1,1 Dichloroethane (DCE)

DCE is a simple, unsaturated halogenated hydrocarbon. DCE, a liquid at room temperature, is very soluble in organic solvents and is also highly volatile.

Use: DCE does not occur naturally, however, it can be found in landfills as a result of the breakdown of polyvinylidene chloride products. It is produced commercially by the dehydrochlorination of 1,1,2-trichloroethane in the presence of excess base. DCE is used principally for the production of polyvinylidene chloride polymers (PVDC). PVDC is used principally in the food packaging industry as cast and extruded fill (Saran and Velon wraps) and as a barrier coating for paper, cellulose, polypropylene, and other plastics

1,1,1-TCE

1,1,1-Trichloroethane (1,1,1-TCE) is an organic liquid with a chloroform-like odor.

Use: It is largely used as a solvent removing grease from machined metal products, in textile processing and dyeing and in aerosols.

Health Concerns: The MCLG for 1,1,1-TCE has been set at 0.2 parts per million (ppm) because EPA believes this level of protection would not cause any potential health problems. Short-term: EPA has found 1,1,1-TCE to potentially cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time: damage to the liver, nervous system and circulatory system damage. Long Term: 1,1,1-TCE has the potential to cause the following effects from a lifetime exposure at levels above the MCL: liver, nervous system and circulatory system damage.

1,2-DCE

1,2-Dichloroethylene (1,2-DCE) is an odorless organic liquid that has two slightly different forms, a "cis" form and a "trans" form.

Use: Both the cis and trans forms - usually as a mixture - are used as a solvent for waxes and resins; in the extraction of rubber; as a refrigerant; in the manufacture of pharmaceuticals and artificial pearls; in the extraction of oils and fats from fish and meat; and in making other organics.

Health Concern: The MCLGs for 1,2-DCE have been set at 0.07 parts per million (ppm) for the cis form, and 0.1 ppm for the trans form. EPA believes this level of protection would not cause any potential health problems.
Short-Term: EPA has found cis- and trans-1,2-DCE to potentially cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time; central nervous system depression.
Long-Term: Both cis- and trans-1,2-DCE have the potential to cause liver, circulatory and nervous system damage from long-term exposure at levels above the MCL. The trans form is approximately twice as potent as the cis form in its ability to depress the central nervous system.

1,2-Dichloropropane (1,2-DCP)

1,2-DCP is a colorless liquid with a chloroform-like odor. It is soluble in alcohol, ether, benzene and chloroform, and it is miscible with organic solvents. When heated to decomposition, it emits highly toxic fumes of phosgene.

Use: 1,2-DCP is produced by the chlorinating of propylene. Domestic production of isolated 1,2-DCP has been discontinued, although the compound is still in use. 1,2-DCP has been used alone as an insecticide for stored grain, and as a component of several insecticides and nematocidal soil fumigants. Currently, 1,2-DCP is used primarily as a chemical intermediate in the production of carbon tetrachloride and the dry-cleaning agent perchloroethylene.

Health Concern: The PHG of 0.5 ppb was calculated based on the carcinogenic potency of 1,2-DCP. In calculating the PHG, a de minus theoretical excess individual cancer risk level of 10-6 was assumed. The corresponding values for cancer risk levels of 10-5 or 10-4 are 5 and 50 ppb, respectively.

1,2-Dichloroethane (1,2-DCA)

Use: 1,2-DCA is primarily used in the production of vinyl chloride, 1,1,1-Trichloroethane, trichloroethylene, perchloroethylene, aziridines, and ethylene diamines. It is also used as a solvent in cleaning and degreasing industries, a grain fumigant, and is a constituent in varnish removers and scouring compounds.

Health Concern: 1,2-DCA has been identified by US EPA as a probable human carcinogen (B2) and it is listed under the Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65) as a chemical known to the state to cause cancer.

1,2-Dichloropropane

Use: 1,2-Dichloropropane is an organic chemical that can enter drinking water sources through discharges from industrial chemical factories; it is also a primary component of some fumigants.

Health Concern (basis for PHG): 1,2-Dichloropropane causes cancer in laboratory animals and is considered to pose a carcinogenic risk to people.

1,2-Dichlorobenzene (1,2-DCB)

At room temperature, 1,2-DCB is a colorless to pale yellow liquid with a pleasant, aromatic odor. It is miscible with numerous organic solvents including alcohol, ether, benzene and acetone.

Use: The primary uses of 1,2-DCB are as a chemical intermediate and as a solvent. 1,2-DCB is also an insecticide/fumigant used in the control peach tree borers, bark beetles, grubs and termites. Other minor uses include its use as a solvent for waxes, gums, resins, tar, rubbers, oils and asphalt's and as a degreaser for metals, leather and wool.

1,2-Dibromo-3-Chloropropane (DBCP)

DBCP is a simple halogenated hydrocarbon that is a liquid at room temperature. DBCP is miscible in water and alcohol and is also very volatile.

Use: DBCP was originally introduced by the Dow Chemical Company under the trade name Fumazone and by the Shell Development Company under the code number "OS 1897" for use as a soil fumigant for the control of plant parasitic nematodes. The major agriculture use was on soybeans at approximately 12 million pounds per year. In California, the agricultural use of DBCP was suspended in 1977.

1,1-Dichloroethylene

1,1-Dichloroethylene (1,1-DCE) is an organic liquid with a mild, sweet, chloroform-like odor.

Use: Virtually all of it is used in making adhesives, synthetic fibers, refrigerants, food packaging, and coating resins such as the saran types.

Health Concerns: 1,1-DCE can cause liver damage when people are exposed to it at levels above the MCL for relatively short periods of time. A lifetime exposure to 1,1-DCE at levels above the MCL can cause liver and kidney damage, toxicity to a developing fetus, and cancer.

1,3-Dichloropropene (1,3-DCP)

Use: 1,3-DCP, the active ingredient in Telone® II, was introduced in 1945 as a commercial plant soil fumigant for the control of nematode's in various food and nonfood crops.

1,4-Dichlorobenzene (1,40DCB)

1,4-DCB is a chlorinated aromatic compound which is a solid at room temperature, forming colorless to white crystals with an odor of camphor or mothballs.

Use: The primary uses of 1,4DCB are as a space deodorizer, an insecticide fumigant for moths and a chemical intermediate in the production of ployphenylene sulfide resin (a plastic used in electronics applications) and 1,2,4-Trichlorobenzene.

1,2,4-Trichlorobenzene

Use: 1,2,4-Trichlorobenzene is an organic chemical that can enter drinking water sources from a variety of industrial activities.

Health Concern (basis of PHG): 1,2,4-Trichlorobenzene causes adrenal gland enlargement in laboratory animals. An additional 10-fold uncertainty factor was used in determining the PHG, to take into account the potential for carcinogenicity.

1,1,2-Trichloroethylene (TCE)

Use: TCE is an organic chemical used as a solvent and commonly found in discharges from metal degreasing sites, other factories, and dry-cleaning establishments.

Health Concern (basis of PHG): TCE causes cancer in laboratory animals and is considered to pose a carcinogenic risk to people.

2,4-D

2,4-D is a colorless, odorless powder.

Use: It is used as a herbicide for the control of broad-leaf weeds in agriculture, and for control of woody plants along roadsides, railways, and utilities rights of way. It has been most widely used on such crops as wheat and corn, and on pasture and range lands.

Health Concern: The MCLG for 2,4-D has been set at 70 parts per billion (ppb) because EPA believes this level of protection would not cause any potential health problems. Short Term: EPA has found 2,4-D to potentially cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time: Nervous system damage. Long Term: 2,4-D has the potential to cause the following effects from a lifetime exposure at levels above the MCL: Damage to the nervous system, kidneys and liver.

Aluminum (Al)

Aluminum is a member of group III A of the periodic table, with atomic number 13 and atomic weight 26.98. It is the third most abundant element in the earth's crust, comprising 8.3 percent of it's volume. Aluminum has a primary hydration number of six and exists in nature only in the trivalent state.

Use: There are more than 4,000 terminal uses of Al in such fields as electrical engineering and the transport and air traffic industries and in such products as building materials, home furnishings, kitchen appliances, farm implements, containers for packaging material, and building structures. In powder form, Al is a component of paints, pigments, missile fuel, and chemical explosives. Medicinally, Al is widely used in nonprescription antacids and buffered aspirins and Al compounds are used to prevent hyperphosphatemia in patients suffering renal failure.

Antimony

Antimony is a metalloid residing in the forth for of group 5A in the periodic table between arsenic and bismuth.

Use: Historically, antimony in the form of the sulfide has been used as a cosmetic for over 5,000 years, and as a medicinal since at least the 16th century. Antimony in various cosmetic preparations appears to be still used in the third world.

Arsenic

Arsenic is an element that occurs in the earth's crust. Natural sources of exposure include weathering and erosion that deposits arsenic in water bodies where it is taken up by animals and plants.

Use: People may be exposed through food and water, and from industrial sources, where arsenic is used in semiconductor manufacturing, petroleum refining, wood preservatives, animal feed additives, herbicides and insecticides.

Health Concern: Long term exposure to low concentrations of arsenic in drinking water can lead to skin, bladder, lung, and prostate cancer.

Asbestos

Asbestos is the name that's used for a group of six different fibrous minerals (amosite, chrysotile, crocidolite, and the fibrous varieties of tremolite, actinolite, and anthophyllite) that occur naturally in soil and rocks in some areas.

Use: Uses of asbestos were banned in the US by EPA in 1989 because of adverse health effects. The remaining allowed uses of asbestos include battery separators, sealant tape, asbestos thread, packing materials, and certain industrial uses of gaskets.

Health Concerns: Asbestos is a known carcinogen (cancer-causing agent) when the asbestos fibers are inhaled. High levels of exposure to asbestos can cause two types of cancer: cancer of the lung tissue itself and mesothelioma, a cancer of the membrane that surrounds the lung and other internal organs. People who are exposed to lower levels of asbestos may also have an increased risk of developing cancer, but the risks are usually small and are difficult to measure. It is not known whether drinking water containing asbestos causes cancer.

Atrazine

Use: Atrazine is an organic chemical registered for use as an herbicide in California for nonselective weed control along highways and railroad rights-of-way, as well as selective season-long weed control in sorghum, corn and other crops. Other formulations are used as pre-emergent and early post-emergent herbicides for citrus groves, sorghum, and corn.

Health Concern (basis of PHG): Atrazine causes cancer in laboratory animals and is considered to pose a cancer risk to people.

Barium

Barium is a silvery-white metal found in nature, and its compounds can be produced by industry.

Use: Barium compounds are used by the oil and gas industries to make drilling muds. Barium is also used to make paint, bricks, tiles, glass, and rubber.

Health Concern: Barium compounds that do dissolve well in water may cause harmful health effects in people. Ingesting high levels of barium compounds that dissolve well in water over a short time has resulted in: Difficulties in breathing, increased blood pressure, changes in heart rhythm, stomach irritation, brain swelling, muscle weakness, and damage to the liver, heart, kidney, and spleen.

Benzene

Benzene is an unsubstituted, six-carbon aromatic ring.

Use: Benzene is one of the top 20 production chemicals in the United States. Greater than 98 percent of the benzene in the US is produced from petroleum, primarily by companies in the petroleum and petrochemical industries. Benzene has many industrial uses. Roughly 55 percent of the manufactured benzene is used to produce ethylbenzene, an intermediate in the synthesis of styrene which is used to make plastics and elastomers. About 24 percent of the benzene is converted to cumene to produce phenol for the manufacture of phenolic resins, and to acetone, a common solvent.

Health Concern: Exposure to benzene is associated with increases in numerous adverse effects including bone marrow damage, changes in circulating blood cells, developmental and reproductive effects, alterations of the immune system and cancer. Benzene is absorbed through all routes of exposure, and the metabolism and distribution do not appear to depend significantly on route of exposure. In humans, the most sensitive responses to benzene are those related to the blood-forming organs.

Beryllium

Beryllium is a metal found in natural deposits containing other elements, and in some precious stones such as emeralds and aquamarine.

Use: The greatest use of beryllium is in making metal alloys for nuclear reactors and the aerospace industry.

Health Concern: A lifetime of exposure to beryllium in drinking water at levels above the MCL can result in damage to bones, and lungs. It can also cause cancer. This determination is based on animal studies and studies in workers.

Cadmium

Use: Cadmium is an inorganic chemical that can enter drinking water sources from pipe corrosion, erosion of natural deposits, discharge from electroplating and industrial chemical factories, and from metal refineries, as well as runoff from waste batteries and paints.

Health Concern (basis of PHG): Cadmium exposure can cause damage to the kidneys, based on studies of exposed people. It also considered to pose a carcinogenic risk, based on animal studies.

Carbon Tetrachloride

Carbon tetrachloride is the common name for tetrachloromethane, a nonflammable, volatile liquid that has a high vapor density. In liquid form it is clear, colorless, and has a characteristic odor.

Use: Carbon tetrachloride has been used as a dry cleaning agent and fire extinguishing material. It has also been used as a solvent for rubber cement as well as for cleaning equipment and machinery. Further uses include those of a refrigerant and as a feedstock chemical for fluorocarbon propellants. In 1986, fumigation by carbon tetrachloride was banned in the United States except for the preservation of museum artifacts.

Chromium

Use: Chromium is an inorganic chemical that can enter drinking water sources through discharges from steel and pulp mills and chrome plating, leaching from hazardous waste sites, and erosion of natural deposits.

Health Concern (basis of PHG): Chromium may be present in drinking water sources in two oxidation states: Chromium III and VI. Chromium III contributes to human nutrition and is considered relatively innocuous as a drinking water contaminant. Chromium VI is assumed by OEHHA to pose a carcinogenic risk when ingested.

Copper

Copper is a metal found in natural deposits as ores containing other elements. Since copper contamination generally occurs from corrosion of household copper pipes, it cannot be directly detected or removed by the water system.

Use: Copper is widely used in household plumbing materials.

Health Concern: Short- and Long-term effects: Copper is an essential nutrient, required by the body in very small amounts. The MCLG for copper has been set at 1.3 parts per million (ppm) because EPA believes this level of protection would not cause any potential health problems. However, EPA has found copper to potentially cause the following health effects when people are exposed to it at levels above the Action Level for relatively short periods of time: stomach and intestinal distress, liver and kidney damage, and anemia. Persons with Wilsons disease may be more sensitive than others to the effects of copper contamination.

Cyanide

Use: Cyanide is an inorganic chemical that can enter drinking water sources from discharges from steel/metal, plastic or fertilizer factories.

Health Concern (basis of PHG): The PHG is based on an absence of clinical and histopathological effects in laboratory animals. Effects are related to the inhibition of cellular respiration resulting in cellular hypoxia, to which the central nervous system and heart are particularly susceptible.

Dalapon

Dalapon is a colorless liquid with an acrid odor sold as sodium or magnesium salt.

Use: Dalapon is a herbicide used to control grasses in a wide variety of crops, including fruit trees, beans, coffee, corn, cotton and peas. It is also registered for use in a number of non-crop applications such as lawns, drainage ditches, along railroad tracks, and in industrial areas.

Health Concerns: Dalapon is not known to have any short-term effects. However, over a lifetime exposure at levels above the MCL, dalapon can cause increased kidney-to-body weight. There is not enough evidence to determine whether dalapon can cause cancer from lifetime exposure in drinking water.

Di(2-Ethylhexyl)Phthalate (DEHP)

Use: DEHP is a phthalic acid ester used primarily as a plasticizing additive in the production of polyvinyl chloride resins.

Health Concern (basis of PHG): DEHP causes cancer in laboratory animals and is considered to pose a carcinogenic risk to people.

Dichloromethane

Dichloromethane (DCM) is a colorless organic liquid with a sweet, chloroform-like odor.

Use: The greatest use of DCM is as a paint remover. Other uses include: solvent and cleaning agent in a variety of industries, a fumigant for strawberries and grains; and to extract substances from foodstuffs.

Health Concerns: The MCLG for dichloromethane has been set at zero because EPA believes this level of protection would not cause any potential health problems. Short Term: EPA has found dichloromethane to potentially cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time: Damage to the nervous system and to blood. Long Term: Dichloromethane has the potential to cause the following effects from a lifetime exposure at levels above the MCL: liver damage; cancer.

Ethylbenzene

Use: Ethylbenzene is a widely used industrial solvent that can enter drinking water sources through discharges from petroleum refineries or industrial chemical factories.

Health Concern (basis of PHG): Ethylbenzene causes liver toxicity in laboratory animals. The PHG contains an additional 10-fold uncertainty factor to take into account possible carcinogenicity.

Ethylene Dibromide

Ethylene dibromide (EDB) is a colorless, heavy organic liquid with a mildly sweet chloroform-like odor.

Use: EDB is mainly used in antiknock gasoline mixtures, particularly in aviation fuel.

Health Concern: EDB can cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time: Damage to the liver, stomach, and adrenal glands. Also significant reproductive system toxicity, particularly in the testes. A lifetime exposure to EDB at levels above the MCL can cause the following effects: Damage to the respiratory system, nervous system, liver, heart, kidneys, and it can even cause cancer.

Fluoride

Many Consumer Confidence Reports list fluoride among the substances found in drinking water. That's because fluoride is present in the water naturally, and because many community water systems deliberately add fluoride to the water to improve dental health.

Use: Studies have consistently indicated that fluoridation is safe and is the most cost effective and practical means for reducing the incidence of dental caries (tooth decay) in a community. However, the oral health benefits are reduced if the optimal level of fluoride (approx. 1 ppm) is not maintained.

Mercury (Inorganic)

Mercury is an element with an atomic number of 80 on the periodic table, which is currently found in the earth's crust with an average content of 0.5 ppm. Most of the world's supply of mercury is produced from mercury mines; both open air and underground mines. Most mercury mining in the US is done secondarily to other mining.

Use: Mercury is a very useful component of many items due to its unique properties. It exhibits fluidity at a wide range of temperatures, and a uniform volume expansion over the entire liquid temperature range; thus, it is used in thermometers and other monitoring equipment. It has a high ability to form alloys with many metals, thus its significance use in dental amalgams, which are composed of nearly 50% elemental mercury combined with other metals. Conductivity properties have made mercury an essential component in batteries and switching and wiring devices. Mercury is used in lamps for its high efficiency, long life and high lumen output.

Methoxychlor

Use: Methoxychlor is an insecticide used on fruits and alfalfa that can enter drinking water sources through runoff or leaching.

Health Concern (basis of PHG): Health effects associated with methoxychlor are reproductive difficulties.

Nickel

Elemental nickel, Ni, is a member of the Group VIII transition metal series. Nickel may exist in a number of oxidation states. A large number of nickel compounds have been identified and characterized; many of them, such as nickel sulfate, nickel nitrate, nickel chloride, and nickel acetate are relatively soluble in water. Nickel is a natural occurring element; it is neither created nor destroyed by human activities. It is a commercially important metal because of its hardness, strength and resistance to corrosion.

Use: Primary nickel is produced by the mining and smelting of nickel ores. More than 80% of all nickel is used in it's metallic form, principally as nickel-alloys. Nickel is widely used in aircraft and boat manufacturing. Nickel-containing stainless and alloy steels are used in aircraft frames; nickel based supperalloys are used for aircraft parts such as jet engines, gas turbines, and turbosuperchargers. In ships and boats, nickel alloys and copper-nickel alloys are used in parts exposed to saltwater such as the hulls, propellers and pumps. Nickel is also used in making coins, jewelry, catalysts, magnets, batteries, and color pigments.

Health Concern: Nickel is a natural occurring element and is ubiquitous in the environment; it has been detected in surface water, groundwater, air, soil and food. Nickel compounds can be divided into two broad categories, those that are soluble in water and those that are not soluble in water. Single or repeated oral administration of soluble nickel compounds to experimental animals produced adverse effects mainly on the kidney, lung and the immune and endocrine systems.

MTBE

MTBE (Methyl-tert-butyl ether) is a member of a group of chemicals commonly known as fuel oxygenates. Oxygenates are added to the fuel to increase its oxygen content. It is a flammable liquid with a distinctive, disagreeable odor, MTBE is made from blending chemicals such as isobutylene and methanol, and has been used since the 1980's instead of lead to achieve more efficient burning.

Use: MTBE is used in gasoline throughout the US to reduce carbon monoxide and ozone levels caused by auto emissions.

Health Concern: There is no data available on the effects on people from drinking MTBE. There is no evidence that MTBE causes cancer in humans, although animal studies have found that breathing high levels of MTBE for long periods may cause kidney or liver cancer.

Nitrates/Nitrites

Nitrates and nitrites are nitrogen-oxygen chemical units that combine with various organic and inorganic compounds. Once taken into the body, nitrates are converted into nitrites.

Use: The greatest use of nitrates is as a fertilizer.

Health Concerns: Excessive levels of nitrate in drinking water have caused serious illness and sometimes death. The serious illness in infants is due to the body's conversion of nitrate to nitrite, which can interfere with the oxygen-carrying capacity of the child's blood. This can be an acute condition in which health deteriorates rapidly over a period of days. Symptoms include shortness of breath and blue skin. A lifetime exposure to nitrates and nitrites at levels above the MCL can cause diuresis, increased starchy deposits, and hemorrhaging of the spleen.

Oxamyl

Use: Oxamyl can enter drinking water sources through runoff and leaching of insecticides used on field crops, fruits, ornamentals and especially on apples, potatoes, and tomatoes.

Health Concern (basis of PHG): The PHG is based on decreased body weight gain in chronically-exposed laboratory animals.

Thallium

Use: Thallium is an inorganic chemical that can enter drinking water sources through leaching from ore-processing sites or discharges from electronics, glass or drug factories.

Health Concern (basis of PHG): Hair loss in laboratory animals—indicative of thallium toxicity—is the endpoint used in establishing the PHG. Health effects associated with thallium exposure include changes in blood parameters, and at higher levels, kidney, liver or intestinal problems.

Selenium

Selenium is a metal commonly found in rocks and soil.

Use: The greatest use of selenium compounds is in electronic and photocopier components, but they are also widely used in glass, pigments, rubber, metal alloys, textiles, petroleum, medical therapeutic agents, and photographic emulsions.

Health Concerns: The EPA believes that other selenium compounds are not classifiable with regard to their carcinogenicity. Studies of laboratory animals and people show that most selenium compounds probably do not cause cancer.

Silvex

2,4,5-TP is a white organic powder with little odor. Its use has been banned since 1985.

Use: The greatest use of 2,4,5-TP was as a postemergence herbicide for control of woody plants, and broadleaf herbaceous weeds in rice and bluegrass turf, in sugarcane, in rangeland improvement programs, and on lawns.

Health Concerns: The MCLG for 2,4,5-TP has been set at .05 parts per million (ppm) because EPA believes this level of protection would not cause any potential health problems. Short-term: EPA has found 2,4,5-TP to potentially cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time: depression and other nervous system effects, weakness, stomach irritation and minor damage to liver and kidneys. Long-term: 2,4,5-Tp has the potential to cause the following effects from a lifetime exposure at levels above the MCL: minor kidney damage.

Simazine

Simazine is an organic white solid.

Use: Simazine is used as a pre-emergence herbicide used for control of broad-leaved and grassy weeds on a variety of deep-rooted crops such as artichokes, asparagus, berry crops, broad beans, citrus, etc., and on non-crop areas such as farm ponds and fish hatcheries.

Health Concerns: Simazine can cause weight loss and changes in blood when people are exposed to it at levels above the MCL for relatively short periods of time. A lifetime exposure to simazine at levels above the MCL can cause: Tremors, damage to testes, kidneys, liver, and thyroid, also gene mutation, and cancer.

Styrene

Styrene is an oily organic liquid with an aromatic, almost floral odor.

Use: Initially, styrene was used primarily in the synthetic rubber industry, but it is currently used as a building block for polymers in making plastics, resins, and paints.

Health Concerns: The MCLG for styrene has been set at 0.1 parts per million (ppm) because EPA believes this level of protection would not cause any potential health problems. Short-Term: EPA has found styrene to potentially cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time: nervous system effects such as depression, loss of concentration, weakness, fatigue and nausea. Long-Term: Styrene has the potential to cause the following effects from a lifetime exposure at levels above the MCL: liver and nerve tissue damage; cancer.

Tetrachloroethylene

Tetrachoroethylene is a manufactured chemical that is a nonflammable liquid at room temperature. It evaporates easily into the air and has a sharp, sweet odor.

Use: It is widely used for dry cleaning of fabrics and for metal-degreasing.

Health Concerns: The health effects of breathing in air or drinking water contaminated with low levels of tetrachloroethylene are not known. The Department of Health and Human Services has determined that tetrachloroethylene may reasonably be anticipated to be a carcinogen. Tetrachloroethylene has been shown to cause liver tumors in mice and kidney tumors in male rats.

Toluene

Toluene is an organic liquid with a sweet, benzene-like odor.

Use: The largest chemical use for toluene is to make benzene and urethane.

Health Concerns: The MCLG for toluene has been set at 1 parts per million (ppm) because EPA believes this level of protection would not cause any potential health problems. Short-Term: EPA has found toluene to potentially cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time: minor nervous system disorders such as fatigue, nausea, weakness, confusion. Long-Term: Toluene has the potential to cause the following effects from a lifetime exposure at levels above the MCL: more pronounced nervous disorders such as spasms, tremors, impairment of speech, hearing, vision, memory, coordination; liver and kidney damage.

Vinyl Chloride

Vinyl chloride is a colorless organic gas with a sweet odor.

Use: It is a manufactured substance that is used to make polyvinyl chloride (PVC). PVC is used to make a variety of plastic products, including pipes, wire and cable coatings, and furniture upholstery.

Health Concerns: The effects of drinking high levels of vinyl chloride are unknown. The Department of Health and Human Services has determined that vinyl chloride is a known human carcinogen. Vinyl chloride exposure results in liver cancer in people.

Xylene

A xylene is any of a group of very similar organic compounds. They are clear liquids with a sweet odor.

Use: The greatest use of xylenes is as a solvent which is much safer than benzene. Other uses include: in gasoline as part of the BTX component (Benzene-toluene-xylene); Xylene mixtures are used to make phthalate plasticizes, polyester fiber, film and fabricated items.

Health Concerns: The MCLG for xylenes has been set at 10 parts per million (ppm) because EPA believes this level of protection would not cause any potential health problems.
Short-Term: EPA has found xylenes to potentially cause the following health effects when people are exposed to it at levels above the MCL for relatively short periods of time: disturbances of cognitive abilities, balance, and coordination.
Long Term: Xylenes have the potential to cause the following effects from a lifetime exposure at levels above the MCL: damage to the central nervous system, liver and kidneys.