点击显示 收起
Nov. 7, 2008 -- Americans drank 9 billion gallons of bottled water last year, or slightly more than 29 gallons for every man, woman, and child in the country.
They also spent $22 billion on a product that critics of the bottled water industry say they should be getting for free from their home faucets.
Most of the criticism has focused on the environmental impact of bottled water. But an investigation released two weeks ago also raises questions about the purity and even safety of commercially available water.
WebMD looked into many commonly asked questions and concerns about bottled water. Here is what we found:
The Environmental Working Group tested 10 best-selling brands of bottled water for 170 contaminants and found different mixtures of 38 contaminants, including bacteria, fertilizer, and industrial chemicals at levels similar to those allowed in tap water.
Two of the samples, bought in San Francisco, contained the chemical compound trihalometrane in levels that exceeded the amount allowed in California.
"The bottled water industry really presents this image of purity, but our investigation demonstrated that it is really hit or miss," Environmental Working Group senior scientist Olga Naidenko, PhD, tells WebMD.
But the International Bottled Water Association, which represents most bottlers, charged that the group's report contained "false claims and exaggerations" and noted that the group's sample was not representative of the hundreds of bottled waters on the market.
Joseph Doss, president of the International Bottled Water Association, tells WebMD that California has much stricter contamination restrictions than the FDA. He says the state's allowed level of trihalometrane is eight times lower than the level allowed by the federal government.
Roughly 45% of the water sold in single-serve bottles comes from a municipal water source.
By law, bottled water that comes from a municipal water supply has to disclose this on its label unless the bottler takes steps to further purify the water, which most do. In this case, the label will say "purified water" or "purified drinking water," but the original source is probably tap water.
Water labeled "spring water" comes from an underground water spring, but it may be piped to the bottling plant.
"Mineral water" comes from an underground source and must contain no less than 250 parts per million total dissolved solids, such as salts, sulfur compounds, and gasses. No minerals may be added to the water by the bottler.
"Artesian water" or "artesian well water" must come from a well that taps a confined aquifer.
You probably can't. Tap water is regulated by the Environmental Protection Agency (EPA), which requires yearly public reports identifying the contaminants found in local water sources. But bottled water is regulated by the FDA, which has no such requirement.