Public health risk assessment of microbial contamination events in distribution systems: Impact of parameters and model construct

本研究计划的主要目标是开发一个基于定量微生物风险评估（QMRA）的模型，以评估与饮用水分配系统（DS）中微生物污染事件相关的公共健康风险，这些事件由（i）与低压条件相关的入侵，（ii）交叉连接和回流的污染，以及（iii）主要安装造成的污染，修复或修复的做法。需要这样的工具（i）为监管机构提供支持，制定与DS管理相关的指南或法规，以及（ii）为水务公司提供风险管理策略，以最大限度地减少公共健康风险，同时沿着对实际健康风险和昂贵的配电基础设施和运营升级的紧迫性的非常需要的答案。虽然这种模型的主要组成部分已经由候选人作为她在USEPA的博士后研究的一部分进行了布局，但该模型仅涉及与低压有关的入侵事件。关于污染物进入的估计以及归宿和迁移的模拟，已经确定了局限性，需要进一步的工作来广泛应用于各种DS配置。

The main goal of this research program is to develop a model based on quantitative microbial risk assessment (QMRA) to evaluate the public health risks associated with microbial contamination events in drinking water distribution systems (DS) resulting from (i) intrusion associated with low pressure conditions, (ii) contamination from cross-connections and backflow, and (iii) contamination due to main installation, repair or rehabilitation practices. Such a tool is needed (i) to provide support to regulatory agencies in developing guidance or regulations related to DS management, and (ii) to provide risk management strategies to water utilities in order to minimize risk for public health along with a very needed answer on the actual health risks and urgency of costly upgrades of distribution infrastructures and operations. While the main building blocks of such a model have been laid out by the candidate as part of her post-doctoral studies at USEPA, the model only addressed intrusion events related to low pressures. Limitations have been identified regarding the estimation of contaminant entry and simulation of fate and transport, and further work is needed for a widespread application to various DS configurations.