Mike Moffatt considers how much it would cost to increase the lithium levels in drinking water, and how much might be gained as a result.
The city of Toronto has 3.3 murders/100,000 people (Source). A 30% reduction in this rate would lower it by 1 murder per year per 100,000 people. If our rough back-of-the-envelope calculations are correct and the lithium carbonate method works like the Texas study suggests, $153,000 buys us one less murder. That does not take into account the reductions in rapes, suicides, drug use or thefts.
Will it work? I don’t know. It seems like it would be worthy a pilot study or two. Although those levels of elemental lithium are believed to be safe, there may be side-effects we are not considering. There are ethical considerations as well, but it is hard to make a case that adding fluoride to the water supply is ethical but lithium is not – and we’ve been adding fluoride to drinking water for over half a century.