On The Water Front.

Byline: editor: Abigail Walch

Bottled or tap, filtered or distilled--what's cleanest and greenest? Ginny Graves reports.

I am forever parched, especially when the weather turns balmy, and in my quest to quench my thirst I've gone from tap water to bottled--lured by adjectives like pure and pristine --and back again. (I eventually grew suspicious of the chemicals in plastic bottles and wary of their massive carbon footprint.) Then in March, news broke that much of the nation's drinking water contains traces of pharmaceuticals, which left me with a dilemma: What should I drink? Is pure water an oxymoron?

"There's no such thing as 100 percent pure. We can't even make it in the lab, because there's no technology that can totally remove contaminants, and even if we could it would become recontaminated as soon as it hit the air," says Christian Daughton, Ph.D., a scientist with the Environmental Protection Agency's National Exposure Research Laboratory in Las Vegas. Distilled is close, but doctors advise against drinking it, because it's mineral-free and leaches salt from the body.

Minerals I can tolerate, but Prozac? "The quantities are minute. We're talking parts per trillion," says Daughton.

Trouble is, no one knows how small a dose might have health effects, and given our society's fondness for meds, levels could get higher. Distasteful though it may be, some portion of the pills we take to calm our nerves, improve our moods, and prevent pregnancy winds up in the toilet. And in many areas that water, albeit carefully treated, is pumped back to the tap. But traces of drugs remain. While most experts aren't worried, some fear that chronic exposure to low levels of antibiotics and antibacterial soaps could add to the growing problem of resistant bacteria.

More troublesome are estrogen and its synthetic cousins, which many scientists blame for the recent appearance of circus-freak fish--males with eggs in their testes, for instance. "There's no doubt that rivers and lakes contain hormone levels that are affecting ...