Lithium levels in the public drinking water supply and risk of suicide: A pilot study.

Suicide is a major public health concern affecting both the society and family life. There are data indicating that higher level lithium intake with drinking water is associated with lower suicide rate. This pilot study examined the relationship between lithium levels in drinking water and suicide rates in Lithuania. Twenty-two samples from public drinking water systems were taken in 9 cities of Lithuania. The lithium concentration in these samples was determined by inductively coupled plasma mass spectrometry (ICP-MS). The suicide data were obtained from the Lithuania Database of Health Indicators, and comprised all registered suicides across all ages and gender within the 5-year period from 2009 to 2013. The study demonstrated an inverse correlation between levels of lithium (log natural transformed), number of women for 1000 men and standardized mortality rate for suicide among total study population. After adjusting for confounder (the number of women for 1000 men), the lithium level remained statistically significant in men, but not in women. Our study suggested that higher levels of lithium in public drinking water are associated with lower suicide rates in men. It might have a protective effect on the risk of suicide in men.