According to a 1999 study by the Natural Resources Defense Council (NRDC), on average, bottled water costs between 240 and 10,000 times more than tap water in the United States. In 1990, a gallon of bottled water, on average, cost 90 cents, whereas 500 gallons of tap water cost only 80 cents.
The study was conducted in light of the growing demand for bottled water in the United States. About one-third of Americans are believed to drink bottled water on a regular basis. The NRDC has discovered that not only does bottled water cost much more than tap water, it is not necessarily better or safer than tap water. In fact, some "bottled water" is in fact just bottled tap water. Nearly one-third of the 103 brands of bottled water tested by the NRDC were found to be contaminated with bacteria or chemicals. The regulations applied to tap water appear to be stricter than the regulations applied to bottled water in many states in the United States.
Moreover, bottled water is not always superior to tap water in essential minerals like calcium and magnesium. Environmentalists are also proponents of tap water since all plastic bottles used for bottled water are not recycled.
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