Plastic Water Bottles: Should You Avoid the Disposable Kind, Too?

"Awwk!" That was my first reaction when I read a recent E-mail about new dangers lurking in my disposable water bottle, the one with a No. 1 recycling code stamped on the bottom that sits on my desk waiting to be refilled. There's a new study from Germany out today that tested the water in those bottles and found estrogenlike compounds, most likely leaching out from the plastic. These water bottles don't contain the notorious chemical bisphenol A, which is found in hard water bottles, baby bottles, and the plastic coatings of metal cans. (Studies of BPA indicate that high exposures could increase the risk of reproductive health problems and possibly breast, prostate, and ovarian cancers, which is why six leading baby bottle makers last week decided to ban it from their products.) The soft bottles do, though, contain other estrogenlike compounds, still unidentified, that could have the same harmful effects as BPA.

The researchers from Goethe University sampled 20 brands of bottled water packaged in plastic and glass bottles and found that 78 percent of the samples packaged in plastic bottles had high amounts of chemicals called "endocrine disrupters," compared with 33 percent of those bottled in glass. I was surprised to learn that even the spring water bottled in glass containers had these chemicals, so I called on an expert to tell me why. "Birth control pills, hormone therapy medications, and a host of contaminants can all get into our water supply, and we haven't figured out a way to affordably filter them out," explains Patricia Hunt, a geneticist and reproductive biologist at Washington State University who is well versed on the new study.

I was hoping she'd calm me down, but instead she got me a bit more nervous, thinking that there's simply no way to avoid endocrine disrupters in my beverages, short of living on freshly squeezed orange juice. Still, she says, it's a safe bet to say that drinking out of plastic water bottles is worse than drinking out of glass or metal ones. (She herself totes a metal canteen around with her for water on the go.) After all, the study also found that mollusks—yes, snails—reproduced more heartily when they were placed in water-filled plastic bottles as opposed to glass ones. "Who knew that mollusks love estrogen?" observes Hunt. "It's a truly interesting study." Sure, interesting. And scary? "Oh, yes, scary, too."

She's mostly, though, worried about the effects that these chemicals have on fetuses and newborns, whose organ systems haven't fully developed. Other endocrine disrupters called phthalates are commonly found in plastic toys. "Everything [infants] put into their mouths is plastic these days," she says. Except their thumbs? "Oh, yes, not those." Sort of makes me relieved that my three kids were thumb-suckers, even as I now shell out thousands for their braces.

As for my own approach to water, I've decided that panic will get me nowhere. Tap water is clearly still good for me, and I'll stick with my penny-pinching ways of not buying spring water at the supermarket. To be on the safe side, though, I think I'll replace that plastic bottle on my desk with a plain old drinking glass. And I just might invest in metal canteens for my kids to take to school.

• Here are 5 ways to keep estrogen-like chemicals out of your food.