Seattle, WA, Sept. 22--Chemicals used to prevent fires in everyday items such as furniture, carpet and computers--and known to cause developmental problems in test animals--have been measured in women's breast milk at troubling levels, says the first national study of the phenomenon, according to the Seattle Post-Intellgencer.
While emphasizing that mothers should continue to breast-feed their babies because of the many benefits of the practice, a study due out today warns that production and use of the chemicals should be discontinued.
Europe is phasing out the use of polybrominated diphenyl ethers, or PBDEs, and California recently passed legislation banning some forms of the chemicals, which came into heavy use in the 1970s.
The 14-state study by the Environmental Working Group, a research and advocacy organization, collected breast-milk samples in women from Seattle to Florida and Los Angeles to Boston.
While the study analyzed only 20 women's breast milk, the findings mirror earlier studies that involved larger numbers of women in select American cities. And one woman in the new study showed the highest level of PBDEs ever recorded in North America.
The study comes as concentrations of the chemicals--similar in many ways to the PCB fire retardants that have poisoned Puget Sound orcas and turned up in countless other animals, including people as far-flung as the Eskimos--appear to be increasing in Americans and their environment.
"It's indicative of the broken system of chemical regulation in the country," said Bill Walker of the Environmental Working Group, editor of the report. "The chemical regulation process in this country basically allows this grand experiment to be carried out on all of us. We release these chemicals into the environment and 20 or 30 years later we see the effects. That doesn't seem to make sense."
A representative of the Bromine Science and Environmental Forum, which represents the handful of companies that manufacture the flame retardants, said the industry is working on replacements for PBDEs considered most toxic. But, he added, the chemicals save hundreds of lives annually.
"When you say let's ban fire-retardants, you have to ask, well, what are you going to replace them with?" said Peter O'Toole, the forum's U.S. program director. "Are (the replacements) going to keep us safe, and are they as well-studied in terms of environmental effects?"
PBDEs are used in computer casings, carpets, marine lacquers and paints, fax machines, printers, cell phones, lamp sockets, circuit boards, coffee makers and other applications. The most troublesome form, scientists say, is in polyurethane foam used in items including furniture, mattresses, carpet padding and auto seats.
But it's unclear how the chemicals are moving from these products of the modern age into our bodies, scientists say. Many suspect that a lot of it comes in animal fat found in meat and dairy products, but recent studies have also found high levels in common house dust.
And here's the weird thing: Whether scientists look at blood or breast milk or fat or house dust, they find that a small proportion--from 3% to 16%, depending on the study--has especially high levels that can't be accounted for based on known exposure to products containing PBDEs.
In other words, people living in the same town and apparently doing a lot of the same things can have widely different PBDE levels--as much as a 50-fold difference.
"We're still trying to get a handle on why that might be," said Tom McDonald, a toxicologist with the California Office of Environmental Health Hazard Assessment.
"There's clearly something about this small fraction of the population that the sources of their exposures are different."
PBDEs' toxicity to humans remains unclear, though. The levels being measured in people are ten to 20 times less than levels shown to cause effects in laboratory mice and rats. While that might sound comforting, toxicologist McDonald is far from complacent. Put simply, he says, scientists probably aren't picking up effects on the lab rats at lower levels.
And bear in mind that levels in humans are increasing. That might translate into permanently depressed IQ levels in exposed children, for example, scientists say. Like PCBs, PBDEs hang around in the environment a long time. And they "bioaccumulate," meaning that each animal that eats a smaller animal containing the chemicals takes in a dose that is stored in its body rather than being excreted along with the rest of the prey animal. The chemicals build up to ever-higher levels.
Some researchers have taken to calling them "the new PCBs." Those chemicals, widely used as fire retardants in industrial equipment, were banned in this country in the 1970s. But everyone has some PCBs in them, and PBDEs appear to add to the harm.
The woman who provided a Seattle sample of breast milk is Erika Schreder, staff scientist at the Washington Toxics Coalition.
"It really brings it home to find out that what I hope is the best food for my baby has been contaminated by the chemical industry," Schreder said. "I wish that my breast milk was pure."
Her group was disappointed this year to see the Legislature pull financing for a Department of Ecology program aimed at phasing out chemicals such as PBDEs that accumulate in the environment and don't go away for a long, long time.
Renee Sharp, a scientist with the Environmental Working Group and co-author of the new report, pointed out that alternatives to PBDEs are available immediately.
Ikea, for instance, had to comply with the European ban on PBDEs that goes into effect next year, so the company simply used a thicker foam in its furniture that is still fire-resistant enough to meet safety standards, she said. Some computer manufacturers are starting to house their machines in metal instead of plastic.
