Filtering trichlorethylene (TCE) from water
What is TCE?
Trichlorethylene (TCE) is classified as a halogenated aliphatic organic compound. TCE is a colorless, non-flammable liquid. Due to its unique cleaning properties and solvent action, TCE has been used extensively in manufacturing, industrial cleaning solvents, paint removers, and as a “universal” degreaser for more than 50 years. TCE is also used to scrub cotton and other fabrics in the textile industry. It is used in the pharmaceutical industry as a solvent for waxes, fats, resins and oils and in the aerospace industry. Many consumer products, such as correction fluid, paint remover, adhesives, and stain removers, contained TCE. TCE was thought to be relatively harmless and was disposed of in landfills and chemical waste dumps. Improper disposal practices and leaky storage tanks also led to groundwater contamination. In California alone, an estimated 161,315 pounds of TCE were released into the environment. TCE is the most frequently detected volatile organic chemical (VOC) in groundwater in the United States. In a New Jersey study, approximately 20% of the 315 wells tested were contaminated with TCE and / or other VOCs above the 1 ppb detection limit. TCE contamination has caused water supply wells to close on Long Island, NY and Massachusetts. Detectable levels of at least one of the 18 VOCs, including TCE, were found in 15.9% of 63 water wells sampled in Nebraska.
TBI and health hazards
Cancer bioassay research conducted by the National Cancer Institute (later the National Toxicology Program) showed that exposure to trichlorethylene is carcinogenic in animals, causing liver cancer in mice and kidney cancer in rats. Recent studies in laboratory animals and observations in human populations suggest that exposure to trichlorethylene may be associated with congenital heart defects. The Eleventh Carcinogen Report of the National Toxicology Program classifies trichlorethylene as “reasonably anticipated as a human carcinogen,” based on limited evidence of carcinogenicity from human studies and sufficient evidence of carcinogenicity from experimental animal studies. Drinking or showering with TCE-contaminated water poses many health problems. TCE is rapidly absorbed into the bloodstream after inhalation and ingestion and is rapidly distributed to organs, including the liver, kidneys, and cardiovascular and nervous systems. The amount of TCE that is considered a health risk depends on many variables, such as the amount of water a person drinks, their size, their age, and whether they have other health conditions, such as an immune condition. There may be an increased risk of health effects for the most exposed and sensitive people.
TCE and drinking water contamination
TCE can quickly seep through the ground along with rainwater and into groundwater. TCE can be adsorbed onto soil particles above groundwater supplies. When groundwater seeps through TCE-contaminated soil, it collects the solvent. Municipal water supply or wastewater treatment systems that use standard practices including coagulation, sedimentation, precipitation softening, particulate filtration, and chlorination are ineffective in reducing TCE concentrations to “non-hazardous” levels. TCE contamination can be found in wells and municipal water supplies. The United States Environmental Protection Agency has set the maximum allowable level of TCE in drinking water at 5 ppb (parts per billion). Many people prefer not to be exposed to this carcinogenic chemical at any level. Fortunately, there are steps you can take to reduce your and your families’ exposure to TCE.
How do I protect myself from TCE contamination in my water supply?
A properly designed water filtration system will remove TCE. However, not all water filters remove this solvent. A filtration system using granular activated carbon (GAC) or solid block carbon cartridges is the best way to remove TCE from the water supply. The type of filter that works best for you should be based on: the amount of water you use, the available space and access to plumbing, and whether you want protection against exposure to TCE vapor.
There are two types of filter systems for TCE removal:
1. Point-of-use (POU) filters that treat the water in a sink or shower.
2. Whole-house point-of-entry (POE) filtration that treats all water entering the home, not just water from a sink or appliance. The POE filter system generally consists of a pre-filter and a granular activated carbon filtration.
For simple TCE protection at the point of entry, a counter filter is recommended. This small single cartridge filter provides protection against particulate, taste, odor and TCE. The filter installs on your tap and provides purified water for drinking and cooking. No plumbing required. To protect against TCE vapors, use a shower filter. The shower filter contains high quality activated carbon that will protect you and your family from breathing the fumes and skin exposure to TCE. A shower filter is easy to install. Just screw it onto your existing shower head.
The most complete and efficient way to protect against TCE and other organic pollutants is with a whole house activated carbon filtration system. Whole-home filtration systems provide filtered water to every tap, shower, and appliance that uses water in your home or business. All water that enters your home or business passes through activated carbon, removing TCE and other organic chemicals that cause taste, odor, and health problems.