Drinking Water Contaminant: Arsenic
Arsenic and Your Health: What are the health effects of arsenic in drinking water?
Arsenic is a toxic chemical element that is naturally found in the Earth's crust, in soil, rocks, and minerals. It can also be released into the environment from agricultural and industrial activities. Arsenic can enter drinking water through the ground or as run-off into surface water sources. It occurs naturally in the groundwater in New Mexico because the water dissolves it out of volcanic rocks and soil. There is a wide variation in the levels of arsenic found in drinking water systems and private water supplies across New Mexico.
Drinking water with high levels of arsenic over many years can cause health problems. Arsenic in drinking water is absorbed from the gastrointestinal tract (gut) and widely spread within the body. Most of this arsenic can be filtered out through the kidneys and eliminated from the body within a few days.
People who drink water containing arsenic in excess of EPA's standard and over many years could experience skin, cardiovascular, neurological, liver, and kidney problems; they also have an increased risk of diabetes and cancer. Studies have shown that exposure over many years to high levels of arsenic in drinking water can increase a person’s risk of certain cancers, diabetes, arterial thickening (which leads to hypertension), liver damage, peripheral nervous system damage (such as sensation of pins and needles in hands and feet), peripheral vascular disease, and skin changes.
Several studies have shown that arsenic in drinking water can increase the risk of some cancers such as bladder, lung, skin, kidney, prostate and liver cancers. Learn more about cancers in New Mexico.
In 2001 the EPA reduced the regulatory drinking water standard (Maximum Contaminant Level) from 50 parts per billion (ppb) to 10 ppb on the basis of bladder and lung cancer risks.
Reducing Arsenic in Drinking Water (566.2 KB)
For more information on arsenic, including where it comes from, how you can be exposed to it, and the type of health effects it can have, see this
U.S. Environmental Protection Agency (EPA) fact sheet. (268.2 KB)
For more scientific information on arsenic see this
ATSDR (Agency for Toxic Substances and Disease Registry) document. (118.5 KB)
back to top
Monitoring Requirements for Arsenic
All community water systems are required to monitor for arsenic at the entry-point to the distribution system. However, the frequency of monitoring varies based on source water type and the level of arsenic observed in past samples. Routine, required monitoring is annual for surface water sources and once every three years for ground water sources of drinking water, with quarterly monitoring if a sample exceeds 10 parts per billion (ppb). With a state-granted monitoring waiver, the sampling frequency can be reduced to once every nine years.
For more information on monitoring requirements and the arsenic rule, see the following quick references on the monitoring framework and arsenic rule.
back to top
The first step in preventing exposure to arsenic from your drinking water is testing your water.
If your water comes from a municipal or privately-owned water company that meets the definition of a community water system, they are already testing for arsenic in your water. If you have a water from a community water supply, contact your community water system to learn about levels and recent testing or the New Mexico Environment Department Drinking Water Bureau at 1-877-654-8720.
If you drink water from a private well, you may want to have it tested periodically for levels of arsenic and other metals or contaminants.
You can remove the arsenic to a safe level through reverse osmosis units for all water you drink and cook with. Reverse osmosis units typically remove arsenic from drinking water whereas other types of filtration may not. If you decide to purchase a reverse osmosis system you may want to consult with National Sanitation Foundation at toll-free at 1-877-867-3435 to help make a decision of which model to buy.
Contact the New Mexico health department Toll Free at 1-888-878-8992 to find out whether arsenic is a contaminant of concern in your area. The state Drinking Water Bureau can give you names of laboratories that are certified to test drinking water; call Toll Free 1-877-654-8720.
Find certified home treatment units on the following Web sites.
Drinking Water Quality
Community Water System (CWS) Data
back to top