A Clear Look at Water Bottles

A Prevention reader asks, "Should I stop using plastic water bottles?" The short answer is no. You don't need to round up your plastic water bottles and banish them to the recycling bin. But reducing their use — drastically, if possible — is a smart idea for your wallet, the environment, and your health.

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.

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The 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.

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On the other hand, you may be relieved to hear that most of the single-serving water bottles sold at grocery stores don't contain BPA. They're made of polyethylene terephthalate (PETE or PET), designated by a number "1" in the recycling sign. But even though PETE doesn't contain BPA, it does contain other chemicals called phthalates — which are also believed to be endocrine disruptors. Like BPA, these chemicals leach into the water more quickly when the plastic is heated, so don't leave these water bottles in a hot car or out in the sun.

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:

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At home: Save yourself some money — and save the environment some grief — by drinking from the sink. Municipal tap water is constantly tested to ensure its safety. If you don't like the chlorine taste or are concerned about other impurities such as lead, use an activated carbon-based filter. Brita and 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!

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