Small study finds two-thirds drop in blood concentrations of polybrominated diphenyl ethers

A ban on a class of persistent flame retardants in California a decade ago is already reaping benefits. Scientists found that levels of the outlawed polybrominated diphenyl ethers (PBDEs) in the blood of pregnant women fell by two-thirds in just three years.

PBDEs are commonly used in electronics and furniture to prevent fires. However, studies have linked PBDEs with learning difficulties and lower IQs in children exposed to higher levels of these chemicals in utero. People are principally exposed to PBDEs through their diet, where dust containing these chemicals, which has worn off of household goods, makes its way into food. As a result of greater regulatory scrutiny of flame retardants industry is now rushing to create new ones.  

The small study, conducted by US and Swedish researchers, compared the levels of PBDEs in 25 expectant mothers who came into the hospital in 2008–2009 with 36 who came in just three years later. In 2008–2009, researchers found that all the expectant mothers had detectable levels of five different PBDEs. In 2011–2012 only one of these PBDEs was found in all the blood samples tested.