Investigation of the role of organic matter in partitioning of chemicals in the municipal wastewater treatment process

针对环境关注化学品急性和慢性暴露于环境中的潜在健康风险，环境关注化学品(CECs)的广泛使用和应用日益引起科学界、工业界、政府和公众的兴趣。CEC通过各种来源进入水环境，包括废水、农业和暴雨径流。其中，城市污水处理厂(MWTP)的污水是加拿大人持续存在的问题，这使得改善城市污水管理成为湖泊和河流可持续生态未来的关键因素。 CECs向有机质(OM)的分配对其在MWTP过程中的去向和运输非常重要，但在MWTP中的研究很少。有机质的分配历来是通过化学疏水性来描述的，而化学疏水性是通过辛醇-水分配系数包含在MWTP模型中的。然而，CEC包括物理化学性质差异很大的污染物，这些污染物可能不会根据疏水性进行分配。CEC分配行为的知识对于确定生物利用度和降解以及潜在的MWTP对环境的负荷至关重要，以评估新的和现有的化学物质对人类和环境健康的影响。 拟议研究计划的目标是对包括多溴二苯醚(PBDEs)、药品和个人护理产品(PPCP)和纳米材料(NMS)在内的CECs在MWTP过程中的去向和传输进行全面的基础和应用研究。该计划包括三个项目，目标是：(1)评估MWTP模型，以确定必要的物理化学参数和需要进一步了解的分配机制，以便为模型的改进和开发提供信息；(2)确定多溴二苯醚对不同MWPT OM大小部分的分配行为，以阐明分配机制并与各种物理化学参数相关联；以及(3)扩展为多溴二苯醚所获得的知识，以研究PPCPs和NMS，包括验证被动有机化学综合采样器。 从这项研究计划中获得的知识将是我们评估和描述CEC补救、制造和处置的潜在影响的关键组成部分，同时有助于开辟MWTP流程的新方法，帮助减轻CEC对接收环境的负荷。结果的潜在用户包括水和废水处理公用事业公司、环境保护机构、行业和政府决策者。模式改进也可用于加拿大和世界各地的MWTP，以帮助为更新治疗过程以保障环境健康的相关决定提供信息。

The widespread uses and applications of historic and newly emerging chemicals of environmental concern (CECs) is of increasing interest to the scientific community, industry, government and the general public in response to the potential health risks of acute and chronic exposures of CECs to organisms in receiving environments. CECs are introduced into aquatic environments through various sources including wastewater streams, agricultural and storm-water runoffs. Of these, municipal wastewater treatment plant (MWTP) effluents are a continuing issue for Canadians making the improvement of municipal wastewater management a critical element for a sustainable ecological future for lakes and rivers. Partitioning of CECs to organic matter (OM), is important in their fate and transport during the MWTP process, but has been poorly investigated in MWTPs. Partitioning to OM has historically been described via chemical hydrophobicity which has been included in MWTP models via the octanol-water partitioning coefficient. However, CECs include contaminants having widely varying physicochemical properties which may not follow partitioning based on hydrophobicity. Knowledge of CEC partitioning behaviour is essential for determination of bioavailability and degradation, and potential MWTP loadings to the environment for the assessment of new and existing chemical impacts on human and environmental health. The goal of the proposed research program is to conduct comprehensive fundamental and applied research on the fate and transport of CECs including polybrominated diphenyl ethers (PBDEs), pharmaceuticals and personal care products (PPCPs), and nanomaterials (NMs) in MWTP processes. The program includes three projects with objectives of: (1) Assessment of MWTP models to determine necessary physicochemical parameters and partitioning mechanisms needed to be further understood to inform model improvement and development; (2) Determine the partitioning behaviour of PBDEs to various MWPT OM size fractions to elucidate partitioning mechanisms and correlate to various physicochemical parameters; and (3) Extend knowledge gained for PBDEs to research PPCPs and NMs including validation of passive organic chemical integrative samplers. Knowledge gained from this research program will be a critical component in our ability to assess and delineate the potential implications of CEC remediation, manufacture and disposal, while helping to open new approaches to MWTP processes to help mitigate CEC loading to receiving environments. The potential users of the results included water and wastewater treatment utilities, environmental protection agencies, industry, and governmental decision makers. The model improvements may also be adapted for use in MWTPs, in Canada and worldwide, to help inform relevant decisions on updating of treatment processes to safeguard environmental health.