Healthy Housing and Environment Team

Web-based Information on MTBE and related topics

HEALTH Advisory About MTBE in Pascoag Drinking Water

Current MTBE levels are unacceptable.

MTBE levels in Pascoag water (as high as 600 ppb) exceed the RI Department of Health (HEALTH) maximum of 40 ppb. Even at this high level, the contamination amounts to only 1 oz of MTBE in a typical, backyard swimming pool (24ft diameter, 4ft deep) Still, customers should not drink this water or use it for cooking. This advisory provides information about MTBE’s known taste and odor problems and the possible health effects of long-term exposure to high levels of MTBE.

MTBE smells and tastes bad; strong odors often nauseate and cause stress.

The body reacts to bad tastes and odors in different ways. Bad taste and smell affect some Pascoag residents more strongly than others. Some complain that it gives them a stomachache, headache or nausea. Others don’t even notice it. Bad odors disrupt our lives and make us uncomfortable. The stress alone can make us sick—sometimes in the same ways as the bad odors.

Exposure to MTBE in Pascoag water does not exceed federal risk levels.

Exposure to MTBE in Pascoag water does not exceed federal risk levels. Federal guidance on MTBE exposures using studies about known harmful effects on laboratory animals and human subjects is not consistent. One federal agency, the Agency for Toxic Substances and Disease Registry, provides guidelines for safe exposures up to one year-including exposures for individuals who are known to be sensitive to chemicals. The levels of MTBE in Pascoag drinking water do not exceed these federal guidance levels--studies do not indicate that there are health effects at these levels. However, the state and EPA use a stricter limit, taking the effects on the most sensitive individuals into account. Our advisory will remain in effect until MTBE levels are below 40 ppb.

Using water contaminated by MTBE causes three types of exposure.

First, we ingest MTBE when we drink the water or use the water for making ice, making beverages or washing food. MTBE can travel from the water into the air we breathe. We inhale MTBE when we are in areas where water is being used, especially large quantities of hot water. Some MTBE can also be absorbed through the skin when bathing or showering.

Cars, lawnmowers, and other gasoline powered equipment put MTBE (and other fumes) into the air that we breathe. Although of concern, these everyday exposures are generally less than those resulting from using MTBE contaminated water.

Prevent further MTBE increases by conserving water.

MTBE pollution rests in the ground. The more we use the water, the more MTBE moves towards Pascoag drinking water wells. Conserving water slows the movement of MTBE towards the wells and helps prevent rising MTBE levels. Reducing the amount of water you use at home also reduces how much MTBE gets into the air you breathe.

HEALTH Advisories

HEALTH’s advisories, listed below, help you in two ways: they limit your exposure to MTBE and they help prevent drawing more MTBE contamination into the wells by promoting water conservation.

Protect your water supply from contamination. Learn about potential sources of contamination and help your community keep the drinking water safe and clean.