The Effect of High Sulfur Content in Tap Water

If you turn on the water in your home and it smells like rotten eggs, it is a safe bet that you have a high sulfur count in your water. Sulfur is a mineral that exists naturally in groundwater, since rain and surface water seeps through rocks in the earth and picks up minerals present in the rocks. It is one of the minerals that is measured during a water quality test.

History

• Sulfur is not a regulated contaminant. No official minimum or maximum safe levels exist. The Environmental Protection Agency has a dinking water standard for sulfate of 250 milligrams per liter (mg/L), but this is primarily in place because concentrations higher than that will cause changes in odor and taste. Although people and animals adjust to the taste and smell of water with high sulfur content, it does affect the taste of any food and beverages prepared with it.

Effects

• There does not seem to be any long-term health risks associated with high sulfur water for adults. Most people experience diarrhea, dehydration and other gastro-intestinal issues when they first consume this water, but the effects wear off over time. Infants and small children are more affected by the diarrhea than adults are; but even for them, the effects are not major. The Food and Nutrition Board also noted an association between high sulfur content and ulcerative colitis risk, but stated that the relationship has not been thoroughly evaluated enough to merit an intake limit.

Significance

• Water with concentrations over 250 mg/L are considered by the EPA to have high sulfur levels. Most public water supplies have concentrations of less than 500 mg/L, though some higher concentrations have been found in communities close to mines, due to mine runoff affecting the water supply. In cases like this, many people switch to bottled or filtered water due to the taste. However, even in cases where sulfur levels of over 1,000 mg/L have been recorded, people have been able to adapt.

Considerations

• High sulfur content in water has a corrosive effect on metal pipes, such as those made of copper, steel and iron, and can damage water heaters. Scale buildup from the sulfur can clog pipes and affect water flow, eventually requiring pipe replacement. In cases like these, plastic pipe may be a better solution. Sulfur also causes a black slime to form inside water heaters and water softening systems, which stains sinks, tubs, washers and clothing either yellow or black. The sulfur-loving bacteria that make their home in high sulfur content water cause this.

Prevention/Solution

• The best way to combat high sulfur content is with a water filtration system like reverse osmosis or ion exchange. These systems remove sulfur from the water and, while they are effective, they are slow and can waste water. Unless the concentration is so high as to cause an objectionable smell, most people choose to use bottled water for drinking and cooking and use the sulfur water for washing and household use, if they do anything at all.