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Drinking Water Contaminants

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SDWIS iconPublic health may be affected adversely if drinking water contaminants are found at levels above federal safety standards. Please note that SDWIS provides the violation and enforcement histories of public water systems, not the chemical analysis and safety of those systems. For this reason, we cannot tell you whether or not your health is at risk from the water in these systems

Microbiological Contaminants

Total Coliform. Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially-harmful, bacteria may be present. Coliforms were found in more samples than allowed and this was a warning of potential problems. More information

Fecal Coliform/E. coli. Fecal coliforms and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, and people with severely compromised immune systems. More information

Turbidity. Turbidity has no health effects. However, turbidity can interfere with disinfection and provide a medium for microbial growth. Turbidity may indicate the presence of disease-causing organisms. These organisms include bacteria, viruses, and parasites that can cause symptoms such as nausea, cramps, diarrhea, and associated headaches. More information

Radioactive Contaminants

Beta/photon emitters. Certain minerals are radioactive and may emit forms of radiation known as photons and beta radiation. Some people who drink water containing beta and photon emitters in excess of the Maximum Contaminant Level over many years may have an increased risk of getting cancer. More information

Alpha emitters. Certain minerals are radioactive and may emit a form of radiation known as alpha radiation. Some people who drink water containing alpha emitters in excess of the Maximum Contaminant Level over many years may have an increased risk of getting cancer. More information

Combined Radium 226/228. Some people who drink water containing radium 226 or 228 in excess of the Maximum Contaminant Level over many years may have an increased risk of getting cancer. More information

Inorganic Contaminants

Antimony. Some people who drink water containing antimony well in excess of the Maximum Contaminant Level over many years could experience increases in blood cholesterol and decreases in blood sugar. More information

Arsenic. Some people who drink water containing arsenic in excess of the Maximum Contaminant Level over many years could experience skin damage or problems with their circulatory system, and may have an increased risk of getting cancer. More information

Asbestos. Some people who drink water containing asbestos in excess of the Maximum Contaminant Level over many years may have an increased risk of developing benign intestinal polyps. More information.

Barium. Some people who drink water containing barium in excess of the Maximum Contaminant Level over many years could experience an increase in their blood pressure. More information

Beryllium. Some people who drink water containing beryllium well in excess of the Maximum Contaminant Level over many years could develop intestinal lesions. More information

Cadmium. Some people who drink water containing cadmium in excess of the Maximum Contaminant Level over many years could experience kidney damage. More information

Chromium. Some people who use water containing chromium well in excess of the Maximum Contaminant Level over many years could experience allergic dermatitis. More information

Copper. Copper is an essential nutrient, but some people who drink water containing copper in excess of the action level over a relatively short amount of time could experience gastrointestinal distress. Some people who drink water containing copper in excess of the action level over many years could suffer liver or kidney damage. People with Wilson's Disease should consult their personal doctor. More information

Cyanide. Some people who drink water containing cyanide well in excess of the Maximum Contaminant Level over many years could experience nerve damage or problems with their thyroid. More information

Fluoride. Some people who drink water containing fluoride in excess of the Maximum Contaminant Level over many years could get bone disease, including pain and tenderness of the bones. Children may get mottled teeth. More information

Lead. Infants and children who drink water containing lead in excess of the action level could experience delays in their physical or mental development. Children could show slight deficits in attention span and learning abilities. Adults who drink this water over many years could develop kidney problems or high blood pressure. More information

Mercury (inorganic). Some people who drink water containing inorganic mercury well in excess of the Maximum Contaminant Level over many years could experience kidney damage. More information

Nitrate. Infants below the age of six months who drink water containing nitrate in excess of the Maximum Contaminant Level could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue-baby syndrome. More information

Nitrite Infants below the age of six months who drink water containing nitrite in excess of the Maximum Contaminant Level could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue-baby syndrome. More information

Selenium. Selenium is an essential nutrient. However, some people who drink water containing selenium in excess of the Maximum Contaminant Level over many years could experience hair or fingernail losses, numbness in fingers or toes, or problems with their circulation. More information

Thallium. Some people who drink water containing thallium in excess of the Maximum Contaminant Level over many years could experience hair loss, changes in their blood, or problems with their kidneys, intestines, or liver. More information

Synthetic Organic Contaminants Including Pesticides and Herbicides

2,4-D. Some people who drink water containing the weed killer 2,4-D well in excess of the Maximum Contaminant Level over many years could experience problems with their kidneys, liver, or adrenal glands. More information

2,4,5-TP (Silvex). Some people who drink water containing silvex in excess of the Maximum Contaminant Level over many years could experience liver problems. More information

Acrylamide. Some people who drink water containing high levels of acrylamide over a long period of time could have problems with their nervous system or blood, and may have an increased risk of getting cancer. More information

Alachlor. Some people who drink water containing alachlor in excess of the Maximum Contaminant Level over many years could have problems with their eyes, liver, kidneys, or spleen, or experience anemia, and may have an increased risk of getting cancer. More information

Atrazine. Some people who drink water containing atrazine well in excess of the Maximum Contaminant Level over many years could experience problems with their cardiovascular system or reproductive difficulties. More information

Benzo(a)pyrene (PAH). Some people who drink water containing benzo(a)pyrene in excess of the Maximum Contaminant Level over many years may experience reproductive difficulties and may have an increased risk of getting cancer. More information

Carbofuran. Some people who drink water containing carbofuran in excess of the Maximum Contaminant Level over many years could experience problems with their blood, or nervous or reproductive systems. More information

Chlordane. Some people who drink water containing chlordane in excess of the Maximum Contaminant Level over many years could experience problems with their liver or nervous system, and may have an increased risk of getting cancer. More information

Dalapon. Some people who drink water containing dalapon well in excess of the Maximum Contaminant Level over many years could experience minor kidney changes. More information

Di (2-ethylext) adipate. Some people who drink water containing di (2-ethylhexyl) adipate well in excess of the Maximum Contaminant Level over many years could experience general toxic effects or reproductive difficulties. More information

Di (2-ethylhexyl) phthalate. Some people who drink water containing di (2-ethylhexyl) phthalate in excess of the Maximum Contaminant Level over many years may have problems with their liver, or experience reproductive difficulties, and may have an increased risk of getting cancer. More information

Dibromochloropropane (DBCP). Some people who drink water containing DBCP in excess of the Maximum Contaminant Level over many years could experience reproductive difficulties and may have an increased risk of getting cancer More information.

Dinoseb. Some people who drink water containing dinoseb well in excess of the Maximum Contaminant Level over many years could experience reproductive difficulties. More information

Dioxin (2,3,7,8-TCDD). Some people who drink water containing dioxin in excess of the Maximum Contaminant Level over many years could experience reproductive difficulties and may have an increased risk of getting cancer. More information

Diquat. Some people who drink water containing diquat in excess of the Maximum Contaminant Level over many years could get cataracts. More information

Endothall. Some people who drink water containing endothall in excess of the Maximum Contaminant Level over many years could experience problems with their stomach or intestines. More information

Endrin. Some people who drink water containing endrin in excess of the Maximum Contaminant Level over many years could experience liver problems. More information

Epichlorohydrin. Some people who drink water containing high levels of epichlorohydrin over a long period of time could experience stomach problems, and may have an increased risk of getting cancer. More information

Ethylene dibromide. Some people who drink water containing ethylene dibromide in excess of the Maximum Contaminant Level over many years could experience problems with their liver, stomach, reproductive system, or kidneys, and may have an increased risk of getting cancer. More information

Glyphosate. Some people who drink water containing glyphosate in excess of the Maximum Contaminant Level over many years could experience problems with their kidneys or reproductive difficulties. More information

Heptachlor. Some people who drink water containing heptachlor in excess of the Maximum Contaminant Level over many years could experience liver damage and may have an increased risk of getting cancer. More information

Heptachlor epoxide. Some people who drink water containing heptachlor epoxide in excess of the Maximum Contaminant Level over many years could experience liver damage, and may have an increased risk of getting cancer. More information

Hexachlorobenzene. Some people who drink water containing hexachlorobenzene in excess of the Maximum Contaminant Level over many years could experience problems with their liver or kidneys, or adverse reproductive effects, and may have an increased risk of getting cancer. More information

Hexachlorocyclopentadiene. Some people who drink water containing hexachlorocyclopentadiene well in excess of the Maximum Contaminant Level over many years could experience problems with their kidneys or stomach. More information

Lindane. Some people who drink water containing lindane in excess of the Maximum Contaminant Level over many years could experience problems with their kidneys or liver. More information

Methoxychlor. Some people who drink water containing methoxychlor in excess of the Maximum Contaminant Level over many years could experience reproductive difficulties. More information

Oxamyl [Vydate]. Some people who drink water containing oxamyl in excess of the Maximum Contaminant Level over many years could experience slight nervous system effects. More information

PCBs [Polychlorinated biphenyls]. Some people who drink water containing PCBs in excess of the Maximum Contaminant Level over many years could experience changes in their skin, problems with their thymus gland, immune deficiencies, or reproductive or nervous system difficulties, and may have an increased risk of getting cancer. More information

Pentachlorophenol. Some people who drink water containing pentachlorophenol in excess of the Maximum Contaminant Level over many years could experience problems with their liver or kidneys, and may have an increased risk of getting cancer. More information

Picloram. Some people who drink water containing picloram in excess of the Maximum Contaminant Level over many years could experience problems with their liver. More information

Simazine. Some people who drink water containing simazine in excess of the Maximum Contaminant Level over many years could experience problems with their blood. More information

Toxaphene. Some people who drink water containing toxaphene in excess of the Maximum Contaminant Level over many years could have problems with their kidneys, liver, or thyroid, and may have an increased risk of getting cancer. More information

Volatile Organic Contaminants

Benzene. Some people who drink water containing benzene in excess of the Maximum Contaminant Level over many years could experience anemia or a decrease in blood platelets, and may have an increased risk of getting cancer. More information

Carbon Tetrachloride. Some people who drink water containing carbon tetrachloride in excess of the Maximum Contaminant Level over many years could experience problems with their liver and may have an increased risk of getting cancer. More information

Chlorobenzene. Some people who drink water containing chlorobenzene in excess of the Maximum Contaminant Level over many years could experience problems with their liver or kidneys. More information

o-Dichlorobenzene. Some people who drink water containing o-dichlorobenzene well in excess of the Maximum Contaminant Level over many years could experience problems with their liver, kidneys, or circulatory systems. More information

p-Dichlorobenzene. Some people who drink water containing p-dichlorobenzene in excess of the Maximum Contaminant Level over many years could experience anemia, damage to their liver, kidneys, or spleen, or changes in their blood. More information

1,2-Dichloroethane. Some people who drink water containing 1,2-dichloroethane in excess of the Maximum Contaminant Level over many years may have an increased risk of getting cancer. More information

1,1-Dichloroethylene. Some people who drink water containing 1,1-dichloroethylene in excess of the Maximum Contaminant Level over many years could experience problems with their liver. More information

cis-1,2-Dichloroethylene. Some people who drink water containing cis-1,2-dichloroethylene in excess of the Maximum Contaminant Level over many years could experience problems with their liver. More information

trans-1,2-Dicholoroethylene. Some people who drink water containing trans-1,2-dichloroethylene well in excess of the Maximum Contaminant Level over many years could experience problems with their liver. More information

Dichloromethane. Some people who drink water containing dichloromethane in excess of the Maximum Contaminant Level over many years could have liver problems and may have an increased risk of getting cancer. More information

1,2-Dichloropropane. Some people who drink water containing 1,2-dichloropropane in excess of the Maximum Contaminant Level over many years may have an increased risk of getting cancer. More information

Ethylbenzene. Some people who drink water containing ethylbenzene well in excess of the Maximum Contaminant Level over many years could experience problems with their liver or kidneys. More information

Styrene. Some people who drink water containing styrene well in excess of the Maximum Contaminant Level over many years could have problems with their liver, kidneys, or circulatory system. More information

Tetrachloroethylene. Some people who drink water containing tetrachloroethylene in excess of the Maximum Contaminant Level over many years could have problems with their liver, and may have an increased risk of getting cancer. More information

1,2,4-Trichlorobenzene. Some people who drink water containing 1,2,4-trichlorobenzene well in excess of the Maximum Contaminant Level over many years could experience changes in their adrenal glands. More information

1,1,1,-Trichloroethane. Some people who drink water containing 1,1,1-trichloroethane in excess of the Maximum Contaminant Level over many years could experience problems with their liver, nervous system, or circulatory system. More information

1,1,2-Trichloroethane. Some people who drink water containing 1,1,2-trichloroethane well in excess of the Maximum Contaminant Level over many years could have problems with their liver, kidneys, or immune systems. More information

Trichloroethylene. Some people who drink water containing trichloroethylene in excess of the Maximum Contaminant Level over many years could experience problems with their liver and may have an increased risk of getting cancer. More information

TTHMs [Total Trihalomethanes]. Some people who drink water containing trihalomethanes in excess of the Maximum Contaminant Level over many years may experience problems with their liver, kidneys, or central nervous systems, and may have an increased risk of getting cancer. More information

Toluene. Some people who drink water containing toluene well in excess of the Maximum Contaminant Level over many years could have problems with their nervous system, kidneys, or liver. More information

Vinyl Chloride. Some people who drink water containing vinyl chloride in excess of the Maximum Contaminant Level over many years may have an increased risk of getting cancer. More information

Xylenes. Some people who drink water containing xylenes in excess of the Maximum Contaminant Level over many years could experience damage to their nervous system. More information