Potable reuse, the process of treating wastewater to drinkable standards, offers a reliable and sustainable solution to cities and regions facing shortages of clean water. However, implementation is hindered by perceptions of poor water quality and potential health threats. Herein, we compare water samples from potable reuse systems with conventional drinking waters based on the analysis of Chinese hamster ovary cell cytotoxicity contributed by disinfection by-products (DBPs) and sewage-derived anthropogenic contaminants. In all cases, the cytotoxicity of potable reuse waters is lower than that of drinking waters derived from surface waters. The median contribution to total cytotoxicity was 0.2% for regulated DBPs and 16% for the unregulated DBPs of current research interest. Nonvolatile, uncharacterized DBPs and anthropogenic contaminants accounted for 83% of total cytotoxicity. Potable reuse waters treated by reverse osmosis are not more cytotoxic than groundwaters. Even in the absence of reverse osmosis, reuse waters are less cytotoxic than surface drinking waters. Our results suggest that potable reuse can provide a safe, energy-efficient and cost-effective alternative water supply.
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In vitro bioassays for monitoring drinking water quality of tap water, domestic filtration and bottled water
Journal of Exposure Science & Environmental Epidemiology Open Access 16 June 2023
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The datasets generated and/or analysed during the current study are available in Supplementary Tables 1–8 for (semi-)volatile DBPs and in Supplementary Data 2 for the cytotoxicity bioassay results. Data associated with Supplementary Tables 1–12 are provided in Supplementary Data 1. Source data are provided with this paper.
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This work was supported by funding from the National Science Foundation (CBET 1706154 to W.A.M. and CBET 1706575 to M.J.P.) and the Water Research Foundation (projects 4737 and 5140) to W.A.M. and M.J.P.
The authors declare no competing interests.
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Supplementary Figs. 1–12, Tables 1–12, Notes 1–9 and references.
Supplementary Tables 1–12 in Excel format. Basic water-quality parameters, DBP concentrations, summary of cytotoxicity results and description of treatment processes.
Raw cytotoxicity data for each facility.
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Lau, S.S., Bokenkamp, K., Tecza, A. et al. Toxicological assessment of potable reuse and conventional drinking waters. Nat Sustain 6, 39–46 (2023). https://doi.org/10.1038/s41893-022-00985-7
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