Reduced fertility rates may be connected to flame retardant exposure

Polybrominated diphenyl ethers (PBDEs), flame-retardant chemicals commonly found in foam furniture, fabrics, and carpets as well as electronics and household goods, may contribute to some women’s difficulty in achieving pregnancy, according to researchers at the University of California at Berkeley.

PBDEs are known to leach out of the environment and accumulate in human fat cells. Previous studies have found PBDEs to be common in house dust, and estimates have suggested that 97% of US residents have measurable levels of the chemical in their blood. Although animal studies have associated the chemicals with impaired neurodevelopment, reduced thyroid hormones, and altered levels of sex hormones, their effect on fertility is unknown.

The California study measured PBDE levels in blood samples from 223 pregnant primarily Mexican immigrant women enrolled at the Center for the Health Assessment of Mothers and Children of Salinas, an agricultural community. Researchers controlled for exposure to pesticides, as well as variables known to affect fertility: smoking, menstrual regularity, pre-pregnancy body mass, use of oral contraceptives, frequency of intercourse, and consumption of alcohol and caffeine.

Women who had elevated blood levels of four PBDE chemicals were 50% less likely to become pregnant in any given month than women with lower levels.

The study was supported by the National Institute of Environmental Health Science, the U.S. EPA, and the Centers for Disease Control and Prevention.

Harley KG, Marks AR, Chevrier J, et al. Environ Health Perspect. 2010; Jan 26 (epub).