A debate over water is boiling over in the United States and elsewhere amid growing environmental concerns about bottled water and questions about safety of tap water.

The US Conference of Mayors in June passed a resolution calling for a phasing out of bottled water by municipalities and promotion of the importance of public water supplies. While largely symbolic, the vote highlighted a growing movement opposing regular use of bottled water because of its plastic waste and energy costs to transport drinking supplies.

Janet Larsen, director of research at the Earth Policy Institute, cites a "backlash against bottled water as more people are realizing what they get out of the bottles is not any better than what they get out of the faucet." The Pacific Institute, a California think thank on sustainability issues, contends that producing bottles for US water consumption required the equivalent of more than 17 million barrels of oil in 2006, not including the energy for transportation. The group says bottling water for Americans produces more than 2.5 million tons of carbon dioxide and consumes three liters of water for each liter of bottled water produced.

The debate in the US mirrors that taking place worldwide in places such as Paris; Liverpool, England; Florence, Italy; Vancouver, Canada. According to the EPI, the issue making waves among policymakers in locations including Denmark and New South Wales, Australia, among others. The backlash comes even amid surging sales of bottled water in the United States. Some of this is linked to concerns about contamination of public water supplies, although critics of the industry say marketing hype is a greater factor.

Aficionados of Evian from France or Fiji from the South Pacific swear by the taste and health benefits of those waters, but others decry the high cost of energy for a product that may not be any better than local water. A Natural Resources Defense Council concluded that "most of the tested waters were found to be of high quality (but) some brands were contaminated."

The group said bottled waters "are subject to less rigorous testing and purity standards than those which apply to city tap water." In fact, says the group "about one-fourth of bottled water is actually bottled tap water" while government rules "allow bottlers to call their product 'spring water' even though it may be brought to the surface using a pumped well, and it may be treated with chemicals."

Americans drank about 8.8 billion gallons (33 billion liters) of packaged water in 2007, or 15 percent of their total liquid intake, according to the Beverage Marketing Corp. Per capita bottled US water consumption is up to 29 gallons (109 liters) per year, from 20 gallons in 2002.