Tap water in all U.S. cities is better tested and regulated for purity than bottled water, according to the Natural Resources Defense Council (NRDC). But your tap water’s quality still depends on how well your watershed and aquifers are protected, how effectively water is treated to remove pollutants, and the condition of the pipes that bring it to your home. In a 2003 report on drinking water in 19 large U.S. cities, the NRDC concluded that only Chicago rated “excellent” for water quality; five cities rated “good,” eight were “fair” and five, “poor.”
Depending on where you live, tap water contaminants can run the gamut from bacteria to pesticides, nitrate (from fertilizers or animal waste) and even arsenic or lead. Municipal tap water is tested regularly, and its contents are published in reports enclosed with water bills. To get a copy of your report, call your local water utility or click on EPA.gov/safewater/dwinfo.htm. For help interpreting the report, go to Safe-drinking-water.org/rtk.html.
If your home has lead pipes or a private well, you might want to test your own water. Check with the EPA Safe Drinking Water Hotline, (800) 426-4791, or see www.EPA.gov/safewater/privatewells/labs.html for a list of certified water-testing labs in your state. Visit www.NSF.org to search for the water-treatment systems that are best to remove the contaminants in your water.
Keep in mind that drinking isn’t the only way you’re exposed to water contaminants. Chlorine or traces of heavy metals can be inhaled or absorbed through skin during a bath or shower. You can remove many of these with special shower filters.
Get the lead out
The Environmental Protection Agency (EPA) estimates that about 20 percent of human lead exposure comes from drinking water. Concerns have ratcheted up since late 2004, when the Washington Post reported that many cities have withheld test results showing lead levels in excess of safety standards. Lead leaches into water that stands in pipes overnight, so let your tap run 30 to 60 seconds first thing in the morning to flush that water away. Hot water leaches more lead than cold, so don’t use hot tap water for drinking or cooking. A carbon filter carafe, such as those made by Brita or PUR, will remove lead and other contaminants.
All bottled up
Because of the concerns over tap water, many people have opted instead for bottled water. Despite the paeans to purity in bottled-water advertisements, however, bottled water can’t be presumed innocent. When the NRDC tested more than 1,000 bottles of 103 brands of water in 1999, about one-third contained contaminants—including synthetic chemicals, bacteria and arsenic—that exceeded allowable limits under either state or bottled water–industry standards.
The government requires products labeled “spring water” to come from an identifiable source, but that source doesn’t have to be a pristine wilderness. NRDC tested one brand of “spring water” labeled with a picture of a mountain lake: It actually flowed from an industrial parking lot next to a hazardous waste site.
Up to 40 percent of bottled water comes from municipal taps, and testing requirements for bacteria and chemical contaminents are less frequent and less rigorous that those for city tap water. On the other hand, manufacturers can only label water “purified” or “distilled” if it has been treated, and it’s usually cheaper—a good option to buy or store for emergencies.
That "plastic" taste
Some unsavory chemicals from plastic water bottles can leach into the contents, particularly if the plastic is scratched, heated or degraded. These include bisphenol-A, a component of #7 polycarbonate (the plastic found in many baby bottles and reusable sports bottles), and plasticizers known as phthalates, which may disrupt hormones and have been found to leach from bottles made of #1 PET (polyethylene terepthalate—the plastic used for most disposable water bottles) after nine months of storage. In 2000, the Consumers Union found bisphenol-A in water from 8 out of 10 five-gallon polycarbonate water jugs.
While it’s healthier for the environment to reuse plastic water bottles, check them for signs of wear and wash them well to prevent bacterial buildup. Don’t leave water in them for too long or let them heat up. Some harder plastic bottles are better than others. Lightweight stainless-steel bottles are better still.
Whether we drink bottled water for health reasons or not, plastic containers weigh heavily on the earth. It takes more than 1.5 million barrels of oil a year to make enough PET plastic water bottles for the American market, according to the Earth Policy Institute. Even though PET plastic is recyclable in many locations, about 90 percent of used bottles—30 million a day—end up in landfills.
How to Choose a Water Filter
Installing a home water filter will remove the pollutants found in your tap water. Select one that’s certified by the National Sanitation Foundation. Here’s an overview of commonly used filters:
Carbon: Carbon, a porous material, absorbs impurities as the water passes through. Carbon may be included in carafe or pitcher filters, faucet-mounted models, undersink models, and whole-house or point-of-entry systems.
Ceramic: Often combined with carbon filters, these help remove bacteria,asbestos and sediments.
Reverse Osmosis: These systems push water through a semipermeable membrane, which acts as an extremely fine filter. However, they waste four to nine gallons of water for every gallon filtered.
Ultraviolet Light: Disinfects water, killing bacteria.
Distillers: Probably the least practical home method, distillers boil and condense water. Tabletop units are available, but they use lots of electricity, generate excess heat and require regular cleaning. In a pinch, buy distilled water.
What's In Your Tap Water?
These contaminants are common in U.S. water supplies:
• Arsenic, a poison that also can cause cancer, is found in all 50 states but is highest in the Southwest.
• Atrazine, a widely used pesticide, may cause hormone disruption, cancer, muscular degeneration and cardiovascular damage. Found in all 50 states, it’s most common in the Mississippi River Basin during spring runoff.
• Lead, a heavy metal, can cause brain damage and developmental problems in children and it adversely affects blood pressure, kidneys and red blood cells. Lead has been found to exceed the national standard in many U.S. cities, such as Boston and Seattle, and is of high concern in many others, such as Los Angeles and Washington, D.C.
• Methyl Tertiary-Butyl Ether (MTBE), a gasoline additive, can leak into groundwater from underground fuel storage, spills and storm-water runoff and may cause cancer.
• Pathogens such as Cryptosporidium, E. coli and giardia are carried by animal and human waste; they cause gastrointestinal illness that can be life-threatening for individuals with weakened immune systems.
• Perchlorate is a contaminant from rocket fuel that harms the thyroid and may cause cancer. Leakage from a Nevada plant has reportedly contaminated the Colorado River, impacting drinking water in Los Angeles, San Diego, Phoenix and elsewhere. Currently, there’s no EPA standard for perchlorate, but its risks are being assessed.
• Trihalomethanes (THMs), including chloroform, are byproducts of chlorine treatment and are linked to cancer, miscarriages and birth defects. THMs can occur seasonally, for instance after heavy rains, when chlorine reacts with organic matter such as leaves and animal waste that wash into watersheds.
Mindy Pennybacker is editor of The Green Guide , a print and online publication that helps people protect the environment and their families’ health through informed product choices and other actions.