Brominated flame retardants: sources, distribution, exposure pathways, and toxicity

Brominated flame retardants (BFRs) are a relatively new generation of chemicals used as flame retardants in many types of consumer products. The most commonly used BFRs include tetrabromobisphenol A, polybromodiphenyl ethers, polybromobiphenyls, and hexabromocyclododecanes. Perhaps as a result of their widespread use and their lipophilicity, these compounds have become ubiquitous in the environment. This review summarizes BFR concentrations determined in different environmental media. The main sources of BFRs and the exposure pathways through consumption of contaminated food, ingestion, and inhalation of dust are reviewed. The distribution patterns in the abiotic and biotic environment as well as their toxicity are discussed with a view to provide a better understanding of these emerging environmental pollutants. In addition, it is envisaged that this review will heighten the importance of identifying emerging issues and data gaps, and generate a future research agenda on BFRs.