Arsenic occurs naturally in the environment and plants. Activities such as volcanic action, erosion of rocks, forest fires, and human agricultural and industrial activities promote arsenic contamination of the environment. Arsenic subsequently gets into drinking water through ground and surface water sources. Arsenic contamination in drinking water is still a problem in many developing and undeveloped countries.
Human exposure to arsenic can cause various types of cancers, such as bladder, lungs, skin, kidneys, nasal passage, liver, and prostate. Other effects of long term arsenic exposure include stomach pain, vomiting, diarrhea, as well as numbness in hands and feet, partial paralysis, and even blindness. The World Health Organization (WHO) has placed arsenic in on the top 10 list of chemicals that are life threatening.