Arsenic (As) is a metalloid element that is naturally present in both organic and inorganic forms. Inorganic arsenic is a naturally-occurring groundwater contaminant in some geographical regions and can also be used as a wood preservative, in the form of arsenic trioxide. Arsenic is used as an alloying agent, and industrial uses range from the production of feed additives, fertilizers, herbicides, and insecticides to processing of materials like glass, paper, and textiles (ATSDR 2007, WHO 2016). Organic arsenic can be converted to the more toxic inorganic form when it is ingested and also can be found in seafood or food grown using contaminated groundwater (WHO 2016).


Health Effects:

Inorganic and organic forms of arsenic have different toxicities. Very little is known about organic arsenic exposure, however, animal testing has suggested that acute ingestion may lead to diarrhea and chronic exposure may lead to kidney damage. The effects of inorganic arsenic, which is more toxic than organic arsenic, may vary symptomatically depending on level and route of exposure. Some of the following may apply:

  • Inorganic arsenic is a known human carcinogen. There is strong evidence that it is linked to lung, skin, and bladder cancer (ATSDR 2007, Celik 2008).

  • Inorganic arsenic may also cause skin irritation, skin color changes, blood disorders, cardiovascular diseases, and hormone disruption (ATSDR 2007).

  • Preliminary data suggest that inorganic arsenic may interfere with normal fetal development (Vahter 2009) and cause deficits in brain development and intelligence (Wasserman 2004).

  • Preliminary studies have correlated type 2 diabetes with low-level arsenic consumption, implying that drinking low levels of arsenic may lead to type 2 diabetes (Navas-Acien 2008).



ATSDR. ToxGuide for Arsenic. (Center for Disease Control and Prevention, 2007).

Celik, I. et al. Arsenic in drinking water and lung cancer: A systematic review. Environ. Res. 108, 48–55 (2008).

Navas-Acien, A., Silbergeld, E. K., Pastor-Barriuso, R. & Guallar, E. Arsenic exposure and prevalence of type 2 diabetes in US adults. J. Am. Med. Assoc. 300, 814–822 (2008).

Niedzwiecki, M. M. et al. A dose-response study of arsenic exposure and global methylation of peripheral blood mononuclear cell DNA in Bangladeshi adults. Environ. Health Perspect. 121, 1306–1312 (2013).

Vahter, M. Effects of arsenic on maternal and fetal health. Annu. Rev. Nutr. 29, 381–399 (2009).

WHO. Arsenic: Fact Sheet. (World Health Organization, 2006).

Published on September 27, 2016

IMPORTANT NOTE: ratings do not provide a measure of health risk or chemical exposure associated with any individual product, or any individual element or related chemical.