Identifying critical operational control points and strategies to minimize microbial risk during drinking water treatment

确定关键操作控制点和策略，以尽量减少饮用水处理过程中的微生物风险

• 批准号: 517704-2017
• 负责人: Emelko, Monica
• 金额: $ 6.72万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=692469
• 关键词: Identifying; critical; operational; control; points

Protozoan pathogens remain a significant public health threat associated with the provision of safe drinking water. Climate change is expected to exacerbate these risks due to increased frequency and intensity of extreme weather events. Most drinking water utilities reliant on surface water in North America utilize chemically-assisted filtration (CAF) as a key treatment process that is a required barrier to protozoan passage into treated drinking water supplies. Traditional monitoring strategies for treated water are ineffective at ensuring protozoan removal because 1) methods for the enumeration of protozoa are inadequate and 2) reliable surrogates for protozoan removal by CAF are not available. To protect public health from waterborne disease, traditional regulatory approaches have required specific equipment that is "well operated." Recently, the World Health Organization Guidelines for Drinking Water Quality (GDWQ) have recommended Water Safety Plans (WSPs) as a notably different, better, system-specific approach for managing pathogen risk in drinking water. Here, critical control points (CCPs) represent a point, step, or procedure at which control can be applied and, as a result, a water safety hazard can be prevented, eliminated, or reduced to an acceptable level. The development of a CCP-based approach for ensuring protozoan removal by CAF is proposed herein. The research includes the 1) integration of quantitative microbial risk assessment (QMRA) with the CCP-approach for minimizing protozoan passage through CAF and 2) development of an image analysis tool for rapid protozoan identification and enumeration. This work will help to advance protozoan pathogen risk management by CAF during drinking water treatment. It will contribute new knowledge, generate technological innovation, and train highly qualified personnel who can effectively apply emerging scientific tools for risk assessment to develop improved drinking water treatment strategies, technologies, and policies. The long-term benefits of this research include helping to reduce the societal costs of water-related illnesses and enabling innovative, water utility-specific WSPs and adaptation strategies in response to land disturbances and changing climate.

原生动物病原体仍然是与提供安全饮用水相关的重大公共卫生威胁。由于极端天气事件的频率和强度增加，预计气候变化将加剧这些风险。北美大多数依赖地表水的饮用水公用事业公司都采用化学辅助过滤 (CAF) 作为关键处理工艺，这是原生动物进入处理后的饮用水源所需的屏障。传统的处理水监测策略无法有效确保原生动物的去除，因为 1) 原生动物计数方法不充分，2) 没有可靠的 CAF 去除原生动物的替代方法。为了保护公众健康免受水传播疾病的影响，传统的监管方法需要“运行良好”的特定设备。最近，世界卫生组织饮用水质量指南 (GDWQ) 推荐水安全计划 (WSP) 作为一种明显不同、更好、针对特定系统的方法来管理饮用水中的病原体风险。这里，关键控制点（CCP）代表可以应用控制的点、步骤或程序，从而可以预防、消除水安全危害或将其降低到可接受的水平。本文建议开发一种基于 CCP 的方法，以确保 CAF 去除原生动物。该研究包括 1) 将定量微生物风险评估 (QMRA) 与 CCP 方法相结合，以最大程度地减少原生动物通过 CAF 的通道；2) 开发用于快速原生动物识别和计数的图像分析工具。这项工作将有助于推进 CAF 在饮用水处理过程中对原生动物病原体的风险管理。它将贡献新知识，产生技术创新，并培训高素质人才，使他们能够有效地应用新兴科学工具进行风险评估，以制定改进的饮用水处理战略、技术和政策。这项研究的长期好处包括帮助降低与水有关的疾病的社会成本，并实现创新的、针对水务公司的水安全计划和适应策略，以应对土地扰动和气候变化。