Exposure to flame retardants linked to changes in thyroid hormones

Pregnant women with higher blood levels of a common flame retardant had altered thyroid hormone levels, a result that could have implications for fetal health, according to a new study led by researchers at the University of California, Berkeley.

A new study shows that PBDE flame retardants alter thyroid function in pregnant women.

"This is the first study with a sufficient sample size to evaluate the association between PBDE flame retardants and thyroid function in pregnant women," said the study's lead author, Jonathan Chevrier, a UC Berkeley researcher in epidemiology and in environmental health sciences.

"Normal maternal thyroid hormone levels are essential for normal fetal growth and brain development, so our findings could have significant public health implications.

These results suggest that a closer examination between PBDEs and these outcomes is needed."

PBDEs, or polybrominated diphenyl ethers, are a class of organobromine compounds found in common household items such as carpets, textiles, foam furnishings, electronics and plastics. US fire safety standards implemented in the 1970s led to increased use of PBDEs, which can leach out into the environment and accumulate in human fat cells.

Studies suggest that PBDEs can be found in the blood of up to 97 per cent of US residents, and at levels 20 times higher than those of people in Europe. Because of California's flammability laws, residents in this state have some of the highest exposures to PBDEs in the world.