National Drinking Water Database
1,1,1-Trichloroethane in Maryland
1,1,1-Trichloroethane is an industrial cleaning solvent that contaminates drinking water sources due to releases from metal degreasing sites and chemicals factories. [read more]
1,1,1-Trichloroethane is used industrially as a solvent for adhesives (including food packaging adhesives), metal degreasers, pesticides, aerosols, inks and stain repellents. 1,1,1-Trichloroethane is also used as an intermediate in the manufacture of other chlorinated organic compounds, and as a solvent for cleaning electrical equipment, photographic film and various instruments (U.S. Environmental Protection Agency (USEPA) 2009b). Annually, more than 500 million pounds of 1,1,1-trichloroethane are produced in the U.S. (USEPA 2008d).
Exposures to 1,1,1-trichloroethane are common in the home. One recent study found that 216 out of 1159 household products tested in a market basket survey had detectable levels of 1,1,1-trichloroethane. These products included oven cleaners (makes up 97 percent of the solution), drain cleaners (98 percent), electric shaver cleaners (2.5-20.3 percent), wood cleaners (12.3-20.4 percent), and aerosol cleaners (0.2-84 percent) (Hazardous Substances Data Bank (HSDB) 2003a).
From its many uses in household products and from its industrial uses, 1,1,1-trichloroethane has become a contaminant in drinking water sources. Environmental releases and water contamination with 1,1,1-trichloroethane are primarily associated with the chemical industry and metal degreasing sites, which discharge hundreds of thousands of pounds of 1,1,1-trichloroethane every year (USEPA 2009i).
Drinking water contaminant fact sheets written by EPA note that exposure to 1,1,1-trichloroethane in drinking water above the maximum contaminant level (MCL) of 0.2 parts per million (ppm) can cause damage to the liver, central nervous system and circulatory system (USEPA 2009b). In laboratory studies, chemicals similar to 1,1,1-trichloroethane, called chlorinated ethanes, are known to damage DNA and cause cancer in experimental animals (Agency for Toxic Substances and Disease Registry (ATSDR) 1995a). Other effects noted in high dose laboratory animal studies include damage to the testes and birth defects. Occupational exposure to 1,1,1-trichloroethane has been linked with impaired memory, balance difficulties, decreased blood pressure and heart damage (ATSDR 1995a).
The Most Polluted Communities in Maryland
1 water utilities reported detecting 1,1,1-Trichloroethane in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies
Ranked by highest average 1,1,1-Trichloroethane level
|Rank||System||Population Served||Positive test results of total reported tests||Average Level|
|1||Town of Manchester|
|4,000||1 of 10||0.16 ppb|
(0 to 1.6 ppb)
Health Based Limits for 1,1,1-Trichloroethane
|Maximum Contaminant Limit (MCL)||The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency.||200 ppb|
|Maximum Contaminant Limit Goal (MCLG)||A non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.||200 ppb|
|Lifetime health-based limit, non-cancer risk||Concentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for a lifetime of exposure. The Lifetime health-based limit (or Health Advisory, HA) is based on exposure for a a 70-kg adult consuming 2 liters of water per day. Source: U.S. Environmental Protection Agency.||200 ppb|
|California Public Health Goals||Defined by the State of California Office of Environmental Health Hazard Assessment (OEHHA) as the level of contaminant that is allowed in drinking water. For acutely toxic substances, levels are set at which scientific evidence indicates that no known or anticipated adverse effects on health will occur, plus an adequate margin-of safety. PHGs for carcinogens or other substances which can cause chronic disease shall be based solely on health effects without regard to cost impacts and shall be set at levels which OEHHA has determined do not pose any significant risk to health.||1000 ppb|
|Drinking Water Equivalent Level||A lifetime exposure concentration protective of adverse, noncarcinogenic health effects, that assumes all of the exposure to a contaminant is from drinking water. Source: U.S. Environmental Protection Agency.||1000 ppb|
|Children's health-based limit for 10-day exposure||Concentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic effects for up to ten days of exposure. The Ten-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.||40000 ppb|
|Children's health-based limit for 1-day exposure||Concentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for up to one day of exposure. The One-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.||100000 ppb|
Violation Summary for 1,1,1-Trichloroethane in Maryland
Data from the U.S. Environmental Protection Agency includes the following violations of federal standards in Maryland since 2004
|Violation Type||Number of Violations|
|Failure to monitor regularly||1|