State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, 19 Xinjiekou Outer Street, Beijing, 100875, China; Science and Engineering Faculty, Queensland University of Technology (QUT), GPO Box 2434, Brisbane, 4001 Queensland, Australia.
Centre for Urban Research, School of Global, Urban and Social Studies, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia.
Environ Pollut. 2019 Dec;255(Pt 1):113217. doi: 10.1016/j.envpol.2019.113217. Epub 2019 Sep 9.
Urban stormwater reuse is becoming increasingly prevalent to overcome the serious urban water scarcity being experienced around the world. Therefore, the adoption of reliable approaches to minimise the human health risk posed by pollutants commonly present in urban stormwater such as heavy metals and polycyclic aromatic hydrocarbons (PAHs) is critical for safe stormwater reuse. This study collected a total of 40 pollutant build-up samples and analysed the concentrations of nine heavy metals and 15 PAH species. Based on pollutant build-up data, pollutant concentrations in stormwater were estimated through modelling. Risk assessment was conducted using an existing model developed by previous studies. The study outcomes confirmed that simply evaluating the individual pollutant concentrations based on guideline threshold values cannot comprehensively estimate the overall human health risk posed by these pollutants. Accordingly, it is recommended that the assessment of the overall human health risk should be based on the pollutant mix present as provided by the models discussed in this paper. The study also demonstrated the practical application of a robust risk assessment model to derive the hierarchy of hazard control to provide a reliable underpinning to urban stormwater risk management. The outcomes suggest that decentralised hazard control methods such as the provision of custom designed Water Sensitive Urban Design (WSUD) measures can be implemented in priority areas with high risk from stormwater pollution based on the risk assessment undertaken. Distributed hazard control methods can be applied to reduce the generation of primary toxic pollutants, especially chromium (Cr) and heavy PAHs, through elimination and substitution measures. The percentage reduction in traffic volume required to mitigate the human health risk can be quantified through the risk models presented. The study outcomes will contribute to the development of efficient, targeted and reliable stormwater management strategies and to identify viable opportunities for stormwater reuse.
城市雨水再利用正变得越来越普遍，以克服全球范围内严重的城市水资源短缺问题。因此，采用可靠的方法来最小化城市雨水普遍存在的污染物（如重金属和多环芳烃 (PAHs)）对人体健康的风险，对于安全的雨水再利用至关重要。本研究共采集了 40 个污染物累积样本，并分析了 9 种重金属和 15 种 PAH 物质的浓度。基于污染物累积数据，通过模型估算了雨水污染物浓度。风险评估采用了先前研究中开发的现有模型进行。研究结果证实，仅根据指导值阈值评估单个污染物浓度不能全面估计这些污染物对人体健康的综合风险。因此，建议根据本文讨论的模型提供的污染物组合进行整体人体健康风险评估。该研究还展示了稳健风险评估模型的实际应用，以确定危害控制的优先级，为城市雨水风险管理提供可靠的依据。研究结果表明，可以根据所进行的风险评估，在受雨水污染风险较高的优先区域实施分散式危害控制方法，如提供定制化的水敏性城市设计 (WSUD) 措施。分布式危害控制方法可用于通过消除和替代措施减少原生有毒污染物的产生，特别是铬 (Cr) 和重多环芳烃。通过所提出的风险模型可以量化减少交通量以减轻人体健康风险所需的百分比。研究结果将有助于制定高效、有针对性和可靠的雨水管理策略，并确定雨水再利用的可行机会。
