EPA Water Contamination Chart
The following table outlines the possible causes and effects of known water contaminants as described by the U.S. Environmental Protection Agency. To return to Water 101, our guide to common water problems and frequently asked questions about water treatments, click here.
| Contaminant | Possible Effect(s) | Source(s) |
| Asbestos | Cancer | Asbestos cement in water systems |
| Arsenic | Cancer, skin and nervous system toxicity | Pesticides, industrial waste, smelting |
| Barium | Circulatory system effects | Geological |
| Benzene | Cancer | Fuel, drugs, paint, pesticides |
| Cadmium | Kidney effects | Epoxy sealants, spent coal, pigments |
| Carbon Tetrachloride | Cancer | Cleaning solvents |
| Coliform & other bacteria | Gastroenteric infection, dysentery, typhoid fever, and cholera | Human and animal fecal matter |
| Endrin | Liver, kidney and heart damage | Pesticide on insects, rodents and birds |
| Fluoride | Skeletal and dental damage | Fluoridated water, fertilizer and aluminum |
| Giardia lambia | Gastroenteric disease | Human and animal fecal matter |
| Lead | Kidney and nervous system damage | Lead pipes and lead-based solder |
| Legionella | Legionnaire's disease | Natural waters, some water heaters |
| Lindane | Liver, kidney, nervous, immune and circulatory system damage | Insecticide on cattle, cotton and soybeans |
| Mercury | Kidney and nervous system disorders | Crop run-off, batteries |
| Methoxychlor | Growth, liver, kidney and nerve effects | Insecticide on fruits, livestock and pets |
| Nitrate | Blue baby syndrome (methemoglobinemia) | Fertilizer, sewage and animal waste |
| Radon | Cancer | Decay of radionuclides |
| Selenium | Liver damage | Smelting, coal/oil combustion |
| Total Trihalomethanes | Cancer | Surface water treated with chlorine |
| Toxaphene | Cancer | Insecticide on cattle, cotton and soybeans |
| Tetrachloroethylene | Cancer | Dry cleaning materials waste, solvents |
| Turbidity | Interferes with Disinfection, filtration | Erosion, soil run-off and discharges |
| Vinyl Chloride | Cancer | PVC Pipe, solvent breakdown |
Have more question on possible contaminants in your water? If so, please complete our online request form, or call us toll free at (800) 978-5100.