H2O: Safe Drinking Water

According to a 1999 Harris poll for the National Consumers League, a majority of Americans believe that water is our second-most-threatened resource, after air. Across the country, groundwater is sullied by pesticides, fertilizers, industrial chemicals and septic systems. That's why it's crucial to protect our water at the source. "Watershed protection is much cheaper than filtration," New York City's The Riverdale Press points out in a recent editorial, warning citizens not to accept a filtration plant in an effective tradeoff that would allow more development near pristine reservoirs. In addition to supporting conservation efforts, we can evaluate the safety of our water with the new Consumer Confidence Reports that all water utilities must now provide under the Safe Drinking Water Act. The Environmental Protection Agency (EPA) requires that utilities test for 80 contaminants in water as it leaves municipal treatment plants, and list those detected. If you did not receive the first report with your water bill in Autumn 1999, call your utility for a free copy, or look for it at your local library or on EPA's website, http://www.epa.gov/safewater/dwinfo.htm.

Contaminants to Check For

Look for the EPA's maximum contaminant level (MCL), at which exposure is deemed to be safe, and the maximum contaminant level goal (MCLg), which has a margin of safety built in. Drinking water that satisfies MCLs for all contaminants is probably safe for most people, says Lynn Thorp, coordinator of the Campaign for Safe and Affordable Drinking Water. However, it still may pose a risk for vulnerable individuals, such as pregnant women and their fetuses, and people with weakened immune systems or cancer:

+ Arsenic has been linked to cancer, skin lesions, and nerve damage. The MCL of 50 micrograms per liter (µ/L), far above the World Health Organization's limit of 10 µ/L, is under review.

+ Chlorine is added to kill bacteria in most water supplies. When it reacts with organic matter in water, such as dirt, leaves and sewage, it forms a number of trihalomethanes (THMs), suspected carcinogens associated with an increased risk of miscarriage. The current MCL for total THMs is 100 µ/L, but levels higher than 75 µ/L may increase the risk of miscarriage.

+ Lead, which causes brain and nervous system damage, commonly leaches into water through old lead or lead-soldered pipes and water mains. It can also seep into water from naturally occurring deposits. Consumer Reports advises filtration of water with a lead level greater than 15 parts per billion (ppb).

+ Pathogens can include Cryptosporidium, a parasite that causes intestinal illness in healthy adults and can be fatal to those with severely weakened immune systems. The cysts of Cryptosporidium and Giardia, which causes abdominal cramps and diarrhea, are not killed by chlorine. Utilities must filter out 99.9% of Giardia, if detected. Cryptosporidium is currently unregulated. This will change by December 2001.

+ Fluoride is added to many water supplies to fight tooth decay. But high concentrations can lead to severe bone and dental problems, particularly in people with kidney disease. Levels should not exceed 4 milligrams per liter. Other toxic contaminants to look for include asbestos, cyanide, nitrogen derivatives, pesticides, solvents, dioxins and radioactive substances.

Private Water Testing?

If you have specific health concerns, draw your water from a private well, or believe that your water may be contaminated on route to your faucet, you can have it tested by a private lab. To find state-certified labs, see EPA's website, www.epa.gov/safewater, or call its Safe Drinking Water Hotline, 800/426-4791.

Two such labs that take samples by mail: National Testing Labs, www.watercheck.com, 800/458-3330; and Suburban Water Testing Lab www.h2otest.com, 800/433-6595.