INBRE-2 MICROBIAL DETOXIFICATION OF POLYCHLORINATED BIPHENYLS (PCBS) IN SOIL

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 多氯联苯（PCBs）是一种持久性有机污染物，可在食物链中生物累积，对人类健康构成威胁。在阿拉斯加，多氯联苯污染存在于许多以前使用的防御地点（FUDS），包括靠近温饱人口的偏远地区。传统的多氯联苯清除方法非常昂贵，特别是在偏远地区。另外，生物补救也是一种有吸引力的方法，可以使受多氯联苯污染的土壤解毒，减少人类接触。我们的主要目标是制定加速PCB解毒的战略，利用阿拉斯加本土植物促进土壤中PCB微生物降解的能力。先前的研究表明，某些植物可能会从其根部释放出二级芳香化合物，有效地促进根际多氯联苯降解细菌的长期生物刺激，这一过程被称为根际修复。已知阿拉斯加树种具有极高水平的芳香化合物，因此特别有希望促进多氯联苯污染场地的解毒，包括全州受污染的FUDS场地。使用微观研究和分子和培养为基础的微生物学技术，再加上密集的化学分析和建模，我们将评估不同的策略，加速微生物PCB解毒和减少PCB运输的潜力。将通过对多氯联苯进行化学分析，包括对共面二恶英类同系物和有毒对映异构体进行化学分析，然后根据确定的个别同系物和对映异构体的毒性当量因子计算多氯联苯毒性当量商数的变化，来评估毒性的降低。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Polychlorinated biphenyls (PCBs) are persistent organic pollutants that bioaccumulate in the food chain and pose risks to human health. In Alaska, PCB contamination is present in many formerly used defense sites (FUDS), including remote areas near subsistence-fed human populations. Conventional methods for PCB cleanup are extremely expensive, particularly in remote areas. Alternatively, bioremediation is an attractive means to detoxify PCB-contaminated soils and reduce human exposure. Our primary objective is to develop strategies for accelerating PCB detoxification that capitalize on the ability of native Alaskan plants to promote microbial PCB degradation in soil. Previous studies indicate that certain plants may release secondary aromatic compounds from their roots that effectively facilitate long-term biostimulation of PCB degrading bacteria in the rhizosphere, in a process known as rhizoremediation. Alaskan tree species are known to possess extremely high levels of aromatic compounds, and thus would be particularly promising for facilitating detoxification of PCB-contaminated sites, including contaminated FUDS sites across the state. Using microcosm studies and molecular and cultivation-based microbiological techniques, coupled with intensive chemical analyses and modeling, we will evaluate different strategies for accelerating microbial PCB detoxification and reducing potential for PCB transport. Reduction in toxicity will be evaluated using chemical analysis of PCBs, including coplanar dioxin-like congeners and toxic enantiomers, followed by calculations of the change in toxic equivalency quotient (TEQ) of PCBs based on the established toxic equivalency factor (TEF) of individual congeners and enantiomers.