Researchers at Columbia University reviewed data from the Environmental Protection Agency related to "routine compliance monitoring records" between 2006 and 2011 of community water systems across the United States.
The goal of that review was to determine if the average concentration levels reported of various metals exceeded the maximum contaminant levels established by the EPA.
Those findings revealed "uranium is an under-recognized contaminant in CWS."
Uranium though, was not the only metal that the study, published this month in The Lancet examined. Also examined in the study were levels of antimony, arsenic, barium, beryllium, cadmium, chromium, mercury, selenium, and thallium. The data analyzed pertained to 37,915 community water systems which serve approximately 290 million people annually.
While detectable levels of uranium was found in 63% of the compliance reports, 2.1% of the community water systems reported an average that exceeded the maximum contamination levels allowable by the RPA.
While uranium is known to occur naturally in low levels in water and soil, the ramifications of detectable levels in the public water system can only be speculated.
"Previous studies have found associations between chronic uranium exposure and increased risk of hypertension, cardiovascular disease, kidney damage and lung cancer at high levels of exposure," Dr. Anne Nigra, an assistant professor of environmental health at Columbia University and one of the article's authors said.
The published objective of the study was to "estimate metal concentrations in community water systems across the USA, [and] to establish if sociodemographic or regional inequalities in the metal concentrations exist.
To that end, the study identified that the concentrations seemed most likely to occur in "semi-urban, Hispanic communities independent of region or location, highlighting environmental justice concerns."
The study was funded by the US. National Institutes of Health Office of the Director, US National Institutes for Environmental Health Sciences, and the US National Institute of Dental and Craniofacial Research.
Columbia University has provided interactive maps on their website.