USGS maps lithium in groundwater

By Ellie Borst | 06/05/2024 01:39 PM EDT

A first-ever study from the U.S. Geological Survey found roughly 40 percent of groundwater contains lithium above EPA’s health reference level.

Water comes out of a faucet.

The U.S. Geological Survey assessed lithium levels in the nation's water supply. Steve Johnson/Flickr

The U.S. Geological Survey mapped for the first time which areas are potentially at high risk from groundwater containing lithium, a metal widely detected in drinking water and used in rechargeable batteries.

According to the recently published USGS-led study, a model predicted that about 40 percent of groundwater taken from wells, which covers roughly half of the nation’s water supply, contains concentrations of lithium above EPA’s health reference level.

How dangerous that is is still yet to be determined. EPA acknowledges there is “limited information available” about the health effects of lithium in water, let alone which concentrations could put health at risk. Lithium in drinking water is not federally regulated.


“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,” Melissa Lombard, USGS research hydrologist and lead author of this study, said in a statement.