Flame Retardant Levels Decline in Pregnant Women in California

Following the statewide ban of a class of flame retardants a decade ago, researchers found a rapid decline of flame retardant levels in pregnant women's blood in California.

According to the study led by a team of researchers at UC San Francisco, a statewide ban on a class of flame retardants, associated with causing learning difficulties in children, led to a drastic decline in the levels of polybrominated diphenyl ethers (PBDEs) in the women. These chemical are known to persist in the environment for a very long time.

"We were pleasantly surprised by the extent of the decline. Regulations can have an impact on people's everyday lives," said Ami R. Zota, MS, an assistant professor of environmental and occupational health at the George Washington University School of Public Health and Health Services, and the study's lead author.

This study is the first to reveal the decline in PBDEs in people after the chemical was banned in California. The findings were based on the comparison of a group of 25 women who visited the hospital in 2008-2009 and another group of 36 women who visited the hospital during 2011-2012. The first group of 25 women had reported highest levels of PBDEs but the levels dropped by two third in just three years. Women tested from 2008-2009 had all five PBDEs in the blood, whereas during 2011-2012, the women had just one of the PBDEs. 

"What that means is that when California enacts the new flammability standard, there will be an opportunity for reductions in other flame retardants, many of which we may not even know about because there is a lack of data on their use and potential human health effects," Tracey Woodruff, PhD, MPH, the director of UCSF's Program on Reproductive Health and the Environment, and the study's senior author said in a statement.

Polybrominated diphenyl ethers- used as flame-retardant in foam furniture- have been linked to learning difficulties. Studies have claimed that pregnant women's exposure to even low levels of this chemical can trigger various difficulties in the offspring that vary from attention deficit, lower IQ to problems with concentration. They can alter the thyroid hormone in adulthood. The nursing mothers pass the PBDEs through breastmilk. 

The study is published in the journal Environmental Science & Technology.