Bromine (Br) exists in nature in the form of salts in seawater and underground deposits. Organic bromine compounds, which are created through chemical reactions in laboratories and factories, are used for a wide range of industrial purposes. Bromine is the key element in brominated flame retardants (BFRs). BFRs are used as flame retardants in many types of consumer products.
A type of BFR is polybrominated diphenylethers, or PBDEs. PBDEs have been in production since the 1970s and have been used heavily in the manufacture of furniture, textiles, and electronics. Two of the commercial formulations, known as pentaBDE and octaBDE, were phased out after a 2004 industry agreement. The third PBDE, known as decaBDE, is still used. Other common BFRs include Tetrabromobisphenol A (TBBPA) which is commonly used in plastics and circuit boards for electronics, but also in acrylonitrile butadiene styrene (ABS); and Hexabromocyclododecane (HBCD) which is used in extruded polystyrene for thermal insulation foams and is also applied in the back coating of textiles.
PBDEs are persistent toxic chemicals that build up in people and wildlife and contaminate breast milk and umbilical cord blood.
Depending on the form and level of exposure:
Studies in laboratory animals have found that PBDEs profoundly and permanently affect the developing brain at levels close to those in today's most highly exposed women (Ericksson 2001).
PBDE exposure may affect thyroid hormone, which is essential for proper brain development in the fetus (Zhou 2002).
PBDEs may also cause reproductive problems and birth defects (McDonald 2005).
DecaBDE, the most widely used form of PBDE, is classified as a "possible human carcinogen" by the U.S. Environmental Protection Agency (ATSDR 2015).
A 2005 study compared levels in people with those that cause toxic effects in laboratory studies, and found that approximately five percent of American women have levels that already exceed those that cause reproductive problems in laboratory animals (McDonald 2005).
ATSDR. Toxicological Profile for Polybrominated Diphenyl Ethers (PBDEs). Toxic Substances Portal (2015).
Darnerud, P. Toxic effects of brominated flame retardants in man and in wildlife. Environment International 29, 841–853 (2003).
Eriksson, P., Jakobsson, E. & Fredriksson, A. Brominated Flame Retardants: A Novel Class of Developmental Neurotoxicants in Our Environment? Environmental Health Perspectives 109, 903–908 (2001).
Mcdonald, T. A. Polybrominated diphenylether levels among united states residents: Daily intake and risk of harm to the developing brain and reproductive organs. Integrated Environmental Assessment and Management 1, 343–354 (2005).
Zhou, T. Developmental Exposure to Brominated Diphenyl Ethers Results in Thyroid Hormone Disruption. Toxicological Sciences 66, 105–116 (2002).
Published on September 22, 2016