Women in four mountain villages in Argentina are ingesting so much lithium in drinking water they could develop metabolic disorders, Swedish researchers say.

Scientists at Lund University in Sweden say studies show the women are at risk of hypothyroidism, which can cause weight gain, fatigue, depression, sensitivity to cold and memory loss, a Lund release said Wednesday.

While lithium has established medical uses and is a common treatment for bipolar disorders, unregulated intake can cause problems, the Lund researchers said.

"The amounts of lithium that the Latin American women are ingesting via their drinking water are perhaps a tenth of what a patient would take daily for bipolar disorder," Lund occupational and environmental physician Karin Broberg said. "But, on the other hand, they are absorbing this lithium all their lives, even from before birth."

In an earlier study in which Broberg took part, involving the same mountain villages in the Salta province in Northwest Argentina, high levels of arsenic, lithium, cesium, rubidium and boron were found in the drinking water and in the urine of the women studied.

"Lifelong ingestion of arsenic and lithium brings a clear health risk. What the ingestion of the other substances implies is not known, because there is very little research on their role in ordinary drinking water," she said.