Do Nutritional Deficiencies Increase Susceptibility to Arsenic-Induced Health Effects?

Allan H. Smith, MD, Ph.D.
School of Public Health, University of California, Berkeley
P42ES04705

Background: Arsenic is a naturally occurring metal-like element found widely and in varied forms in the environment. Inorganic forms of arsenic are considered the most toxic and are found in drinking water, soils, and geologic formations. Arsenic is a known carcinogen to humans and skin cancer is the most common form of malignancy; however, other cancers of the lung, bladder, liver, kidney, and prostate can also occur following arsenic exposure. Arsenic is also known to cause a breakdown of the peripheral circulatory system leading to crippling and deforming spontaneous amputations as in blackfoot disease.

There is evidence that suggests that nutritional deficiencies increase susceptibility to arsenic health effects. Scientists at the Superfund Basic Research Program at the University of California Berkeley conducted an epidemiologic study to determine whether nutritional status altered the risk of developing arsenic-induced skin lesions, including pigmentation changes and keratoses. The study was conducted in West Bengal, India, which along with Bangladesh constitutes the largest population of people in the world exposed to arsenic in drinking water.

Advance: Patients with arsenic-induced skin lesions were paired with an age and sex-matched person from a control population. Arsenic exposure from drinking water was similar for both groups. Nutritional assessments were based on interviews of the "senior woman" in each family, who in this population, directs preparation of food for the family. Dietary components were determined from these interviews. Modest increases in risk for skin lesions were related to low intake of animal protein, calcium, fiber, and folic acid.

Implication: The study results suggest that poor nutritional status may play a role in increasing the risk of developing skin lesions in people exposed to arsenic in drinking water. The risk is about double for people with the lowest intake of animal protein, calcium, fiber, and folic acid. The potential protective effects observed in diets adequate for these nutrients were modest and need to be confirmed in other studies. Therefore, prevention efforts should focus foremost on reducing exposure to arsenic.

Citation: Mitra SR, Mazumder DN, Basu A, Block G, Haque R, Samanta S, Ghosh N, Smith MM, von Ehrenstein OS, Smith AH. Nutritional factors and susceptibility to arsenic-caused skin lesions in West Bengal, India. Environ Health Perspect. 2004 Jul;112(10):1104-9.