Arsenic is classified chemically as a metalloid, having both properties of a metal and a nonmetal. Arsenic is present naturally in different quantities. It accumulates at high levels in various mineral resources. Specifically, in the ore sources of sulfide ore of copper, lead, zinc, antimony, silver and gold(). However, arsenic is usually found in the environment combined with other elements such as oxygen, chlorine, and sulfur. Arsenic combined with these elements is called inorganic arsenic. Arsenic combined with carbon and hydrogen is referred to as organic arsenic. The concentration of arsenic may be higher in certain areas due to either natural conditions or human activities.