Polychlorinated diphenyl ethers (PCDEs) used commonly to be applied as flame retardants in furniture, carpets and other household products.  These chemicals have been banned because they have been found toxic.  The flame retardants commonly used now are polybrominated diphenyl ethers (PBDEs) because they were deemed to be safe.  Some PBDEs have recently been found toxic too and thus banned already from being used as flame retardants even though some other types still remain in use.

A new study conducted at Harvard T.H. Chan School of Public Health reveals that women with high levels of PBDEs in their blood were at higher risk for having thyroid diseases including hyperthyroidism, hypothyroidism, goiter, or Hashimoto's disease. The risk was even higher in postmenopausal women.  Somehow, the flame retardants have less an impact on the thyroid functions in men.  PBDEs like PCDEs are endocrine disrupting chemicals that persist in our bodies and the environment.   They can interfere with hormone functions.

The data used for the study came from the National Health and Nutrition Examination Survey (NHANES) in which blood samples were drawn in 2003 to 2004.  It should be noted that some types of PBDEs have been banned ever since.  So how the PBDEs currently used as flame retardants in furniture and carpets would affect the hormone/thyroid function remains unknown. 

The study was published in the journal Environmental Health.  (David Liu)