In a Oct. 13, 2005, photo, a physician's assistant at a hospital in… (Paul Sakuma / Associated…)
Pregnant California women have registered some of the highest levels of the toxic flame retardant PBDE in their bodies ever recorded worldwide, according to a new study released by researchers at UC San Francisco on Wednesday.
The research team tested 25 second-trimester pregnant women from Northern and Central California seeking care in San Francisco in 2008 and 2009 and found that their blood showed high levels of PBDEs, or polybrominated diphenyl ethers, which studies show are harmful to the liver, thyroid and nerve development, according to the study published in the Environmental Science & Technology journal.
Researchers believe that the women's high PBDE levels were due to California's strict flammability regulations enacted in the 1970s, which led manufacturers to add flame retardants to a wide variety of products, from electronics to furniture. The chemicals have largely been banned in California since 2004.
U.S.-born minority and low-income women were more likely to be exposed to the toxic chemicals, possibly because they were more likely to use secondhand furniture or live in low-income housing with poor ventilation, according to the study's lead author, Ami Zota, a postdoctoral fellow at UCSF's Program on Reproductive Health and the Environment.
Paradoxically, immigrant women from developing countries such as Mexico show lower levels of exposure to the chemicals, she said.
"What we've seen is if people are born outside of the U.S., like in Mexico, and migrate to the U.S., their exposures are already lower. The theory is Mexico used less of these chemicals so an immigrant's exposure in Mexico was lower than when they were in California," Zota said.
Zota said pregnant women can try to reduce their exposure by dusting and wet-mopping their homes, washing their hands frequently, and avoiding foam furniture and other products.
"Ultimately, it's very hard to avoid our exposures to these products because they're so widespread," Zota said. "We need policy measures."