From: Robina Suwol
Date: 14 May 2004
Time: 08:02:44
Remote Name: 68.116.132.26
Dust full of toxic chemicals found all over houses
By JOAN LOWY
Scripps Howard News Service
11-MAY-04
Contamination from brominated flame retardants is so pervasive in American homes
that people cannot avoid exposure to the toxic chemicals, two new studies of
household dust found.
Studies by government scientists at the National Institute of Standards and
Technology and by the Environmental Working Group, an advocacy group that
researches toxic chemicals, found high levels of PBDEs (polybrominated diphenyl
ethers) in dust from 27 homes.
The studies raise new concerns about potential health risks to young children
because toddlers who crawl on the floor and put their hands in their mouths
generally have greater exposure to household dust than adults and because their
brain and organ systems are still developing.
The only study of PBDEs in children, done in Norway, found higher levels in
4-year-olds than in adults.
The new studies indicate household dust may be an important source of human
exposure to PBDEs, said Environmental Protection Agency scientist Linda Birnbaum,
an expert on brominated flame retardants.
Nevertheless, it is likely that food _ particularly fish _ is the chief source
of the PBDEs that wind up in people's bodies, Birnbaum said. That's because
PBDEs appear to act similarly to their chemical cousins, PCBs, which persist in
the environment for very long periods, accumulating in animal fat and working
their way up the food chain to top predators, she said.
PBDEs are a class of brominated flame retardants used in thousands of consumer
products, from computers to televisions to textiles to foam cushions. Laboratory
studies of mice and rats show that some of the most widely used PBDEs can
interfere with brain development and thyroid function.
Used extensively since the 1970s, PBDEs did not attract much attention until
1999, when Swedish scientists detected them in breast milk. Further studies
found that PBDE levels in women's blood and breast milk have been increasing
rapidly over the past three decades, especially in American women.
About 5 percent of women tested have been found to have PBDE levels near or
above the levels that have produced health effects in animal studies. Scientists
do not know how much exposure is dangerous for people, especially the developing
fetus, which is the most vulnerable.
The institute of standards study found high levels of PBDEs in dust samples
taken from 17 houses in the Washington metropolitan area. The levels of the
chemical components of deca, the most widely used of the PBDE mixtures, ranged
from 160 parts per billion to 8,700 ppb. Levels of penta, the second-most widely
used mixture, ranged from 200 to 25,000 ppb.
The working group's study found high PBDE levels in dust samples from 10 home
around the country. The average combined levels of deca, penta and octa _ a
third commercial mixture _ for nine of the homes was over 4,600 ppb.
All the homes in the working group's study belong to new mothers whose breast
milk was tested for PBDEs in an earlier study by the organization.
"Exposure to brominated fire retardants is unavoidable," the working group study
concluded. "(We) found them in the dust of every home and in the body of every
participant tested. ... Even if these toxic fire retardants were phased out
immediately, our exposures to them would continue through the foods we eat or
from the products in our households."
Institute chemist Heather Stapleton said PBDEs are so pervasive in most indoor
environments that she had trouble keeping her uncontaminated dust samples free
of the flame retardants.
Peter O'Toole, a spokesman for the Bromine Science and Environmental Forum, a
trade association for the brominated flame retardants industry, said the health
risk from household dust is "infinitesimal."
"These levels mean that one needs to eat over 10 pounds of dust per day before
seeing any effect," O'Toole said.
On the Net: www.ewg.org
(Contact Joan Lowy at LowyJ(at)SHNS.com. Distributed by Scripps Howard News
Service, http://www.shns.com)