How can I tell whether the water in my house is safe to drink?
It's not easy. You can rely on your senses to alert you to a few of the more unappetizing things that spill into your drinking glass — like sulfur, with its distinctive rotten-egg smell, or too much chlorine.
The Water Quality Association offers an interactive Diagnose Your Drinking Water tool on its Web site, which can help you figure out why your tap water smells like rotten eggs, tastes like salt, or spots your glasses. Advice is also available on how to treat a problem once you've identified it. But some of the most serious — and most common — contaminants, such as bacteria, viruses, lead, and other chemicals, can't be tasted or smelled.
The water from most municipal systems in the United States is safe, because any system that serves 25 people or more is required to comply with the federal Safe Drinking Water Act. Your water comes from a municipal system unless you have a private well on your property or live in a rural area where a number of families share a well. The water system must test regularly for potentially harmful contaminants and alert the public if any are above acceptable limits.
Unless you've heard otherwise, you can be reasonably confident that your water meets federal standards. Still, there's only one way to know for sure what's in your water, and that's to have it tested.
How can I test my tap water?
If you're on a public or municipal water line in the United States, call your local water supplier (the number's on your water bill). By law, the supplier must test its processed water regularly and provide you with a copy of the results, called a Consumer Confidence Report, annually as well as on demand.
Many water agencies across the country now make their annual water quality reports available online. You can access these reports on the Environmental Protection Agency's Web site.
If you contact your local agency by phone, ask for a test of the water from your own faucets to find out whether any contaminants are getting into the water between the treatment plant and your drinking glass. Some suppliers will do this test free of charge.
If your water supplier won't test your water, you'll need to have the test done by a state-certified lab. To find one in your area, call the Environmental Protection Agency's Safe Drinking Water hotline at (800) 426-4791, go to the EPA's Web site for a list of state certification offices, or look in the Yellow Pages under "Laboratories — Testing."
Alternatively, you can use a nationwide testing service: Underwriters Laboratories will test your water for a variety of contaminants, from fecal bacteria to industrial pollutants, and get the results to you in about a week. The price depends on how many contaminants you want to test for: It can range from $30 for a simple mercury screen, to $500 for a 94-contaminant screen.
You can also test your water yourself, using a home test kit. These kits can't test for everything, but they detect lead, arsenic, pesticides, and bacteria. Two reputable ones are PurTest and Discover testing. The kits sell for $10 to $30.
In any case, be sure to test what's called first-draw water — the stuff that comes out of your faucet when you first turn on the tap in the morning. If contaminants are leaching from the plumbing pipes into your water, the level of contamination will be highest after the water has sat in the pipes overnight.
Although the EPA says that more than 90 percent of water systems in this country meet its water quality standards, several contaminants can make their way into the water supply. These include arsenic, viruses and other disease-causing organisms, chlorine by-products, industrial and agricultural pollutants, and lead.
In concentrations of more than 15 parts per billion (ppb), lead can be very dangerous to infants and children, leading to delays in physical and mental development, neurological disorders, kidney disease, and learning disabilities. (Contaminants are measured by how many particles of the substance are present in a billion particles of water — 15 ppb means 15 particles of lead in a billion particles of water.)
Have your water tested for lead if you have lead pipes or brass faucets (which may contain lead), and for copper if you have copper pipes. Lead solder could legally be used to join plumbing pipes until 1986, but lead is a concern even if you live in a brand-new home. Faucets and pipes are still allowed to contain as much as 8 percent lead and have been shown to leach the metal in significant amounts, particularly when they're new.( source-baby center)