Effects of carbonaceous materials on microbial bioavailability of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in sediments

Abstract In this study, we investigated the influence of various types of carbonaceous materials (CMs) on the bioavailability of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) to polybrominated diphenyl ether (PBDE)-degrading microorganisms in CM-amended sediments. The microbial debromination ratio of BDE-47 was reduced by 92.8%–98.2% in the 5.0% CM-amended sediment compared with in sediment without CM amendment after 100 d of anaerobic incubation. The concentrations of lower brominated products also decreased when the content of CMs increased from 0.2% to 5.0%. The inhibitory effects of CMs on BDE-47 debromination were CM content- and characteristic-specific. The reciprocals of BDE-47 debromination ratios and lower brominated product concentrations showed positive linear correlations with CM contents in sediments ( p