MtBE In Drinking Water

Methyl tertiary-butyl ether, or MtBE as it is commonly known, is an additive used to increase the octane rating in gasoline, and also reduce air pollution by increasing the oxygen content. What started out as something good for the air has become very bad for the water. The chemical has been found in various types of water sources including shallow wells, deep bedrock wells and reservoirs. It has been detected in the water of some of the most remote well locations, and the source of contamination is not easily found.

MtBE has been detected with increasing frequency in drinking water throughout New Hampshire in the past several years. Although the US EPA has not set a formal "health-based" drinking water standard for MtBE, the New Hampshire Department of Health and Human Services Bureau of Health Risk Assessment (BHRA) has recently developed a "health-based" drinking water standard for MtBE of 13 mcg per liter for community public water systems. To appease complaints of taste and odor, the EPA has recently adopted a "non-health-based" recommendation limiting MtBE in drinking water to 20 to 40 mcg per liter.

Live animal studies suggest that drinking water with high levels of MtBE may cause stomach irrigation, liver and kidney damage, as well as affecting on the nervous system. An increased amount of liver and kidney cancer was found in rats and mice after breathing high levels of MtBE. Based upon those studies, the BHRA now considers MtBE a possible human carcinogen.

Correcting the problem is not as simple as many other volatile chemical compounds found in drinking water. Because of the variability of concentrations over time with MtBE contaminants found in the water supply, the EPA recommends several water tests to determine whether levels are rising or falling over the long term. This will provide a constant, or an average reading that can predict future levels.

Removal of MtBE from the water supply requires a system of aeration and carbon filtration. The aeration safely vents out any volatile gases, and an activated carbon filter "polishes" the water, catching anything that may not have been removed by aeration. A monitoring program that consists of periodic laboratory testing on both the incoming and outgoing water source is necessary to determine the effectiveness of the treatment. Over time the activated carbon will lose its capacity to remove MtBE, and will need to be replaced when it does.

 A comprehensive monitoring program from your water treatment specialists at Advanced Radon Mitigation will give you the peace of mind to note that your water is MtBE-free!