Former 3M Chemical Is WidespreadAug 15, 2004 | Star Tribune
Four years after 3M stopped making the chemicals behind such innovative products as Teflon, Scotchgard and Stainmaster, the compounds are showing up everywhere from remote Minnesota lakes to polar bears in Alaska and albatrosses in the Pacific Ocean.
The compounds, known as fluorochemicals, are a concern because they don't degrade and it's unclear how they spread. The U.S. Environmental Protection Agency is studying whether one of the compounds poses environmental or health risks, but it does not consider fluorochemicals harmful.
A steady stream of scientific studies in the past six years has reported low levels of the compounds in humans, foods and wildlife all over the world, including Great Lakes fish.
Now, in a study that underscores the pervasiveness of fluorochemicals, EPA-funded researchers at the University of Minnesota say they have detected traces of the compounds in two remote lakes in the Voyageurs National Park near International Falls, Minn. One lake is 11 miles from the nearest road.
3M, based in Maplewood, was a leading manufacturer of the compounds until 2000, when it stopped making, selling and using them and it reformulated Scotchgard because the compounds were so widespread. One of its big customers had been DuPont Co., which still uses a fluorochemical to make Teflon and other coatings.
Last week, DuPont denied charges by the EPA that for two decades it withheld health information that it was required to submit about one of the chemicals. The EPA is seeking fines that could total millions of dollars.
The study of Minnesota lakes was led by Matt Simcik, an assistant professor of environmental chemistry, who presented preliminary results at a scientific conference in May. Simcik said researchers also found the chemicals in two lakes in Tettegouche State Park near Silver Bay, Minn., in Lake Michigan and in the Minneapolis Chain of Lakes.
Researchers at the University of Iowa recently detected fluorochemicals in lakes Ontario and Erie. The study, published in June in the journal Environmental Science & Technology, said traces of the chemicals were found in all 16 samples taken.
"They are not high in a toxic sense," said Keri Hornbuckle, an associate professor of civil and environmental engineering at the University of Iowa. "There is no danger from exposure to the water, but they are high enough that they there is no question that animals are going to accumulate them from the aquatic food chain."
Hornbuckle said fluorochemicals are different from other persistent and highly toxic substances found widely in the environment. They include the banned pesticide DDT, the banned industrial oil/coolant mixture known as PCBs and mercury, a toxic element released by coal-burning power plants.
The spread of fluorochemicals is partly the result of consumer demand for stain-repellent carpeting, breathable waterproof jackets and nonstick cooking utensils. "We like these chemicals to keep the water off our back and to keep food from sticking on our pots," Hornbuckle said. "They are the result of our wealth."
Studies have suggested that 90 percent of Americans, including children, have the chemicals at low levels in their bodies. Yet scientists have not determined how they got into people.
A related mystery is how these chemicals are transported in the environment. Simcik said air currents may spread them, which would explain how they got into remote lakes. Another possibility, said Hornbuckle, is that the chemicals are washing off the stain-resistant or waterproof fabrics and ending up in wastewater discharges.
Few people have heard of these chemicals, which carry the almost unpronounceable names perfluorooctanoic acid (PFOA) and perfluorooctane sulfate (PFOS).
In 1945, chemical maker DuPont of Wilmington, Del., introduced Teflon, a product that over the next five decades would become a household name. Its use spread far beyond cookware to industries ranging from aerospace to computers. DuPont says such products can't be made without PFOA.
Seven years after Teflon's debut, Patsy Sherman, a chemist fresh out of college, was working for 3M in Minnesota on a substance to coat aircraft tires when a lab mishap helped launch another highly successful fluorochemical product Scotchgard fabric protector.
"I had made a sample of one of the fluorochemical rubbers," said Sherman, who retired in 1992 and now lives in Bloomington. "Another person to whom I had given it dropped it. It splashed it over brand-new tennis shoes. We tried to remove the fluorochemical using all the solvents we could find. Nothing would even wet these stains."
Many of the Scotchgard stain-repelling products relied on fluorochemical cousins of PFOS. For decades, 3M produced fluorochemicals at its plant in Cottage Grove and also in Decatur, Ala. 3M turned away from the chemicals, and ended production at the plants, in 2000. DuPont, which still needed PFOA for its coatings business, built its own manufacturing plant in North Carolina.
Since at least the mid-1970s, scientists have known that fluorochemicals end up in humans' blood. 3M's medical director Larry Zobel said the company began regularly testing fluorochemical workers in 1976 and has consistently found the chemical in their blood. Over the years, "we found no adverse health effects in our workers," he added. The workers were told of the results, 3M says.
Recent findings that three fluorochemical workers in a 3M Alabama plant died of bladder cancer a higher number than would be expected are being studied further, Zobel said. Production workers have 50 to 500 times more of the chemicals in their blood than the general population, he added.
The knowledge in the 1970s that fluorochemicals end up in humans did not trigger the kind of EPA review that has been taking place since last year. The process, called a risk assessment, could lead to regulations of PFOA.
The EPA last month charged that DuPont repeatedly failed to pass information about PFOA to the government, including data on the company's 1981 monitoring of pregnant workers at a West Virginia plant and the discovery of the chemical in one child's umbilical cord. The EPA is seeking millions of dollars in fines.
In a response filed Wednesday, DuPont said it wasn't required to submit the information and asked for a hearing. It said that PFOA found in the umbilical cord did not harm the baby. DuPont also is facing a class-action lawsuit by residents of a West Virginia community where PFOA has been detected in the water supply.
Chris Lagan, an EPA spokesman, said the DuPont information could have triggered an earlier EPA inquiry into the chemical. "Had we had that information, is it reasonable to say we would have acted sooner?" he said. "It is possible it [the current risk assessment] would have happened then."
3M has not been accused by the EPA of withholding information about the chemicals. The Minnesota Health Department said its tests of wells near 3M's Cottage Grove plant found no fluorochemicals.
Zobel of 3M said testing equipment improved in the 1990s, leading to the wave of reports by company researchers and others that fluorochemicals are widespread. The evidence prompted 3M to stop making and using the compounds, said Michael Santoro, 3M's director of regulatory affairs.
The expanding knowledge about fluorochemicals in the environment raises the question of how they could spread so widely before being comprehensively studied by federal regulators.
"We don't have a forward-looking system," said Timothy Kropp, senior scientist with the Environmental Working Group, a Washington, D.C., organization that has published EPA, 3M and DuPont documents on its Web site. "We have a backward-looking system. Something has to be a problem for EPA to look at it."