April 18, 2008
Bottled water companies say their high-tech treatment systems produce consistently clean, good-tasting water that’s free of any impurities—including unregulated pharmaceuticals and industrial chemicals that have been found in tap water.
A Tribune/RedEye investigation found that samples of the three top-selling bottled water brands in Chicago did not contain any of the 15 pharmaceuticals tested for, or the Teflon and Scotchgard chemicals found in Chicago’s drinking water.
Though bottled water is not directly subject to the Safe Drinking Water Act that regulates public drinking water, it is regulated by the Food and Drug Administration, which has similar standards that limit regulated contaminants. Unlike drinking water utilities, however, bottled water companies do not have to report their results to the public.
Bottled water companies, like tap water providers, aren’t required by the government to test for pharmaceuticals. Two bottled water companies said they test for pharmaceuticals but would not provide details about their testing.
The three bottled water brands tested by RedEye and the Tribune were Nestle’s Ice Mountain, drawn from a spring in Mecosta, MI.; and Pepsi’s Aquafina and Coca-Cola’s Dasani, which are both purified Lake Michigan tap water. Ice Mountain water is passed through microfilters to remove particles and through ultraviolet light to kill bacteria, Nestle says.
The company does test Ice Mountain for pharmaceuticals, said Kevin Mathews, director of health and environmental affairs for Nestle Waters North America. He declined to provide results. Representatives for Aquafina and Dasani say their multi-step purification systems eliminate all contaminants in their bottled water, including pharmaceuticals. Aquafina, which in the Chicago area comes from Munster, IN., tap water, is treated in a seven-step purification system that includes filtration, reverse osmosis to remove dissolved solids, charcoal filtration to remove the chlorine taste and ozonization to repel unwanted particles, the company says.
Dasani, which in the Chicago market is tap water pulled from suburban Alsip and Niles, undergoes a similar process. Minerals are added for taste, the company says. Pepsi spokeswoman Nicole Bradley said Aquafina tests for pharmaceuticals, but she declined to provide any details or test results, saying the “manufacturing, quality assurance and analytical processes are proprietary.”
Dasani does not test its water for pharmaceuticals, Coca-Cola spokesman Ray Crockett said.
Water treatment experts say reverse osmosis, a process that strains water through a semi-permeable membrane to catch contaminants, is the most sophisticated treatment method available, and should remove nearly all impurities from water. Most municipal drinking water utilities contend the technology is too expensive for taxpayers.
While most pharmaceuticals have a molecular weight large enough to prevent them from getting through the membrane pores, that isn’t always the case, said Joseph Harrison, technical director of the Water Quality Association, a Lisle based trade association representing the water treatment industry.
“If it breaks down into a small enough metabolite, those kinds of things can [get] through,” Harrison said.
Still, reverse osmosis “is one of the best thing we have for high-purity water treatment,” he said.
How we did it Using collection methods and containers provided by the University of Iowa Hygienic Laboratory, Tribune and RedEye reporters obtained samples of drinking water on March 17 from fountains at City Hall, Sherman Elementary on the South Side and the Waukegan Public Library. Water from a tap at Tribune Tower was poured through a Brita filter before collection.
Sealed bottles of the top three bottled waters in the Chicago market—Ice Mountain, Dasani and Aquafina—also were tested.
Following the laboratory’s instructions, the reporters did not use caffeine or tobacco for more than 24 hours before collecting the samples. They wore nitrile gloves and ran each fountain or tap for 2 minutes before collecting the samples. Each jar was marked with the location and time of collection, packed in ice and shipped overnight to the Iowa lab in sealed coolers.
The water was tested for 44 contaminants, including regulated pesticides and metals and unregulated pharmaceuticals and industrial chemicals.
One test result for bottled water was discarded by the Tribune. The newspaper had asked the lab for a retest of the sample, but the bottle had been thrown away. New tests were performed on different bottles of that brand.
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