Efficient remediation of river sediments contaminated by polychlorinated biphenyls and hexachlorobenzene by coupling in situ phase-inversion emulsification and biological reductive dechlorination
Efficient remediation of river sediments contaminated by polychlorinated biphenyls and hexachlorobenzene by coupling in situ phase-inversion emulsification and biological reductive dechlorination
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DOI：
10.1016/j.ibiod.2019.02.007
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发表时间：
2019-05
影响因子：
4.8
通讯作者：
Shu-Chi Chang;C. Yeh;Szu-Kuang Lee;Tzu-Wen Chen;L. Tsai
中科院分区：
文献类型：
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作者：
Shu-Chi Chang;C. Yeh;Szu-Kuang Lee;Tzu-Wen Chen;L. Tsai
台湾的沉积物污染是一个严重的环境问题，因为它通过食物链和当地生态系统威胁人类健康。台湾南部的二仁河（ERR）是污染最严重的河之一，其沉积物已被疏水性有机化合物（HOC）严重污染。在所有 HOC 中，多氯联苯 (PCB) 的检测含量很高，而六氯苯 (HCB) 的检测频率最高。由于其较高的 Kow 值和较低的生物降解性，它们可以通过营养级进行生物放大，从而对人类和生态系统构成高风险。本现场研究旨在展示一种通过原位反转乳化和生物还原脱氯（ISPIE/BiRD）耦合对 Aroclor 1254 和 HCB 污染的沉积物进行有效修复的技术。通过使用含有风化污染物和新添加污染物的真实污染沉积物，一次 ISPIE 操作可分别去除约 62% 和 60% 的风化 Aroclor 1254 和 HCB。对于风化的 HCB 和 Aroclor 1254，70 天内的总去除率可高达 98%。宏基因组结果表明，ISPIE过程中的热选择显着改变了微生物群落的多样性和物种均匀度，并且脱卤球菌与PCB去除率不呈正相关。相反，耐热古菌（Methanosaetaspp.）可能在随后的生物脱氯中发挥更重要的作用。这些结果有力地支持了 ISPIE/BiRD 在全面的现场修复方面高度可行，并且这种新的微生物群落可能成为 HOC 污染沉积物生物修复的高效工具。
Sediment contamination in Taiwan is a critical environmental problem because it threatens human health through food chains and the local ecosystem as well. Er-Ren River (ERR) in southern Taiwan is one of the most polluted and its sediments have been severely contaminated by hydrophobic organic compounds (HOCs). Among all HOCs, polychlorinated biphenyls (PCBs) have been detected at high levels while hexachlorobenzene (HCB) has been most frequently detected. Due to their higherKowvalues and lower biodegradability, they can be biomagnified through trophic levels and consequently pose high risks to humans and the ecosystem. This field study is to demonstrate an effective remediation technology on sediments contaminated by Aroclor 1254 and HCB by couplingin situphase-inversion emulsification and biological reductive dechlorination (ISPIE/BiRD). By using real contaminated sediment with weathered and freshly-added contaminants, a single ISPIE operation can remove about 62% and 60% of weathered Aroclor 1254 and HCB, respectively. For weathered HCB and Aroclor 1254, the total removal could reach as high as 98% in 70 days. Metagenomic results showed that heat selection during ISPIE significantly changed the diversity and species evenness of the microbial community and that theDehalococcoideswere not positively correlated with the PCB removals. Instead, heat-tolerant archaea,Methanosaetaspp., may play much more important roles in the subsequent biological dechlorination. These results strongly support that ISPIE/BiRD is highly feasible on a full-scale field remediation and that this new microbial consortium could be a highly effective tool for bioremediation of HOC-contaminated sediments.