Iron – It takes just a trace of iron in water to cause trouble. Iron, in amounts of only 0.2 to 0.3 parts per million, can stain plumbing fixtures and laundry. In larger amounts, the water itself may appear rust colored and taste extremely unpleasant.
Cloudy Water – When dissolved in water, some materials create an unappealing cloudiness that is far from the clear liquid most people prefer. Besides being unpleasant to look at and drink, cloudy water may contain minerals or particles which may erode pipes and stain sinks, plumbing fixtures, and clothing.
Naturally Occurring Contaminants – Some contaminating elements may occur naturally in water. These elements include radium, barium, and cadmium.
Man-Made Contaminants – Health-related contaminants from sources such as pesticides, industrial waste, landfills, underground storage tanks, and human and animal waste have been found in some private and public water supplies. When man-made contaminants are found, a local water utility usually brings in the United States Environmental Protection Agency (EPA) to help deal with the problem.