Using triclosan and polyhalogenated dibenzo-p-dioxins to elucidate the importance of natural and anthropogenic sources of OH-PBDEs in fresh and estuarine waters

[arnold0967163] PI实验室最近的工作表明，在燃烧来源的二恶英减少的同时，令人惊讶的非燃烧来源的二恶英可能会增加：抗菌剂三氯生（及其氯化衍生物）和羟基化多溴联苯醚（OH-PBDEs）的转化。oh -多溴二苯醚是多溴二苯醚（PBDE）阻燃剂的降解产物，但也来自海洋系统中的天然来源。这项工作将继续他们对三氯生和羟基化多溴二苯醚（OH-PBDEs）的环境化学的研究，最终目标是评估由这些化合物形成的二恶英的环境意义。本提案的目的是通过实验室实验和实地测量相结合，确定人为和天然卤代羟基二恶英作为卤代二苯并对二恶英来源的重要性。这项研究将首次将实验室光解实验、废水分析和沉积物分析结合起来，开发并使用一套化学标记物，以揭示OH-PBDE以及通过OH-PBDE光解形成的pbdd是来自淡水和河口/海洋环境中的自然来源还是人为来源。实验室实验和废水样本分析将揭示人为来源的合适的OH-PBDE和PBDD标记物。对三氯生和三氯生衍生的二恶英水平和趋势的研究将为沉积物和沉积物岩心中oh -多溴二苯醚及其相关多溴二苯醚的比较提供另一套人为标记物。从这项研究中获得的知识将有助于评估废水中来自卤代羟基二苯基醚的多溴联苯和多氯联苯的来源和浓度。还将确定自然和人为来源的重要性，因为它们将确定与目标化合物的这些来源相关的“化学指纹”。如果认为有必要对卤代羟基二苯醚进行管制或进行额外的废水处理，则该信息至关重要。只有将实验室和现场测量结合起来，才能证实废水处理设施通过释放和随后的三氯生和oh -多溴二苯醚的光解作用，成为地表水中卤化二恶英的伪连续源。因此，拟议的研究将促进我们对废水衍生微污染物所带来的威胁的理解。这一知识对于目标化学物质尤其重要，因为已知母体化合物和预期的子产物都具有生物积累，在沉积物中持续存在，并具有不利的生物效应。这项工作的广泛社会效益将是全面评估卤羟基二苯基醚及其光解产生的二恶英对水生生态系统构成的潜在威胁，并确定这些化合物的自然和人为来源的作用。他们将通过参加明尼苏达大学理工学院探索职业项目来扩大未被充分代表的群体在科学和工程领域的参与，这是一个为期一周的非住宿暑期项目，面向9 -11年级的女孩和来自未被充分代表的群体的学生，并通过支持来自当地妇女的本科研究人员？圣本笃？年代的大学)。他们将通过项目的协作、跨学科和多机构性质建立研究基础设施和国际伙伴关系。最后，他们将通过明尼苏达州科学博物馆的互动活动、旧金山河口研究所的外联活动以及出版物和会议发言，广泛传播拟议的研究结果。

Arnold0967163Recent work from the PI's laboratories suggests that concomitant with the decrease of combustion-derived dioxins, there may be an increase in dioxins derived from surprising non-combustion sources: transformations of the antimicrobial triclosan (and its chlorinated derivatives) and hydroxylated polybrominated diphenyl ethers (OH-PBDEs). OH-PBDEs are degradation products of polybrominated diphenyl ether (PBDE) flame retardants, but also arise from natural sources in marine systems. This work will continue their study of the environmental chemistry of triclosan and hydroxylated polybrominated diphenylethers (OH-PBDEs), with the ultimate goal of assessing the environmental significance of the dioxins formed from these compounds. The objective of this proposal is to determine the importance of anthropogenic and natural halohydroxydiphenyl ethers as sources of halogenated dibenzo-p-dioxins using a combination of laboratory experiments and field measurements. This study will be the first to combine laboratory photolysis experiments, wastewater analyses, and sediment analyses to develop and use a set of chemical markers that will reveal whether OH-PBDEs, and the PBDDs formed via OH-PBDE photolysis, arise from natural or anthropogenic sources in both freshwater and estuarine/marine environments. Laboratory experiments and analysis of wastewater samples will reveal appropriate OH-PBDE and PBDD markers for anthropogenic sources. The studies on triclosan and triclosan-derived dioxin levels and trends will provide another set of anthropogenic markers to which OH-PBDEs and their associated PBDDs will be compared in sediments and sediment cores. The knowledge gained from this research will allow assessment of sources and prediction of concentrations of PBDDs and PCDDs that are derived from halohydroxydiphenyl ethers present in wastewater. The importance of natural and anthropogenic sources will also be determined, for they will identify the "chemical fingerprints" associated with these origins of the targeted compounds. This information is critical if regulation of halohydroxydiphenyl ethers or additional wastewater treatment is deemed necessary. Only with this proposed combination of laboratory and field measurements can it be verified that wastewater treatment facilities serve as a pseudo-continuous source of halogenated dioxins to surface waters via the release and subsequent photolysis of triclosan and OH-PBDEs. Thus, the proposed research will advance our understanding of the threats posed by wastewater derived micro-contaminants. This knowledge is especially important for the targeted chemicals, for both the parent compounds and expected daughter products are known to bioaccumulate, persist in sediments, and have adverse biological effects. The broad societal benefits of this work will be to provide a complete assessment of the potential threat to aquatic ecosystems posed by halohydroxydiphenyl ethers and the dioxins produced via their photolysis and to determine the role of natural and anthropogenic sources of these compounds. They will broaden participation of underrepresented groups in science and engineering by participating in the University of Minnesota Institute of Technology Exploring Careers program, a one-week non-residential summer program for 9th-11th grade girls and students from underrepresented groups and by supporting undergraduate researchers from a local women?s undergraduate institution (St. Benedict?s College). They will establish research infrastructure and an international partnership through the collaborative, interdisciplinary and multi-institutional nature of the project. Lastly, they will broadly disseminate the results of the proposed research via an interactive activity at the Science Museum of Minnesota, outreach activities of the San Francisco Estuary Institute, and via publications and conference presentations.