Our Mission: We are igniting a movement that inspires parents to protect young children from harmful chemicals. Donate »
Charity Navigator 4 Star CharityBlog
Safe Drinking Water: What’s a Consumer Confidence Report?
Sarah Milstein
The Green Guide #79Saturday, June 23, 2007
The United States has one of the safest water supplies in the world, but across the country, groundwater is increasingly 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 as 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 Consumer Confidence Reports that all water utilities must provide under the Safe Drinking Water Act.
The U.S. Environmental Protection Agency (EPA) requires that utilities test for 90 contaminants in water as it leaves municipal treatment plants and list those detected. If have not received a report, call your utility for a free copy, or look for it at your local library or at EPA’s Safe Drinking Water site.
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.
The following are some of contaminants that may be detected.
Arsenic has been linked to cancer, skin lesions, and nerve damage. The current MCL is 10 parts per billion (ppb). Editors Note: A 2001 study by Dartmouth Medical School researchers, published in Environmental Health Perspectives has also linked arsenic to endocrine disruption.
Atrazine is the second most commonly used herbicide in the U.S., used primarily in the Midwest and Delaware on corn. Low levels of atrazine have been linked to low birth weight, premature birth, low sperm quality and developmental defects in newborns. The MCL for atrazine is 3 parts per billion.
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****** (link to safe pipes mean safe water doc)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. Editor's Note: As of January 1, 2002, public utilities must remove 99% of cryptosporidium, if detected.
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. For a full list of regulated contaminants and their MCLs, see EPA's Current Drinking Water Standards.
See also
Posted by clinicas dentales on 08/24 at 11:56 PM
The new guidelines call for water agencies to identify the likely source of contaminants in the water, and include a special advisory for people who may be at special risk, such as those with weakened immune systems. clinicas dentales