Arsenic is an odorless and tasteless semimetal element. It occurs naturally and is a byproduct of some agricultural and industrial activities. Higher levels tend to be found in ground water sources than in surface water.
Human exposure can lead to short- and long-term health effects. Long-term exposure has been linked to some forms of cancer. Short-term exposure to high levels (1000 times higher than the EPA limit) can lead to adverse health effect, such as nausea and vomiting, but such an exposure is highly unlikely from a Public Water System (PWS) in compliance with U.S. Environmental Protection Agency (EPA) regulations.
The EPA has set the current Maximum Contaminant Level (MCL) of arsenic at 10 parts per billion (ppb). This would equate to roughly a few drops of food coloring in an Olympic-sized swimming pool.
Des Moines Water Works (DMWW) sees very low levels, at or below quantitation limits, of arsenic in our source waters. DMWW’s three treatment plants all have treatment processes in place that remove over 90% of arsenic from the source waters. This ensures that DMWW finished drinking water is well below the EPA’s MCL for arsenic. According to the Iowa Department of Natural Resources, the enforcement agency of water regulations for the EPA, only 0.3% of PWS in Iowa had arsenic violations in 2010.
Should you be worried about arsenic in your water? If you receive water from a Public Water System, they are already testing for it and will list levels detected in the Consumer Confidence Report they are required to provide every year. If the MCL is violated, the Public Water System must provide a public notice.
If you have your own water supply and are concerned about arsenic or other contaminants DMWW provides testing services for nominal fees. If you have questions about your drinking water, please contact DMWW at 515.283.8700.