TUESDAY, March 22, 2005 (HealthDay News) -- Levels of flame retardants called PBDEs in blood samples taken from Americans have increased dramatically since the 1970s, while blood levels of dioxin and other persistent organic pollutants have declined, according to a new report.
Polybrominated diphenyl ether (PBDE) compounds are synthetic flame retardants used in many consumer products including fabrics, electronic equipment and Styrofoam. Each year, about 65,000 metric tons of PBDEs are made worldwide and much of that is used in North America.
Animals studies suggest PBDEs can cause a wide range of toxic effects. However, no studies have yet been conducted to assess the possible health effects in humans from exposure to these compounds.
Researchers measured levels of PBDEs in blood samples taken from Americans in 2003 and compared it to levels collected in 1973.
Overall concentrations of PBDEs were generally too low to measure in the 1973 blood samples, the researchers report. However, nearly all of the 2003 blood samples had significant levels of PBDEs.
Specifically, total blood PBDE levels in 2003 averaged 62 parts per billion -- about 90 times higher than levels collected in 1973.
The study, published in the March issue of the Journal of Occupational and Environmental Medicine, found that 2003 U.S. levels were the highest PBDE levels yet measured in any country.
PBDE concentrations in the U.S. blood samples were similar in all age groups, the researchers found. Women had higher PBDE levels than men, although the difference was not statistically significant. Increasing levels of PBDEs have also been found in recent samples of human breast milk.
There was some good news from the study: The researchers found that U.S. blood concentrations of dangerous persistent organic pollutants, such as dioxin and polychlorinated biphenyls (PCBs), have declined since 1973, probably as a result of bans on those substances.
More information
The U.S. Environmental Protection Agency has more about hazardous substances and their health effects.
