The news of Prozac contaminating the UK's drinking water reminds me eerily of an old science fiction short story. I can't tell you which story exactly because my addiction to old science fiction anthologies coupled with a terrible memory for names and dates means that I've narrowed it down to a story that's probably from an anthology in the library at Sewanee. If you recognize it, please leave a note in the comments.

Anyway, the story goes like this:
A scientist goes to a small Texas town to figure out why their crime rate is the lowest in the country. He determines that the townsfolk's peaceful dispositions are caused by something in the water. He isolates the compound, tests it on monkeys, and determines that the miracle substance does indeed inhibit bellicose behavior.

Excited by the prospect of actually creating world peace, the scientist comes up with a plan to dump a large amount of the substance into a volcano which will soon erupt, spewing ash over most of the planet. He lets his brother in on the plan as an accomplice but tells no one else. The brother thinks the plan is a bad idea and refuses to help.

The scientist dumps the stuff into the volcano anyway and it erupts. For the next year or so, the world is calmer. Wars end, peace breaks out. However, during this time the scientist determines that the substance has a serious side effect, causing something like Alzheimer's.

Since the eruption, the scientist's brother has been drinking only bottled water and staying inside when it rains. But eventually, everyone else in the world succumbs to the side effects, even the scientist, so he is alone. He writes this story as his memoir and proceeds to drink the water.