Lithium is the lightest metal in the world, and the least dense solid element. It is highly reactive, so is rarely found by itself in nature and is usually bound with other elements. As a psychiatric drug, it is bound as a salt and is most commonly found in the form of Lithium Carbonate (Li2CO3).
Lithium is found is most living organisms in small amounts and can even be found in some drinking water naturally (from volcanic rock). When ingested, it decreases norepinephrine release. Norepinephrine is the chemical most responsible for focused thinking, so decreasing it seeminly helps people stop focusing (which is why it's used to treat mania). Lithium also increases the synthesis of serotonin, which is responsible for producing feelings of well being (which is why it's used to treat depression).
From a logical perspective, it's a balancing drug. Humans, though, do not necessarily thrive in moments of middle ground. Sometimes the extremes are what propel us forward into the unknown, and potential greatness. So why dope the water supply?
Scottish researchers have found a correlation between suicide rates and natural lithium levels in the water supply, similar to studies in Japan and Austria. Of course, two pieces of information that correlate do not imply that one causes the other, and studies will need to take place to decide whether or not the lack of lithium really can lead to depression and suicide. One scientist involved has already received death threats.
Adding chemicals to public water supply is not uncommon. Water gets dirty, parasites, bacteria and other things can survive and so much of the municipal water supply is treated with chlorine as a cleaning agent. Some supplies are treated with fluoride to help mineralize teeth. The costs and benefits are both weighed and it is usually left up to the locality, as to what it wants to add to its water.
Accute and chronic lithium toxicity can be devastating. A list of side effects from the US National Library of Medicine include:
It is possible (and even likely) that small amounts of lithium are extremely good for the human body, but is dosing the water the right way to administer it?
Image credit: http://pixabay.com/p-84487/?no_redirect