This week's New York Times Magazine draws attention to an article in The British Journal of Psychiatry that has been the talk of bioethical circles since May, when researchers at Japan's Oita University reported that communities with increased levels of lithium in their drinking water suffered a significantly lower incidence of suicide. The Japanese data confirmed a previous study of drinking water in Texas that found a decreased incidence of both suicide and violent crime in counties with higher-than-average amounts of naturally-occurring lithium in the water. If these protective benefits are replicated -- and no equally deleterious health effects of such low-dose exposures are discovered -- public health authorities may soon confront the question of whether it is ethical to supplement all public water supplies with lithium.
The pioneering American psychiatrist Peter Kramer, best known for his work Listening to Prozac, first raised such a possibility at a conference in Germany earlier this year. Whether such a policy is justifiable will depend upon further study of risks and benefits. What is clear is that our society may soon stand on the brink of a public health revolution in which pharmaceuticals will be added directly to the water supply in order to further the common good.
The most well-known effort to fortify public water began in Grand Rapids, Michigan, on January 25, 1945, when H.Trendley Dean -- one of our nation's great unsuing heroes -- launched an effort to add fluoride to the drinking supply. Six decades later, Surgeon General Richard Carmona was able to write that "every $1 invested in fluoridation saves $38 or more in treatment costs" and that "fluoridation is the single most effective public health measure to prevent tooth decay and improve oral health over a lifetime, for both children and adults." The United States Centers for Disease Control and Prevention has declared the fluoridation of drinking water to be "one of ten great public health achievements of the twentieth century." That is not to say that fluoridation didn't have its opponents -- both mainstream dental scientists and an army of right-wing crackpots who viewed water fortification (and childhood vaccination) as part of a Marxist conspiracy. However, decades of evidence have proven them wrong. Our national dental hygiene is vastly improved from the pre-fluoride era, our water is no more expensive, and Soviet-style communism has not snatched away our liberty.
The benefits of lithium fortification may someday prove just as dramatic. Since the doses of lithium shown to be protective in both studies are magnitudes below the therapeutic levels used to control mood swings in bipolar disorder, the Japanese researchers suggest that lithium may prevent suicide through a different mechanism, possibly increasing the production neurotrophic factors that enhance connectivity among brain cells. At such low amounts, lithium is unlikely to produce the negative side effects -- hypothyroidism, nephrotoxicity, weight gain -- that complicate its use as a psychiatric drug. We should certainly make sure that these risks are minimal before tampering with the public water. At the same time, if low-dose lithium proves as good as its promise, we should not allow abstract arguments about our "freedom" to drink unadulterated water to prevent us from undertaking a mass fortification effort. If we are willing to ingest fluoride to prevent tooth decay, surely we can tolerate a trace of lithium to prevent suicides.
Lithium may actually be the tip of the fortification iceberg. The cholesterol-lowering agents known as statins might also be good candidates for inclusion in the water supply, particularly if data confirms that they increase life-expectancy in otherwise health individuals and if those susceptible to rare side-effects -- such as muscle breakdown -- could be identified in advance. The social and economic costs of supplying free bottled water to pregnant women, young children and potential side-effect victims might prove vastly lower than those of persuading all other adults to take a daily statin pill. Similarly, fortifying water with thiamine might prevent dementia in alcoholics.
Other possible agents are still in development. If researchers could effectively isolate a chemical that safely blocks pleasure pathways involved in the use of toxic substances, such as tobacco and cocaine, those blocking agents might also be added to the water supply. Preventing nicotine highs through such a novel distribution mechanism would save millions of lives annually. Each of these proposals, of course, should be evaluated on its own merits. Our society might decide that preventing suicide or cocaine addiction is worth such a mass medication effort, but lowering the cardiovascular disease associated with high cholesterol is not. What matters is that our society approaches these questions rationally and democratically, adopting the policy positions that will reduce human suffering and save the most lives possible. Knee-jerk appeals to irrational passions should have no place in this debate.
Some nay-sayers will inevitably argue that medically fortifying the public water is a violation of individual liberty. Of course, nobody is forcing those dissident individuals to drink tap water. They are welcome to purchase bottled water, as do a few hold-outs who still fear the pernicious effects of fluoride, or to dig their own wells. (These critics could learn a lesson from existing traditionalists: The Amish, for example, do not question the majority's right to use electricity, even though they prefer to light candles.) The difference between adding lithium to water and iodizing salt is a matter of degree, not of kind. From a libertarian perspective, the public ought to be informed which pharmaceuticals have been added to the water and should choose what to imbibe accordingly.
Unfortunately, some opponents will likely attempt to hold the public water hostage, arguing that because drug-free water is natural, is it somehow better. However, if the vast majority of people gain health benefits from fortifying the public water, and particularly if these benefits are life-saving, then there is nothing unreasonable about placing the burden not to drink upon the resistant minority. One person's right to drink lithium-free water is no greater than another's right to drink lithium-enhanced water. As long as the negative consequences or inconveniences are relatively minor, water fortification seems to be one of those cases where the majority's preference and interest should prevail.
Time will reveal whether lithium is indeed the next fluoride. Far more important is the revolutionary prospect of harnessing the common water supply to deliver life-saving and health-enhancing therapies to the public at low cost. The water belongs to the public, after all, and should be used for the collective good. As someone who treasures my freedom immensely -- including, I should emphasize, my inalienable right to commit suicide -- I look forward to the day when I can sacrifice whatever specious "liberty" claim I might have in consuming "natural" tap water in order to help save the lives of my neighbors and fellow human beings.