Strategies for Assessing and Mitigating the Impacts of Emerging Contaminants in Wastewaters

需要了解地表水沃茨中潜在有害物质的来源和分布情况，以保护人类健康和生态系统。为此，加拿大政府于2006年实施了化学品管理计划，以解决未评估化学物质的遗留问题，目标是大幅减少对人类健康和环境的风险。成千上万的物质需要评估，包括许多被归类为药物活性化合物（PhAC）的物质。尽管止痛药、抗生素和诊断剂等PhAC被设计为有益于人类健康，但它们在低剂量下刺激或阻断生理反应的能力在进入环境时可能会产生潜在的危险影响。然而，许多化合物在环境中的释放率、归宿、浓度和普遍性以及潜在影响方面缺乏数据。目前迫切需要为数以千计的现有物质以及今后将在加拿大制造或进口的物质建立接触模型。具体而言，需要采用简单有效的方法来评估释放到环境中的化合物的影响，并通过各种缓解办法，如升级水和废水处理系统或源头控制办法（例如分离、源头处理、消除或替代化合物），确定采取行动的优先次序。重要的是，考虑到促使使用这些药物的健康益处，必须以不仅考虑其环境后果而且考虑其社会和经济影响的方式评估缓解方案。因此，研究的目标是了解某一社区对某一物质或某一组物质的消费模式及其地表水浓度，以评估其对人类健康或水生物的潜在影响。这项研究将由6名研究生和10名本科生组成的小组进行，将包括以下内容：（1）根据其来源和使用率及其对环境和健康影响的潜力，将建立一个近500种PhAC的数据库;（2）将利用消费数据和人体代谢措施建立物质来源模型，以预测下水道的污染物负荷，废水处理厂和地表沃茨以及地表水的浓度;（3）将制定指标，根据化学品释放到地表沃茨的潜在影响对化学品进行评估和排序，并据此确定需要进一步研究或采取缓解措施的优先化学品;（4）将利用安大略和魁北克的人口信息和水文条件评估影响的地理分布;及（5）将探讨针对个别或类别PhAC的缓解策略，以尽量减少对环境和健康的影响。

An understanding of the sources and distribution of potentially harmful substances in surface waters is needed to protect human health and ecosystems. For this reason, in 2006, the Canadian Government implemented its Chemicals Management Plan to address the legacy of unassessed chemical substances with the goal of significantly reducing risks to human health and environment. Thousands of substances require evaluation including many classified as pharmaceutically active compounds (PhACs). Even though PhACs such as painkillers, antibiotics, and diagnostic agents are designed to be beneficial to human health, their ability to stimulate or block physiological responses at low doses can create potentially hazardous impacts when they enter the environment. However, data is lacking for many compounds in terms of their release rates, fates, concentrations and prevalence in the environment, and potential impacts. Exposure models are urgently needed for thousands of existing substances, as well as those to be manufactured or imported in Canada in the future. Specifically, simple and effective methods are required to evaluate the impacts of compounds released into the environment and to prioritize them for action through mitigation options such as upgrading of water and wastewater treatment systems or source control options (e.g. separation, treatment at source, compound elimination or substitution). Importantly, given the health benefits that motivate the use of these drugs, mitigation options must be evaluated in a manner that accounts not only for their environmental consequences but also their social and economic impacts. Therefore, the objective of the research is to develop an understanding of the consumption patterns in a community of a particular substance or group of substances and their surface water concentrations in order to assess their potential for human health or aquatic impacts. The research will be conducted by a group of 6 graduate and 10 undergraduate students and will comprise the following: (1) A database will be created of almost 500 PhACs based on their sources and rates of use and their potential for environmental and health impacts; (2) source models for substances will be developed using consumption data and human metabolism measures to predict contaminant loads to sewers, wastewater treatment plants and surface waters and surface water concentrations; (3) indicators will be developed to assess and rank chemicals according to their potential for impacts upon release into surface waters and, from this, priority chemicals for further study or mitigation will be identified; (4) the geographic distribution of impacts will be assessed using the demographic information and hydrological conditions for Ontario and Quebec; and (5) mitigation strategies will be explored for selected individual or classes PhACs in order to minimize environmental and health impacts.