Understanding Water Quality
Important information that everyone should know about water quality and its relation to human health.
The following sources and reports contain alarming information about water quality and potential risks related to tap water and bottled water. This source information is made available as a public service by non-profit health organizations whose only goal is to raise awareness and protect public health. We feel that these sources and reports are the most credible and factual third-party information available on this subject and highly recommend that people educate themselves on these issues.
The Breast Cancer Fund
State of the Evidence 2008: The Connection Between Breast Cancer and the Environment
On October 1, 1999, a new federal law went into effect that requires water utilities to send each customer a detailed report showing what is in their water, appropriately called “The Right To Know Amendment.” The most important thing to remember is that no matter how insistent these reports are that “contaminants in your water do not necessarily pose a health risk,” any level of contamination in our drinking water does in fact represent a danger to our health. Of the over 75,000 toxic chemicals used in our society, the EPA has only set standards (MCLs) for about 90, and those 90 Maximum Contaminant Levels are not necessarily set on “health effects.” The EPA considers limited health studies based on consumption of one certain chemical by a 175 lb. adult when setting these standards. No consideration is given to the effects on small children or the combined effects of two or more contaminants, which some studies show are magnified by as much as 1000 times. Water utilities are only required to test for the 90 contaminants that the EPA has set standards for.
Nobody knows how many toxic chemicals may actually be in tap water. According to the Ralph Nader Research Group, after reviewing thousands of pages of EPA documents acquired through the Freedom of Information Act, more than 2100 toxic chemicals have already been detected in U.S. water supplies. Virtually all public water systems have some level of contamination. The water utilities are usually quick to point out that the chemicals found in their water are “below EPA’s Maximum Levels” and in most cases they are. The fact is that even the smallest trace of a toxic chemical causes damage and science is just now starting to realize to what extent. In a recent report from the National Cancer Institute to the Surgeon General it was stated that “No level of exposure to a chemical carcinogen should be considered toxicologically insignificant to humans.”
It is recommended that you print this page and use it as a guide in interpreting your “Annual Water Quality Report.”
MCL: (Maximum Contaminant Level) This is the level at which the EPA requires corrective action and can impose penalties.
MCLG: (Maximum Contaminant Level Goal) This is the level at which the EPA has determined that unacceptable health risks may occur. Notice that the MCLG is always at or below the MCL – the law allows some unhealthy levels of contaminants. A “Superior” water system only means that it complies with EPA minimum water quality standards, not that it doesn’t contain unhealthy levels of contaminants.
ppb: (part per billion) The unit of measure used for many water-borne synthetic chemicals.
ppm: (part per million) The unit of measure used for chlorine in tap water.
mg/L: (milligram per Liter) A unit of measure used for contaminants in water.
Most Common Things To Look For: Lead, VOCs (volatile organic chemicals), Organic Contaminants, and Disinfection By-Products (THMs, Trihalomethanes), are the most noticeable problems on these reports. Often these toxic chemicals exceed the MCLGs or healthful threshold. Also these thresholds are relevant only to the one contaminant; if more than one is present the thresholds for heath risks drops considerably.