I've fielded lots of questions on this topic lately. My favorite came from a 9-year-old girl participating in one of our studies on environmental contaminants, who asked: "What's the problem, anyway? I'm not eating the bottle, just drinking the water." Putting the smarty-pants factor aside, it's a good point. But chemicals from the plastic end up in the water — and scientists are trying to figure out whether this should worry us. In a report released last April, the federal government's National Toxicology Program expressed "some concern" that one chemical in many plastics could harm children's neurological development and reproductive organs.
More: Hydration BasicsThe possible bad guy is a chemical called bisphenol A, or BPA. Increasingly strong evidence suggests that BPA is an endocrine disruptor, which means it can mimic or block the function of hormones. In animal research, BPA and other endocrine disruptors have been linked to a range of unwanted effects — earlier puberty in females, enlarged prostates in males, and even cancer. (One recent review suggested that in some circumstances, endocrine disruptors could increase the risk of obesity!)
BPA is in many sports bottles, watercooler jugs, and baby bottles. These are usually marked by a "7" inside the recycling symbol (though not all "7" products contain BPA). Heating these bottles can be particularly problematic: When scientists poured boiling water into a number 7 plastic bottle, BPA entered into the water 55 times faster than when they used water at room temperature. So don't put your sports bottle (or a baby bottle!) into the dishwasher or microwave.
This isn't a panic situation. But you get BPA and phthalates from many sources in the environment — so why increase your consumption if you can avoid it? Get cheaper, greener, and healthier water by taking these easy steps:
PUR are popular brands, and both companies say that their plastic pitchers contain no BPA.
On the go: Put your tap water into an aluminum or stainless steel sports bottle, such as those by Klean Kanteen or SIGG — or a new, BPA-free plastic sports bottle from Nalgene.
In a store: For those parched times when you don't have your own bottle handy, pick bottled water instead of a sugary drink. Just be sure to recycle!race near you.