By: Nebraska Today
Photo: Craig Chandler | University Communication
Eight years ago, the data was sound but only suggestive, the evidence strong but circumstantial.
Now, DWFI Faculty Fellow Karrie Weber and colleagues, including Water Sciences Lab Director Dan Snow, have experimentally confirmed that nitrate, a compound common in fertilizers and animal waste, can help transport naturally occurring uranium from the underground to groundwater.
The new research backs a 2015 Weber-led study showing that aquifers contaminated with high levels of nitrate — including the High Plains Aquifer residing beneath Nebraska — contain uranium concentrations far exceeding a threshold set by the Environmental Protection Agency. Uranium concentrations above that EPA threshold have been shown to cause kidney damage in humans, especially when regularly consumed via drinking water.
“Nitrate isn’t always a bad thing,” said Weber, Both her previous research and some forthcoming studies suggest that nitrate mobilizes uranium only when the compound approaches its own EPA threshold of 10 parts per million.
“If we reflect upon what we published prior, that data suggests there’s a tipping point. The important thing,” she said, “is not to have too much.”