Arsenic is a common element in the earth’s crust, natural groundwater, and even the human body. It is an odorless and tasteless semi-metal (metalloid) that is naturally present in aquifers throughout the world. Arsenic is typically found as an oxyanion in the environment, most commonly in the +3 and +5 oxidation states. Since 2006, the drinking water standard (maximum contaminant level, or MCL) for arsenic in the U.S. has been 10 ug/L. At concentrations above the MCL, arsenic can cause skin damage, circulatory problems, and an increased risk of cancer.
Many treatment technologies have been developed and refined to remove arsenic from water, including chemical, physical, and biological processes. Typical technologies for arsenic removal are a combination of chemical and physical processes.