Boston, Massachusetts -- A study published online 18 June 2009 suggests that diet is an important route of exposure to polybrominated diphenyl ethers (PBDEs). PBDEs are a class of flame retardants that have been used in consumer products such as polyurethane foam, electronics and textiles, the report says.
PBDEs have not been used in new products in Europe and the US for some years now, although they are likely to be present in products still in use which were made before their use was phased out.
The study, by team from the Boston University School of Public Health, said that PBDEs have been measured in dust, air and both animal- and plant-derived foods.
And while dust has been thought to be the major route of exposure to PBDEs, this study suggests that diet may play a significant role. Serum levels of PBDE congeners were associated with consumption of fat from poultry and red meat but not with consumption of fish or dairy products.
It is not known how flame retardants get into commercial animal products, but the team suggests possibilities including contamination of animal feed, either during processing or packaging or by general contamination of the environment. PBDEs accumulate in fat tissue and resist degradation in the environment.
"Our study offers the first large-scale look at the effect of the American diet on PBDE body burdens showing significant associations with poultry and red meat consumption," the paper says. "As PBDE-containing products continue to degrade and enter the waste stream in larger amounts, future exposure to PBDEs may begin to shift more heavily from the indoor environment to the outdoor environment and, consequently, the diet."
According to the study, which will appear in the peer-reviewed journal Environmental Health Perspectives (EHP), PBDEs have been shown to cause adverse endocrine, neurological and hepatic effects in laboratory animals. Human studies to date suggest PBDEs may affect male development, reproductive hormones and fertility and thyroid hormone homeostasis.
The article is available free of charge at http://www.ehponline.org/members/2009/0900817/0900817.pdf.