S. were all affected. In other words, PFOS seemed to fit the textbook definition of what environmental scientists refer to as a "persistent bioaccumulative toxin." The revelations were so startling that within a year 3M promised the Environmental Protection Agency that it would entirely phase out its production of PFOS-related PFCs.

That most people currently living on this planet have been exposed to PFCs is now a matter of received wisdom. If you are like 90 percent of the population, there are detectable levels of a PFC in your blood serum. And if you happen to live near former 3M waste disposal sites in Cottage Grove or Oakdale—where PFCs have found their way into the aquifers and contaminated drinking water supplies—you likely have even higher levels. Because of the peculiar durability of these compounds, their continued presence in the environment (and in people and animals) is virtually assured. The most pressing question, then: Is exposure to PFCs hazardous to your health? If so, at what level? On this point, there is considerable uncertainty within the scientific community. The two U.S. corporations mostly closely associated with PFCs—3M and Dupont—have both consistently contended that PFC exposure does not constitute a threat to human health. They also both face class action lawsuits from people who don't believe that's the case.

In a letter to an EPA science advisory board last June, Dr. Larry Zobel—vice president and medical director at 3M—contended that long-term mortality studies of 3M workers at Cottage Grove did not suggest any increased cancer rates from exposure to PFCs. That was significant, since 3M workers had some of the highest PFOA exposure on record. Zobel acknowledged that one study examining health outcomes at another 3M facility located in Decatur, Alabama, did suggest higher rates of bladder cancer. But those results, Zobel added, were "not confirmed by a subsequent incidence study." For its part, Dupont has been more recalcitrant in its assessment of potential hazards of PFOA, a compound the company has long used in the manufacture of its blockbuster product, Teflon-brand nonstick cookware. Dupont, which continues to manufacture Teflon, has paid a price for its handling of the issue. Facing allegations that it concealed scientific evidence about potential health and environmental hazards, the company was targeted in a federal probe. In December, it agreed to pay the EPA more than $10 million in fines and to fund more than $6 million of research.

None of that has stanched the concern over the ubiquity of PFCs. For instance, while Dupont has continued to insist that consumers need not fear their cookware, the company has acknowledged that the same cannot be said of their pet birds. That's because overheated Teflon pans can release fumes that are lethal to birds. According to the Washington, D.C.-based Environmental Working Group, each year hundreds of so-called "canaries in the kitchen" die from exposure to the fumes. Certainly, birds have different and much more fragile respiratory systems than people. But the phenomenon, referred to as "Teflon toxicosis," can also manifest itself in nonfatal form in humans who inhale those same fumes, in a flu-like condition called polymer fume fever.

In May 2000, Charles Auer, the director of the EPA's Chemical Control Division of the Office of Pollution Prevention and Toxics, put the emerging view of PFOS in a stark perspective. "PFOS accumulates to a high degree in humans and animals," Auer wrote. "It thus appears to combine persistence, bioaccumulation, and toxicity properties to an extraordinary degree." For Dupont and 3M, the most legally problematic finding regarding PFOA, meanwhile, came this February, when a 16-member EPA scientific advisory panel recommended that the EPA classify the compound as a "likely human carcinogen."

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