Brominated Flame Retardants - Environmental Impact, Persistence and Biodegradability

Brominated flame retardants (BFRs) comprise a group of anthropogenic environmental contaminants. BFRs are used at relatively high concentrations in numerous applications, including the manufacture of electronic equipment, textiles, plastic polymers and in the car industry, primarily to protect materials against ignition. Due to the halogen(s) covalently bound to the carbon skeleton in BFRs, many of these compounds are toxic, persistent, have limited biodegradability and tend to bioaccumulate in the environment. Their widespread production and use, combined with inappropriate treatment of industrial wastewater and solid waste, are the cause of global environmental concern. Indeed, recent reports have demonstrated the presence of BFRs at various concentrations in air, water, soil, wastewater and sediments far from the locations where they are produced. Moreover, traces of BFRs have been detected in animals and humans. Cleanup of these contaminated sites by physicalchemical processes is expensive and labor-intensive and often results in shuffling toxicants from one site to another. One possible solution to this problem is intensive, targeted biological treatment. The main problem with a biological approach is the lack of knowledge concerning appropriate microorganisms, biochemical pathways and operational conditions facilitating biodegradation of synthetic chemicals at an acceptable rate. In this chapter, we will discuss the environmental impact, persistence and recent development in BFRs biodegradation research and the implication of such efforts on wastewater treatment processes.