Women with high levels of a common type of flame retardant in their blood took longer to become pregnant than women with low levels. PBDEs, or polybrominated diphenyl ethers are found in common household items including plastics, fabrics, carpets, insulated wires, and foam furniture.
Researchers at the University of California, Berkeley found that for each 10-fold increase in the concentration of PBDEs in the blood, a woman's odds of conceiving decreased by 30 percent. For women actively attempting to become pregnant, the odds of conceiving dropped by 50 percent in any given month.
"We aren't looking at infertility, just subfertility, because all the women in our study eventually became pregnant," the study's lead author, Kim Harley, adjunct assistant professor of maternal and child health and associate director of the Center for Children's Environmental Health Research at UC Berkeley's School of Public Health, said in a statement. "Had we included infertile couples in our study, it is possible that we would have seen an even stronger effect from PBDE exposure.
"There have been numerous animal studies that have found a range of health effects from exposure to PBDEs, but very little research has been done in humans," Harley said. "This latest paper is the first to address the impact on human fertility, and the results are surprisingly strong. These findings need to be replicated, but they have important implications for regulators."
Although there are 209 different mixtures for PBDEs, only three formulations � pentaBDE, octaBDE, and decaBD � were developed for commercial use as flame retardants. They became common in the 1970s when new fire safety standards were implemented throughout the United States.
The EPA banned two of the PBDE mixtures in 2005 (pentaBDE and octaBDE), and the third will be phased out in 2013.
"The good news is these chemicals have or are being phased out," Hardley told the San Francisco Chronicle. "The bad news is their legacy will continue because of their presence in a lot of items in our homes."
"Every month, it seems, there are new studies linking this class of chemicals to problematic health concerns," Judy Levin, pollution prevention coordinator for the Center for Environmental Health in Oakland, told the Chronicle. "A bigger question is why are chemicals allowed to be placed in commerce and into our bodies before their toxicity is fully understood?"
How can you avoid PBDEs? Use these tips from the Environmental Working Group: