Besides sulfate-induced diarrhea, recent studies have emphasized that groundwater sulfate drives the release of arsenic in groundwater and accelerates water pipeline corrosion. Despite its impact on public health and urban infrastructure, sulfate has been overlooked in water supply research. Here, we used a random forest model to develop a 1 km global map depicting the probability of sulfate exceeding 250 mg/L in groundwater based on the World Health Organization’s guidelines. The map was further applied to estimate the exposed population and identify contributors of sulfate exceedance in global hotspot regions. The results revealed that sulfate exceedance in groundwater was widespread in 156 countries. Approximately 194 million people use water with sulfate levels exceeding 250 mg/L. Among them, around 17 million people face groundwater sulfate concentrations surpassing 500 mg/L, with 82% of these individuals residing in ten specific countries. Contributing factor analysis in these countries indicates that annual precipitation and sedimentary rocks are the primary factors contributing to sulfate concentration prediction, while other natural and anthropogenic predictors exhibit region-specific impact patterns. This study uncovered a significant prevalence of elevated sulfate levels in groundwater, highlighting the need to integrate sulfate into water safety management practices.

中文翻译：

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了解地下水硫酸盐的全球分布并评估高危人群


除了硫酸盐引起的腹泻外，最近的研究还强调，地下水硫酸盐会促进地下水中砷的释放并加速水管腐蚀。尽管硫酸盐对公共卫生和城市基础设施有影响，但在供水研究中一直被忽视。在这里，我们使用随机森林模型开发了一张 1 公里的全球地图，根据世界卫生组织的指南描绘了地下水中硫酸盐超过 250 mg/L 的概率。该地图进一步用于估计暴露的种群并确定全球热点地区硫酸盐超标的贡献者。结果显示，地下水中硫酸盐超标在 156 个国家/地区普遍存在。大约 1.94 亿人使用硫酸盐含量超过 250 毫克/升的水。其中，约有 1700 万人面临地下水硫酸盐浓度超过 500 毫克/升的问题，其中 82% 的人居住在 10 个特定国家。这些国家/地区的贡献因子分析表明，年降水和沉积岩是影响硫酸盐浓度预测的主要因素，而其他自然和人为预测因子则表现出特定于地区的影响模式。这项研究揭示了地下水中硫酸盐含量升高的显著普遍性，突出了将硫酸盐纳入水安全管理实践的必要性。