A study on metal concentrations in U.S. community water systems (CWS) and patterns of inequalities, researchers at Columbia University Mailman School of Public Health found that metal concentrations were particularly elevated in CWSs serving semi-urban, Hispanic communities independent of location or region, highlighting environmental justice concerns. These communities had the highest levels of uranium, selenium, barium, chromium, and arsenic concentrations.
source https://www.lifetechnology.com/blogs/life-technology-science-news/uranium-detectable-in-two-thirds-of-us-community-water-system-monitoring-records