It is one of the best-known chemical inventions of the 20th centur.
It is one of the best-known chemical inventions of the 20th century. Now, however, Teflon, the substance that stops food from sticking to pans, has been linked to hazards ranging from birth defects in people to the deaths of pet birds.
Chemical firms around the world are facing accusations that perfluorinated organic chemicals, such as perfluorooctanoic acid (PFOA), which is used to make Teflon and other oil- and water-resistant coatings, are a health threat.
The Case Against Teflon
In the highest profile case, chemical giant DuPont, the creator of Teflon, is due to face the Environmental Protection Agency (EPA) in the US courts. The EPA says that DuPont concealed its own 1981 research showing that its pregnant workers were passing the chemical to their unborn children. The EPA also states that in 1991 the company failed to report evidence from tests conducted from 1984 onwards showing that the chemical had contaminated the water supply across the river from DuPont's Teflon plant in Parkersburg, West Virginia.
DuPont has denied that it acted improperly. In an official response to the charges, Dupont senior vice-president Stacey Mobley said that "thorough and complete" responses to the EPA's charges were made and added: "We are confident that we have met all reporting obligations."
However, the Environmental Working Group (EWG), the Washington DC-based campaign group that first alerted the authorities to DuPont's tests, retorted that "DuPont answered the charges with redundant, illogical arguments that still skirt the question of why they failed to act in the first place."
If, as seems likely, DuPont and the EPA fail to reach an out-of-court settlement, the EPA will soon announce how much it intends to fine the chemical company. If the courts find against DuPont, the EPA could set a maximum fine of $313 million. Dr. Tim Kropp, senior scientist at EWG, said: "If they ask for anything like what they could ask for, this will be a landmark settlement. The EPA should force DuPont to pay a punishing fine such that it sends out a signal to all chemical manufacturers that it is not profitable to withhold critical information. No one has ever been fined more than $10 million before by the EPA, so this really is a big deal for the EPA, and they want to get it right. The EPA is keeping tight-lipped about its intentions."
The Risks of Nonstick
However, the controversy over the health risks of perfluorinated organic chemicals is not in doubt. "The Teflon chemical PFOA, like other fluorochemicals, is everywhere. It never breaks down in the environment and it's toxic at or near levels found in humans," said Dr. Kropp.
Bucky Bailey is a member of one of eight families living near the DuPont factory in Parkersburg, West Virginia, who are suing the company over the effects of PFOA. His mother, Sue Bailey, was a factory worker exposed to PFOA while pregnant. Mr. Bailey was born with only one nostril and other facial defects for which he has had 30 operations. He has recently married, but does not intend to have children in case they inherit his condition. He's determined to hold DuPont accountable. "I want them to admit that they made a mistake, to say they messed up and that they're going to do everything they can to help," Mr. Bailey said.
DuPont's Stacey Mobley responded: "Scientific evidence confirms that the trace amount of PFOA found in this one data point would pose no risk to human health."
Clifton Webb, DuPont's director of public affairs, also denied that his company had acted incorrectly. "We believe that we acted completely within the law, and we have the facts that will substantiate our position," he said.
Mr. Webb added that despite evidence of exposure in the womb and of water contamination, there was no evidence that actual harm resulted from PFOA exposure, and so the company was not legally bound to release its findings. "We stuck to the letter of the law," he said. "We have had 50 years of experience with PFOA and none of that experience suggests harmful effects resulting from exposure."
However, Dr. John Martin, an assistant professor of environmental analytical chemistry at the University of Alberta and one of the world's leading authorities on perfluorinated chemicals and their effects on human health, said it would be unwise to rule out the possibility of risks even at very low levels. Dr. Martin said: "I think we should be very concerned. The ability of PFOA to cause cancer in rodents doesn't necessarily mean that it can cause cancer in humans. But there are real concerns that it can affect the development of unborn children."
Toxic Fumes in Cookware
A separate health concern over Teflon is that when nonstick pans are overheated they release fumes that cause "Teflon flu." Mr. Webb said that the condition, which causes aches and chills, was "temporary and soon passes." Pet birds, however, are easily killed by the fumes. Retief Ehlers, a veterinary surgeon in London with a special interest in exotic birds, said: "Small birds such as budgies, finches, and cockatiels are particularly at risk."
Irene Clark, a bird owner in England, was at a loss to explain what had killed her pets in November 2004, but now it seems gases emitted from a Teflon baking tray were responsible. Although there have been no reported deaths when cookware has been used correctly, her four pet birds all died within hours of each other. Ms. Clark's vet told her that Teflon gas was probably to blame for their deaths.
DuPont's Mr. Webb responded by saying that the temperatures required to overheat Teflon pans would burn food, the fumes from which could also harm pet birds and humans. But it is the long-term effect on human health and the environment that most concerns scientists and campaigners.
Banning the Chemicals
Karine Pellaumail, a spokesperson for Friends of the Earth, said: "There are real concerns about the safety of these chemicals and, like all substances that persist in the human body and the environment, we would like to see them all phased out." Campaigners anticipate resistance to any attempt to ban perfluorinated polymers. Their unusual combination of properties water and oil resistance and near-imperviousness to heat means they're used in many consumer products and in a host of industrial settings.
In Europe, however, there are moves to outlaw perfluorooctane sulphonate (PFOS), one of the most notorious perfluorinated chemicals. In October 2004, the United Kingdom's then environment minister Alun Michael renewed calls for a unilateral ban on a potentially cancerous chemical used in industry and found in clothing, carpets, packaging, and household cleaners. The use of PFOS, which has been linked to instances of bladder cancer and defects in newborn children, is declining, but experts believe the risks can only be managed through legislation.
Mr. Michael said: "PFOS clearly meets the criteria for a chemical of high concern and presents a real and significant risk to the health of the population and the environment in the UK." The environment minister noted that use of the chemical had dropped significantly after it was withdrawn by the largest global producer, American company 3M. He warned, however, that PFOS continues to be used in industrial processes, chrome plating, fire-fighting foams, the photographic industry, semi-conductors, and hydraulic fluids in aviation.
The widespread use of perfluorinated chemicals also explains why it is so difficult to keep tabs on the exact sources of these pollutants. "We need a better understanding of exactly where they're all coming from," said perfluorinated chemical expert Dr. John Martin. However, such is their resistance to degradation that even if production stopped tomorrow, the chemicals will persist in the environment for hundreds, possibly thousands of years.
Evidence suggests that they are already ubiquitous pollutants. An international team of researchers reported in the September 2004 issue of Environmental Science and Technology that PFOA, PFOS, and related chemicals can routinely be detected in the blood of people in North and South America, Europe, and the Far East.
"We can even detect these chemicals in the middle of the Pacific Ocean - and if you think how much they're diluted in such a vast amount of water, it gives you an idea of how much of them there are in the environment now," said Dr. Martin.
According to Jane Houlihan, the vice-president for research at Environmental Working Group: "In retrospect, the use of perfluorinated chemicals may be seen as one of the biggest mistakes the chemical industry has ever made."