Environmental sources of arsenic exposure include food, water, soil, and air. Arsenic is strongly associated with lung, bladder, and skin cancer in humans. Skin lesions, peripheral neuropathy, and anemia are hallmarks of chronic arsenic ingestion. With the exception of the electronics industry, commercial use of arsenic is declining.

Arsenic is ubiquitous in the environment. Potential sources of arsenic exposure include

• Groundwater: The areas in the United States with the highest natural groundwater concentrations of arsenic are the Southwest, the Northwest, Alaska, and other areas near geothermal activity.  For more information on arsenic in groundwater, visit the U.S. Geological Survey, Arsenic in ground water of the United States web site.
• Commercial products: wood preservatives, insecticides, cattle and sheep dips, etc.

• Food: wine and tobacco (plants sprayed with arsenic-containing pesticides, for more information see GAO report titled Pesticides on Tobacco), and seafood (especially bivalves, certain cold water and bottom-feeding finfish, and seaweed). Fish arsenic has low toxicity to humans and is rapidly excreted in urine.
• Industrial processes and smelting metal ores.
• Medicinals: Fowler's solution (potassium arsenite), folk remedies ("Asiatic pill," kushtay, yellow root), kelp-containing health foods, some naturopathic remedies.

Source:  Agency for Toxic Substances and Disease Registry, Case Studies in Environmental Medicine Arsenic Toxicity, October, 2011.