The bottled water industry promotes an image of purity, but comprehensive testing by the Environmental Working Group (EWG) reveals a surprising array of chemical contaminants in every bottled water brand analyzed, including toxic byproducts of chlorination in Walmart’s Sam’s Choice and Giant Supermarket's Acadia brands, at levels no different than routinely found in tap water. Several Sam's Choice samples purchased in California exceeded legal limits for bottled water contaminants in that state. Cancer-causing contaminants in bottled water purchased in 5 states (North Carolina, California, Virginia, Delaware and Maryland) and the District of Columbia substantially exceeded the voluntary standards established by the bottled water industry.
Unlike tap water, where consumers are provided with test results every year, the bottled water industry does not disclose the results of any contaminant testing that it conducts. Instead, the industry hides behind the claim that bottled water is held to the same safety standards as tap water. But with promotional campaigns saturated with images of mountain springs, and prices 1,900 times the price of tap water, consumers are clearly led to believe that they are buying a product that has been purified to a level beyond the water that comes out of the garden hose.
http://www.ewg.org/reports/bottledwater
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