Coming Clean

Did 3M and DuPont ignore evidence of health risks?

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On May 16, 2000, the 3M corporation stunned the rest of the chemical industry with an unexpected announcement: It had decided to stop producing a family of compounds used in Scotchgard, Teflon, and a host of other consumer products. Saying that the “perfluorochemicals” it had manufactured for half a century had been found to persist in human blood and wildlife, 3M portrayed its move as that of a conscientious corporate citizen. “While this chemistry has been used effectively for more than 40 years and our products are safe,” declared Charles Reich, a 3M executive vice president, “our decision to phase out production is based on our principles of responsible environmental management.”

Reich, as it turns out, left out a few details. According to internal company documents obtained by Mother Jones, 3M, which makes Scotchgard, and DuPont, which makes Teflon, have suspected for decades that the chemicals pose serious health hazards. The first warnings came in the late 1970s, when 3M sponsored studies of perfluorooctane sulfonate (PHOs), a compound used to make fabric protector, semiconductors, photographic lm, and aircraft hydraulic fluid. Rhesus monkeys fed PHOs suffered diarrhea and yellowish-brown discoloration of the liver; every monkey exposed to the chemical died.

More evidence emerged in 1981, when both 3M and DuPont grew worried about the risk of birth defects among children born to workers exposed to the chemicals. 3M transferred 13 female workers of childbearing age out of its plant in Decatur, Alabama, after PHOs was detected in their blood. That same year, DuPont reassigned 50 women at its plant in Parkersburg, West Virginia, whose blood contained a related compound called perfluorooctanoic acid (PHOa), a soaplike substance used as a processing aid to make Teflon. Both companies eventually decided there was no risk of birth defects and allowed the women to return to work. But from that point on, both companies clearly knew that the substances could be absorbed by the human body.

Over the past decade, the warning signs have mounted. Studies show that perfluorochemicals are turning up in eagles, mink, polar bears, and other creatures. Rich Purdy, an ecotoxicologist who spent 19 years at 3M headquarters in St. Paul, Minnesota, before resigning last year, says he warned company ofcials in 1998 about PHOs levels in the environment high enough to kill wildlife. “There was no response,” he says. “They’d just kind of hear me out.” The company remained slow to react, he adds, even as data piled up.

Company officials insist that they acted promptly once they discovered that PHOs and its relatives were present not only in the blood of workers, but in that of wildlife and the general population as well. In 1999, researchers analyzed blood samples from 600 adults and an equal number of children. All of the samples, obtained randomly from blood banks and universities, contained traces of PHOs. But 3M continues to maintain that the chemicals pose no significant risk to consumers. “The levels that have been found in people and wildlife have never been associated with any adverse health or biological effects,” says Larry Zobel, the company’s medical director.

Still, evidence that has emerged over the past year suggests that perfluorochemicals are more dangerous than 3M has publicly acknowledged. The company has informed the Environmental Protection Agency that an unusually high number of its workers in Decatur have died of bladder cancer. An EPA hazard assessment dated August 31, 2000, notes that humans can orally absorb PHOs, which has a half-life of about four years. PHOa has induced tumors in the testes of rats and liver damage in both rats and monkeys.

Scientists are uncertain precisely how the substances have become so ubiquitous in people and animals. “To this day, we don’t know,” says Zobel. Researchers speculate that as perfluorochemicals degrade, millions of people may be absorbing the compounds each day through contact with carpeting, clothing, and furniture treated with Scotchgard, and from industrial waste discharged from factories that produce Teflon.

Company documents show that DuPont, which has long relied on 3M as a source of PHOa, was concerned enough about the chemical’s potential cancer-causing properties to search for a substitute. A 1993 DuPont memo, for example, heralds the discovery of a possible alternative to PHOa that was “between 32 and 53 times less bioaccumulative in the liver of male mice.” A 1994 missive expresses concern that “we may have a product stewardship issue if we have a [Teflon] finish that contains a suspect carcinogen.” And a 1996 memo says, “The worst case scenario is that [PHOa] could be classified as a large ‘C’ carcinogen.”

Rather than make such information public, DuPont has tried to silence its critics. Wilbur and Sandra Tennant, who own a farm near DuPont’s plant in Parkersburg, blame well-documented PHOa discharges into the groundwater for the demise of hundreds of their cattle. On March 6, the EPA received a letter from the Tennants’ attorney, Robert Bilott, asking the agency to “order DuPont to immediately cease all manufacturing activities” involving PHOa. Learning that Bilott intended to make a similar appeal at an EPA hearing on March 27, DuPont sought a temporary restraining order, complaining to U.S. District Judge Joseph Goodwin that such a presentation could generate “intense media coverage” and prejudice a jury in the Tennant case. John Tinney, an attorney for DuPont, bluntly characterized the risk to the company. “The court need look no further than the movies for practical application,” he told Goodwin, citing “the enormous success at the box office of Erin Brockovich and A Civil Action.” The judge refused to issue the restraining order; Bilott spoke at the hearing, but failed to generate the media attention DuPont feared.

3M will continue to make Scotchgard using other compounds, but its decision to phase out production of perfluorochemicals by the end of next year has left DuPont and other companies scrambling to find a new supplier. It has also forced the EPA to take a closer look at what may be a huge new class of toxics.

“They have a real potential for building up in the environment on a large scale,” explains Charles Auer, the director of the Chemical Control Division of the EPA’s Office of Pollution Prevention and Toxics. Last October, the agency announced that it may restrict the use of PHOs. In Canada, environmental regulators are rushing to perform risk assessments on 159 members of the chemical familyÑan effort that they call a “top priority.”

As scientists begin to appraise the damage done by products such as Scotchgard, environmental and consumer advocates are raising questions of corporate liability. “Let’s get this straight,” says Jane Houlihan, research director at the Washington-based Environmental Working Group, which has been reviewing Scotchgard-related data. “Twenty-five years ago, 3M and DuPont understood the unique persistence and toxicity of these chemicals. Now, in an act of ‘corporate citizenship,’ 3M is withdrawing some of them from production. For this we should thank them?”


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