Flame-retardants (FR) are a group of anthropogenic environmental contaminants used at relatively high concentrations in many applications. Currently, the largest market group of FRs is the brominated flame retardants (BFRs). Many of the BFRs are considered toxic, persistent and bioaccumulative. Bioremediation of contaminated water, soil and sediments is a possible solution for the problem. However, the main problem with this approach is the lack of knowledge concerning appropriate microorganisms, biochemical pathways and operational conditions facilitating degradation of these chemicals at an acceptable rate. This paper reviews and discusses current knowledge and recent developments related to the environmental fate and impact of FRs in natural systems and in engineered treatment processes.
Halogenated organic compounds constitute one of the largest and most diverse groups of chemicals in the environment. Many of these compounds are toxic, persistent and, as a result of their often limited biodegradability, tend to bioaccumulate in the environment. Dibromoneopentyl glycol (DBNPG) and tribromoneopentyl alcohol (TBNPA) are brominated flame retardants commonly used as additives during the manufacture of plastic polymers and as chemical intermediates in the synthesis of other flame retardants. Both are classified as not readily biodegradable. In this paper, we demonstrate the biodegradation of both DBNPG and TBNPA by a common bacterial consortium under aerobic conditions in enrichment cultures containing yeast extract. DBNPG and TBNPA biodegradation is accompanied by a release of bromide into the medium, due to a biological debromination reaction. Molecular analysis of the clone library PCR amplified 16S rRNA gene was used to characterize the bacterial consortium involved in the biodegradation.
A unique miniature membrane bioreactor (mMBR) was designed and applied to examine the biodegradability of two complex organic compounds belonging to a family of brominated flame retardants (BFR) under continuous culture conditions using a bacterial consortium. BFRs are a widely used group of anthropogenic environmental contaminants. Many of these compounds are toxic, persistent, have limited biodegradability, and tend to bioaccumulate in the environment. Their widespread production and use combined with the inappropriate treatment and disposal of industrial wastewater have caused myriad global health and environmental concerns. Dibromoneopentyl glycol (DBNPG) and tribromoneopentyl alcohol (TBNPA) are aliphatic BFRs, classified as recalcitrant compounds, having half-lives of more than 100 years. Following successful debromination and complete biodegradation of the two target compounds in the mMBR, we used molecular and bioinformatic techniques to track changes in bacterial community composition during the biodegradation process.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.