Exposure to flame retardant chemicals called <"http://www.yourlawyer.com/practice_areas/toxic_substances">PBDEs (polybrominated diphenyl ethers) could have an impact on female fertility, according to a report just published in Environmental Health Perspectives. Researchers at the University of California, Berkeley found that women with higher blood levels of PBDEs were 30 to 50 percent less likely to become pregnant in any given month than women with lower levels.
PBDEs have been used in consumer products since the 1970’s, when new fire safety standards were imposed in the U.S. The chemicals are common in foam furniture, electronics, fabrics, carpets, plastics and other common household products. Animal studies have found that PBDEs can harm neurodevelopment, lower thyroid hormones and change levels of sex hormones. They can leach into the environment and be stored in fat cells. Dust containing PBDE’s has been found in homes, and studies have found that 97 percent of Americans have detectable levels of the chemicals in their blood.
Three PBDE’s – pentaBDE, octaBDE and decaBDE — have been developed for commercial use as flame retardants. PentaBDE and octaBDE have both been banned in several states but are still in products made before 2004. Last month, the U.S. Environmental Protection Agency announced that three major manufacturers of decaBDE will phase out this product by 2013.
To determine the impact PBDE’s might have on a woman’s ability to conceive, researchers at Berkeley measured PBDE levels in blood samples from 223 pregnant women who took part in a study at the Center for the Health Assessment of Mothers and Children of Salinas, which looked at environmental exposures and reproduction. Among these women, concentrations of PBDEs were slightly lower than in the general U.S. population, which could be attributed to the fact that many of the women grew up in Mexico, where exposure to the chemical is more limited.
Among women who were trying to become pregnant, those with high levels of PBDE in their blood were half as likely to do so in any given month. In fact, for every tenfold increase in blood levels of PBDEs, the odds of becoming pregnant were reduced 30 percent. Even after the researchers took into account other factors, such as exposure to pesticides, irregular menstrual cycles, frequency of intercourse, weight, use of birth control pills in the year before conception, smoking, and alcohol and caffeine use, the results were the same.
The study was limited to women who were “sub-fertile” and eventually did become pregnant. The researchers surmised that had they included infertile couples in the study, it is possible that they would have seen an even stronger effect from PBDE exposure.