The health of millions of people worldwide is negatively impacted by chronic exposure to elevated concentrations of geogenic fluoride in groundwater. Due to health effects including dental mottling and skeletal fluorosis, the World Health Organization maintains a maximum guideline of 1.5 mg/L in drinking water. As groundwater quality is not regularly tested in many areas, it is often unknown if the water in a given well or spring contains harmful levels of fluoride. Here we present a state-of-the-art global fluoride hazard map based on machine learning and over 400,000 fluoride measurements (10% of which >1.5 mg/L), which is then used to estimate the human population at risk. Hotspots indicated by the groundwater fluoride hazard map include parts of central Australia, western North America, eastern Brazil and many areas of Africa and Asia. Of the approximately 180 million people potentially affected worldwide, most reside in Asia (51–59% of total) and Africa (37–46% of total), with the latter representing 6.5% of the continent’s population. Africa also contains 14 of the top 20 affected countries in terms of population at risk. We also illuminate and discuss the key globally relevant hydrochemical and environmental factors related to fluoride accumulation.

全球数百万人的健康受到长期暴露于地下水中高浓度地源氟化物的负面影响。由于对健康的影响，包括牙齿斑点和氟骨症，世界卫生组织维持饮用水中 1.5 毫克/升的最大指导值。由于许多地区没有定期测试地下水质量，因此通常不知道给定井或泉水中的水是否含有有害水平的氟化物。在这里，我们展示了基于机器学习和超过 400,000 次氟化物测量（其中 10% > 1.5 mg/L）的最先进的全球氟化物危害地图，然后用于估计处于危险中的人群。地下水氟化物危害地图显示的热点包括澳大利亚中部、北美西部、巴西东部以及非洲和亚洲的许多地区。在全球可能受影响的约 1.8 亿人中，大多数居住在亚洲（占总数的 51-59%）和非洲（占总数的 37-46%），后者占非洲大陆人口的 6.5%。就风险人口而言，非洲还包含前 20 个受影响国家中的 14 个。我们还阐明并讨论了与氟化物积累相关的关键全球相关水化学和环境因素。