Brominated fire retardants.

• Author: Pennybacker, Mindy
• Position: Green Guidance - Polybrominated diphenyl ethers

For those unmotivated by the threat of obesity, there's a new reason to get up off the couch and eat less fatty foods: Fire retardants used in polyurethane foam furniture have been linked, in experiments with rodents, to endocrine disruption and damage to developing nervous systems. Known as polybrominated diphenyl ethers, or PBDEs, these chemicals stick around in the environment and accumulate in animal fats. So, what we eat is one likely source of exposure--but where we sit may be another. In humans PBDEs are appearing in increasingly high levels, according to four studies by researchers at the Environmental Working Group, University of Texas, Indiana University, and California Dept of Toxicology and published in 2002. The neurological impact on children exposed in utero is of particular concern, researchers say.

In the Indiana study of American mothers and infants, accumulations of PBDEs in breast milk and blood were from 20 to 106 times higher than those found in a similar Swedish population. PBDEs have also been found in blood and breast milk in women in Japan, Germany, and Canada. What's especially alarming, researchers say, is that PBDEs are molecularly similar to PCBs, chemicals that have been shown to cause brain and nervous system in children whose mothers are contaminated fish. Though banned in 1978, PCBs still persist in the environment, and fish remain a potent exposure path. In a worldwide dispersal pattern akin to that of PCBs and DDT, PBDEs have been measured in San Francisco Bay fish and harbor seals, Greenland fish and mussels, Great Lakes gulls, Lake Ontario trout, polar bears near the North Pole, ringed seals from the Canadian Arctic, and beluga whales near Baffin Island. A 2001 University of Wisconsin study of salmon from Lake Michigan found some of the highest levels of PBDEs ever reported. Lower levels of PBDEs have been found in chicken and other meat.

Besides food, the other significant exposure routes are most likely house dust and air contaminated by PBDEs released from couches and other everyday consumer products. In addition to polyurethane foam furniture and mattresses, PBDEs are used in plastic casings for computers and other office machines, televisions, hair dryers, industrial textiles, and carpet pads.

U.S. body concentrations are by far the...