Bradley Paul M, Romanok Kristin M, Smalling Kelly L, Donahue Lee, Gaikowski Mark P, Hines Randy K, Breitmeyer Sara E, Gordon Stephanie E, Loftin Keith A, McCleskey Richard Blaine, Meppelink Shannon M, Schreiner Molly L
U.S. Geological Survey, Columbia, South Carolina, USA.
U.S. Geological Survey, Lawrenceville, New Jersey, USA.
Environ Sci Process Impacts. 2025 May 21;27(5):1368-1388. doi: 10.1039/d5em00005j.
Tapwater (TW) safety and sustainability are priorities in the United States. Per/polyfluoroalkyl substance(s) (PFAS) contamination is a growing public-health concern due to prolific use, widespread TW exposures, and mounting human-health concerns. Historically-rural, actively-urbanizing communities that rely on surficial-aquifer private wells incur elevated risks of unrecognized TW exposures, including PFAS, due to limited private-well monitoring and contaminant-source proliferation in urbanizing landscapes. Here, a broad-analytical-scope TW-assessment was conducted in a hydrologically-vulnerable, Mississippi River alluvial-island community, where PFAS contamination of the shallow-alluvial drinking-water aquifer has been documented, but more comprehensive contaminant characterization to inform decision-making is currently lacking. In 2021, we analyzed 510 organics, 34 inorganics, and 3 microbial groups in 11 residential and community locations to assess (1) TW risks beyond recognized PFAS issues, (2) day-to-day and year-to-year risk variability, and (3) suitability of the underlying sandstone aquifer as an alternative source to mitigate TW-PFAS exposures. Seventy-six organics and 25 inorganics were detected. Potential human-health risks of detected TW exposures were explored based on cumulative benchmark-based toxicity quotients (). Elevated risks ( ≥ 1) from organic and inorganic contaminants were observed in all alluvial-aquifer-sourced synoptic samples but not in sandstone-aquifer-sourced samples. Repeated sampling at 3 sites over 52-55 h indicated limited variability in risk over the short-term. Comparable PFAS-specific for spatial-synoptic, short-term (3 days) temporal, and long-term (3 years quarterly) temporal samples indicated that synoptic results provided useful insight into the risks of TW-PFAS exposures at French Island over the long-term. No PFAS detections in sandstone-aquifer-sourced samples over a 3 year period indicated no PFAS-associated risk and supported the sandstone aquifer as an alternative drinking-water source to mitigate community TW-PFAS exposures. This study illustrated the importance of expanded contaminant monitoring of private-well TW, beyond known concerns (in this case, PFAS), to reduce the risks of a range of unrecognized contaminant exposures.
自来水（TW）的安全性和可持续性是美国的优先事项。全氟和多氟烷基物质（PFAS）污染因使用广泛、自来水普遍暴露以及对人类健康的担忧日益增加，而成为一个日益严重的公共卫生问题。历史上以农村为主、目前正积极城市化的社区依赖浅层含水层私人水井，由于私人水井监测有限以及城市化地区污染物源的扩散，面临包括PFAS在内的未被认识到的自来水暴露风险增加。在此，在一个水文脆弱的密西西比河冲积岛社区进行了一次分析范围广泛的自来水评估，该社区浅层冲积饮用水含水层的PFAS污染已有记录，但目前缺乏更全面的污染物特征描述以指导决策。2021年，我们在11个住宅和社区地点分析了510种有机物、34种无机物和3个微生物组，以评估（1）除已认识到的PFAS问题之外的自来水风险，（2）日常和逐年的风险变异性，以及（3）下层砂岩含水层作为减轻自来水PFAS暴露替代水源的适用性。检测到76种有机物和25种无机物。基于累积基准毒性商数（）探讨了检测到的自来水暴露对人类健康的潜在风险。在所有冲积含水层来源的综合样本中观察到有机和无机污染物的风险升高（≥1），但在砂岩含水层来源的样本中未观察到。在3个地点进行了52 - 55小时的重复采样，结果表明短期内风险变异性有限。空间综合、短期（3天）时间和长期（3年每季度一次）时间样本的PFAS特异性相当，这表明综合结果为长期了解法国岛自来水PFAS暴露风险提供了有用的见解。在3年期间砂岩含水层来源的样本中未检测到PFAS，这表明不存在与PFAS相关的风险，并支持将砂岩含水层作为减轻社区自来水PFAS暴露的替代饮用水源。这项研究说明了扩大对私人水井自来水污染物监测的重要性，除了已知问题（在本案例中为PFAS）之外，还能降低一系列未被认识到的污染物暴露风险。
