Researchers from the U.S. Geological Survey (USGS) have published a study estimating lithium levels in groundwater across the United States, with implications for drinking water safety. The research, which involves DRI scientists Monica Arienzo and Daniel Saftner as coauthors, explores lithium concentrations in aquifers supplying both public and private wells.
Lithium is a naturally occurring element found in various environmental sources. While its presence has been linked to certain health benefits, such as reduced suicide rates and other mental health improvements, there are concerns about potential negative impacts like autism and thyroid issues. Despite these associations, data on lithium’s occurrence in drinking water remain limited.
The study highlights higher lithium levels in regions like Nevada and the Great Basin due to specific environmental factors. “This study complements our previous research (Arienzo et al., 2022; Saftner et al., 2023) that measured lithium concentrations, among other metals, in more than 250 privately owned domestic wells throughout the Great Basin,” said Saftner.
Saftner and Arienzo used their earlier findings to assess the accuracy of a national model predicting lithium levels in groundwater across the western U.S. This model aims to serve as a tool for safeguarding public health by highlighting areas with elevated lithium concentrations.
Melissa Lombard, USGS research hydrologist and lead author of the study, stated: “Lithium in well water has not been commonly monitored or measured in the U.S. in the past, and these new estimates and maps help fill the gap in that lack of information.” The findings can aid health researchers in exploring connections between low-level lithium exposure and human health outcomes.
Currently unregulated by federal standards, lithium is included on a list of unregulated contaminants monitored by public water systems according to recent EPA guidelines. The USGS study estimates that significant lithium levels occur predominantly across western states such as Montana, Wyoming, Colorado, Utah, Nevada, Arizona, New Mexico, Texas—and to some extent—in eastern regions.
The investigation focused on naturally occurring lithium resulting from geological processes. It noted that these natural concentrations are significantly lower than those found in pharmaceutical applications treating conditions like bipolar disorder.
Using data from 18,000 wells nationwide, researchers developed a machine learning model categorizing estimated lithium levels into four ranges based on observed samples: less than four micrograms per liter up to over 30 micrograms per liter.
USGS collaborated with partners from Desert Research Institute alongside public health experts at University of Toronto during this effort aimed at enhancing understanding around potential risks posed by elevated natural-lithium exposure through potable sources nationwide.
For further details about well-water testing procedures contact respective state-health departments directly while additional insights regarding publication may be accessed via Environmental Science & Technology journal archives or inquiries directed towards designated media contacts listed below:
Jessica Fitzpatrick
Public Affairs Specialist
jkfitzpatrick@usgs.gov
571-230-6681
Melissa Lombard
Research Hydrologist
New England Water Science Center
mlombard@usgs.gov
603-226-7816
