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Tetrachloroethylene

CASRN 127-18-4

Physical Properties

Tetrachloroethylene is a nonflammable, colorless liquid at room temperature with a sharp, sweet odor. It evaporates very easily into the air. Most people can begin to smell trichloroethylene in air when there is around 1 part of trichloroethylene per million parts of air (ppm).

Uses

Tetrachloroethylene is a synthetic chemical that is widely used for dry cleaning fabrics and for metal degreasing operations. It is also used as a starting material (building block) for making other chemicals and is used in some consumer products. Other names for tetrachloroethylene include perchloroethylene, PCE, perc, tetrachloroethene, perclene, and perchlor.

Source of Exposure in Iowa

Most of the tetrachloroethylene used is released into the atmosphere by evaporation primarily from use in degreasing operations and from evaporative losses in the dry cleaning industry. Workers who use tetrachloroethylene in the degreasing and dry cleaning industries are exposed to the highest amounts of tetrachloroethylene. Tetrachloroethylene can find its way into groundwater and then into public or private drinking water wells from spills, improper disposal, and from leaky storage containers or piping.

Health Effects from Acute or Large Exposures

When concentrations of tetrachloroethylene in air are high - particularly in closed, poorly ventilated areas - single exposures can cause dizziness, headache, sleepiness, confusion, nausea, difficulty in speaking and walking, unconsciousness, and death. Irritation or skin rashes may result from repeated or extended skin contact with tetrachloroethylene.

Health Effects from Smaller, Chronic Exposures

Breathing small amounts of tetrachloroethylene may cause headaches, lung irritation, dizziness, poor coordination, and difficulty concentrating. Tetrachloroethylene is reasonably anticipated to be a human carcinogen based upon incidences of liver cancer and leukemia incidences in animal studies.

Toluene

CASRN 108-88-3

Physical Properties

Toluene is a colorless liquid with a sweet, pungent, benzene-like odor. Its vapor is heavier than air and may accumulate in low-lying areas. Toluene is volatile and readily produces flammable and toxic concentrations at room temperature.

Uses

Toluene is a common solvent and is used in making paints and paint thinners, fingernail polish, lacquers, adhesives, rubber and in some printing and leather tanning processes. It is used extensively in the rubber, chemical, paint, dye, glue, printing, and pharmaceutical industries.

Source of Exposure in Iowa

Toluene is among the most abundantly produced chemicals in the United States. It occurs naturally in crude oil and is produced in the process of making gasoline and other fuels and as a by-product in the manufacture of styrene. People are exposed to toluene from many sources, including drinking water, food, air, and consumer products. Toluene enters the environment when materials such as paints, paint thinners, adhesives, fingernail polish, and gasoline evaporate and become mixed with the air. It can get into surface water and ground water from spills and leaking underground storage tanks. Leaking underground storage tanks also contaminate the soil with toluene and other petroleum product components. Automobile exhaust also puts toluene into the air. People who work with gasoline, kerosene, heating oil, paints, and lacquers are at the greatest risk of exposure. Printers are also exposed to toluene in the workplace. Smokers are exposed to small amounts of toluene in cigarette smoke.

Health Effects from Acute or Large Exposures

Toluene can easily cause toxic health effects when inhaled or ingested. Skin absorption occurs more slowly. Breathing in vapors is the most common route of exposure. Toluene can irritate the skin, eyes, and respiratory tract. Symptoms of toluene poisoning include central nervous system (CNS) effects (headache, dizziness, lack of muscle coordination, drowsiness, euphoria, hallucinations, tremors, seizures, and coma), ventricular arrhythmias, chemical pneumonitis, respiratory depression, nausea, vomiting, and electrolyte imbalances. At high levels, toluene can possibly damage kidneys. Low to moderate levels can cause tiredness, confusion, weakness, drunken-type actions, memory loss, nausea, loss of appetite, and hearing and color vision loss.

Health Effects from Smaller, Chronic Exposures

The United States Environmental Protection Agency (EPA) has determined that toluene can not be classified as a carcinogen. Studies in humans and animals generally indicate that toluene alone does not cause cancer. However in industry, other chemicals such as benzene and ethylbenzene are frequently mixed with toluene to make a product. Exposure to toluene mixtures containing these other chemicals can cause cancer since benzene is known to cause cancer in humans, and ethylbenzene has been determined to be a possible human carcinogen. Pregnant and nursing mothers should avoid exposure to toluene, as it crosses the placenta and is excreted in breast milk.

Trichloroethylene

CASRN 79-01-6

Physical Properties

Trichloroethylene is a nonflammable, colorless liquid at room temperature with a somewhat sweet odor and a sweet, burning taste. Most people can begin to smell trichloroethylene in air when there are around 100 parts of trichloroethylene per million parts of air (ppm).

Uses

Trichloroethylene is used as a general solvent or as a component of solvent blends and used with adhesives, lubricants, paints, varnishes, paint strippers, pesticides, and cold metal cleaners. Trichloroethylene is now mainly used as a solvent to remove grease from metal parts.

Source of Exposure in Iowa

Most of the trichloroethylene used is released into the atmosphere by evaporation primarily from degreasing operations. Workers who use trichloroethylene in the degreasing industry are exposed to the highest amounts of trichloroethylene. People are exposed to trichloroethylene from many sources, including air, drinking water, and sometimes food. Trichloroethylene can find its way into groundwater and then into public or private drinking water wells from spills, improper disposal, and from leaky storage containers or piping.

Health Effects from Acute or Large Exposures

People who are exposed to large amounts of trichloroethylene can become dizzy or sleepy and may become unconscious if they are exposed to very high levels. Death may occur from inhalation of large amounts of trichloroethylene. Breathing in Some people who get concentrated solutions of trichloroethylene on their skin develop rashes. Toluene can easily cause toxic health effects when inhaled or ingested. Skin absorption occurs more slowly. Breathing in large amounts of trichloroethylene for long periods may cause nerve, kidney, or liver damage.

Health Effects from Smaller, Chronic Exposures

Breathing small amounts of trichloroethylene may cause headaches, lung irritation, dizziness, poor coordination, and difficulty concentrating. Trichloroethylene is reasonably anticipated to be a human carcinogen based upon limited evidence and an association of exposure to trichloroethylene and excess incidences of liver cancer, kidney cancer, and non-Hodgkin’s lymphoma. Pregnant and nursing mothers should avoid exposure to trichloroethylene, as it crosses the placenta and is excreted in breast milk.