Microbial and Photolytic Transformations of Superfund Chemicals

该项目的广泛目标是阐明微生物和光解过程对目标超级基金化学品转化的单独和综合影响，应用于更好地了解现有超级基金场地的自然转化过程，并开发改进的补救系统。这些化学品将包括有机磷农药（毒死蜱、毒死蜱和二氮磷）和多环芳烃（芴及其杂环类似物咔唑、二苯并呋喃和二苯并噻吩;荧蒽和苯并[a]芘）。这项工作将产生重要的 它将提供关于影响自然系统中有毒物质接触的基本过程的信息，并将包括制定通过改进补救系统减少这些接触的新战略。该项目的具体目标如下。(1)评估个别目标超级基金化学品的单独光解和微生物分离转化。(2)确定光解和微生物转化对毒性的影响，并确定感兴趣的中间体。(3)评估光解中间体的生物降解性和生物降解中间体的光降解性。(4)评价物理、化学和生物因素对微生物和光解降解的影响，包括混合效应。 (5)开发和评估基于光解，氧化和微生物转化过程的创新组合的新型修复技术。这项工作将与本提案中的其他项目密切相关，其重点是相同的有机磷和多环芳烃，并通过使用其毒性测定来评估光解和微生物中间体的毒性。

The broad objective of this project is to elucidate the separate and combined effects of microbial and photolytic processes on transformations of target Superfund chemicals, with applications to gaining a better understanding of natural transformation processes at existing Superfund sites and to developing improved systems for remediation. These chemicals will include organophosphate pesticides (chlorpyrifos, parathion, and diazonon) and polycyclic aromatic hydrocarbons (fluorene and its heterocyclic analogs carbazole, dibenzofuran, and dibenzothiophene; fluoranthene; and benzo[a]pyrene). This work will yield important information regarding the fundamental processes affecting toxic exposures in natural systems, and it will include the development of new strategies for decreasing these exposures through improved remediation systems. The specific aims of this project are as follows. (1) Assess the separate photolytic and microbial isolate transformations of individual target Superfund chemicals. (2) Determine photolytic and microbial transformation effects on toxicity and identify intermediates of interest. (3) Assess biodegradability of photolytic intermediates and photodegradability of biodegradation intermediates. (4) Evaluate influence of physical, chemical, and biological factors on microbial and photolytic degradation, including mixture effects. (5) Develop and evaluate novel remediation technologies based on an innovative combination of photolytic, oxidative, and microbial transformation processes. This work will interface strongly with the other Projects in this proposal through its focus on the same OPs and PAHs, and through it's use of their toxicity assays to assess the toxicity of photolytic and microbial intermediates.