Which is safer, bottled or tap water?
Assuming that both the municipal tap water source and the bottler are in compliance with regulations, the experts contacted by WebMD say bottled water is no safer than tap water and tap is no safer than bottled.
The experts point to two cases where bottled water may be recommended -- in emergency situations when contaminants in the local water supply exceed permitted standards and in homes where corroded plumbing could cause lead or copper to contaminate drinking water.
In the first instance, water suppliers are required to notify the community and they may even provide bottled water until the problem has been solved. Homeowners worried about their pipes can have their drinking water tested. Halden says most people choose bottled water for convenience, not safety.
"We have invested in the infrastructure to provide pure, safe, drinking water to the population," he says. "In large cities, water quality is tested hourly, not just once a day."
While that may be true, a recent report by the Associated Press raised new concerns about the purity of tap water.
Its five-month investigation found evidence of a wide range of prescription and over-the-counter drugs -- including antidepressants, antibiotics, anticonvulsants, and sex hormones -- in tested samples of municipal water taken from taps throughout the country.
Twenty-four of the 28 water samples taken from major metropolitan area water supplies contained evidence of drug contamination.
The concentrations of these pharmaceuticals were very small. But the report noted that the EPA has not set safety limits for drugs in water and does not require testing for them.
If I drink tap water, should I use a filter?
If you live in a home with older pipes, have odor or taste issues with your tap water, or just want an extra level of protection, a filter may be a good idea. But you have to get the right one for your specific problem, Janssen says.
"It is important to know what you are trying to filter out before you spend the money," she says. "A reverse osmosis filter will get rid of most contaminants, but charcoal may be enough for odor and taste problems."