Department of Civil and Environmental Engineering, Duke University, Hudson Hall, Durham, NC 27708, USA.
Nicholas School of the Environment, Duke University, 9 Circuit Drive, Durham, NC 27710, USA.
Water Res. 2018 Jan 1;128:102-110. doi: 10.1016/j.watres.2017.09.047. Epub 2017 Sep 30.
The increasing occurrence of tetrabromobisphenol A (TBBPA) in the environment is raising questions about its potential environmental health impacts as it has been shown to cause various deleterious effects in humans. The fact that the highest concentrations of TBBPA have been reported in wastewater sludge is concerning as effluent discharge and biosolids land application are likely a route by which TBBPA can be further disbursed to the environment. Our objectives in this study were to evaluate the effect of biochar (BC) and activated carbon (AC) in promoting the biodegradation of TBBPA, and characterize the response of anaerobic sludge microbial communities following amendments. Both carbonaceous amendments were found to promote the reductive debromination of TBBPA. Nearly complete transformation of TBBPA to BPA was observed in the amended reactors ∼20 days earlier than in the control reactors. In particular, the transformation of diBBPA to monoBBPA, which appears to be the rate-limiting step, was accelerated in the presence of either amendment. Overall, microbial taxa responding to the amendments, i.e., 'sensitive responders', represented a small proportion of the community (i.e., 7.2%), and responded positively. However, although both amendments had a similar effect on TBBPA degradation, the taxonomic profile of the sensitive responders differed greatly from one amendment to the other. BC had a taxonomically broader and slightly more pronounced effect than AC. This work suggests that BC and AC show great potential to promote the biodegradation of TBBPA in anaerobic sludge, and their integration into wastewater treatment processes may be helpful for removing TBBPA and possibly other emerging hydrophobic contaminants.
四溴双酚 A（TBBPA）在环境中出现的频率不断增加，引起了人们对其潜在环境健康影响的关注，因为它已被证明会对人类造成各种有害影响。事实上，TBBPA 的最高浓度已在废水污泥中被报道，这令人担忧，因为污水排放和生物固体土地应用很可能是 TBBPA 进一步扩散到环境中的途径。我们在这项研究中的目标是评估生物炭（BC）和活性炭（AC）在促进 TBBPA 生物降解方面的作用，并描述在添加这些物质后厌氧污泥微生物群落的反应。两种碳素添加剂都被发现可以促进 TBBPA 的还原脱溴作用。在添加了这些添加剂的反应中，几乎可以完全将 TBBPA 转化为 BPA，这比在对照反应中早了约 20 天。特别是，双溴代双酚 A 向单溴代双酚 A 的转化，这似乎是限速步骤，在添加任何一种添加剂的情况下都得到了加速。总的来说，对这些添加剂做出响应的微生物类群，即“敏感响应者”，在群落中只占很小的比例（即 7.2%），并且表现出积极的响应。然而，尽管两种添加剂对 TBBPA 的降解都有类似的效果，但敏感响应者的分类群特征在两种添加剂之间存在很大差异。BC 比 AC 的分类群影响更广泛且略为明显。这项工作表明，BC 和 AC 具有在厌氧污泥中促进 TBBPA 生物降解的巨大潜力，将它们整合到废水处理过程中可能有助于去除 TBBPA 和可能的其他新兴疏水性污染物。
