Water Facts

Maximum Contaminant Level Goals vs. Maximum Contaminant Levels

The environment has changed a lot in the last fifty years. Manufacturing and agricultural activities, along with our growing population, add an enormous amount of potentially hazardous materials to our environment.

As a result, the U.S. Environmental Agency (EPA) and others have detected more than 700 different organic compounds in treated drinking-water supplies.

Water coming from public systems is tested regularly and must meet standards set by the EPA. Currently, they regulate only 60 substances.

The first standard—the Maximum Contaminant Level Goal (MCLG)—is not enforceable. MCLGs are set at zero for contaminants that are known to be probable human carcinogens. For noncarcinogens, MCLGs are set at a level that includes a margin of safety so as to prevent adverse health effects.

The second standard—the Maximum Contaminant Level (MCL)— is enforceable. MCLs are set as close to the MCLGs as possible, taking into account the technological and economic limitations of the public water supplier.

 

Contaminants	Potential Health Effects	MCLG (mg/L)	MCL (mg/L)
Benzene	Anemia Increased risk of cancer	0	0.005
Carbon Tetrachloride	Liver problems Immune deficiencies	0	0.005
Polychlorinated Biphenyls, Aroclor	Liver problems Immune deficiencies	0	0.0005
Tetrachloroethylene	Increased risk of cancer	0	0.005
Lead	Kidney problems High blood pressure Delays in physical or mental development in children	0	0.015

RainSoft recommends that you ask your public utility for a contaminant level report. By law, they must provide it to you.

The contaminants listed above are not necessarily present in your water.