Contaminant

Common Sources of Contaminant in Drinking Water

Potential Health Effects from Exposure Above the Maximum Contaminant Level

Asbestos

Decay of asbestos cement in water mains or erosion of natural deposits

Increased risk of developing intestinal polyps

Cadmium

Corrosion of pipes; erosion of natural deposits; runoff of battery and paint waste

Kidney damage

Cyst

Human and animal faecal waste

Gastrointestinal illness

Lead

Corrosion of household plumbing systems; erosion of natural deposits

Kidney problems, high blood pressure; In children, delayed development

Mercury

Erosion of natural deposits; refinery and factory discharge; landfill runoff

Kidney Damage

MTBE

Leaking underground fuel storage tanks, fuel leaching

Effects presently under EPA study

Toxaphene

Runoff/leaching from insecticide used on cotton and cattle

Kidney, liver, or thyroid problems; increased risk of cancer

Turbidity

A measure of the cloudiness of water, turbidity is caused by soil runoff

Organisms in turbid water can cause nausea, cramps, diarrhea, and headaches

VOC (volatile organic compounds)

Agriculture runoff; industrial and chemical discharge

Liver, kidney, stomach or spleen damage, increased risk of cancer, reproductive difficulties