Tijdschrift Voor Psychiatrie · 2026
Lithium in tap water: toxic or healthy?
By Hendriks SM, de Groot C
BACKGROUND: Dutch water companies are concerned about the high and rising levels of lithium in the river Rijn because of the possible harmful effects for the human body. AIM: To gain understanding in how lithium in drinking water effects human well-being. METHOD: Literature research for associations of lithium in drinking water. RESULTS: Despite the fact that lithium levels in the Rijn are rising, the amount seems to be negligible compared to a therapeutic dose of lithium carbonate. Ecological studies show that high levels of lithium in drinking water are possible associated with lower suicide and crime rates, lower incidence of dementia and lower prevalence rates of psychiatric admission and drug use. However, other studies showed negative associations for thyroid function and calcium homeostasis. CONCLUSION: Although the lithium concentration in drinking water appears to be low, there are scientific studies which show associations for lithium and health effects. However, limitations of ecological studies are that they are observational, are subjected to ecological bias, and that controlling for confounders is limited. Furthermore, other sources of lithium exposure, such as food intake, were not taken into account. Clinical studies are therefore necessary to confirm these outcomes.