Urinary Arsenic Levels Correlate with Decrements in Intelligence Scores in Bengalese Children
Allan H. Smith MD, Ph.D. School of Public Health, University of California Berkeley P42ES004705
Research findings from the laboratory of NIEHS grantee Allan Smith at the University of California Berkeley demonstrate adverse effects on children’s intellectual function and intelligence associated with urinary arsenic levels.
The study was carried out in West Bengal, India, a region known for high levels of arsenic in ground water. Three hundred fifty-one children were given a series of intelligence tests thought to be culturally appropriate that could span a variety of lifestyles and languages in rural West Bengal. Urinary arsenic was measured along with ground water arsenic in all wells these children or their mothers had drunk from in the children’s lifetimes. The children were divided into three groups according to high, medium, and low urinary arsenic. The intelligence test results showed a decline of 12 percent for a vocabulary test, 21 percent for an object assembly test, and 13 percent in a picture completion test for the children in the high urinary arsenic group. These findings were similar to another NIEHS-supported arsenic study by Joseph Graziano and colleagues at Columbia University conducted in a population of children in neighboring Bangladesh.
Acute neurotoxic effects of arsenic have been well documented and include short-term memory loss and problems in learning and concentration. Children are known to be particularly susceptible to the neurotoxic effects of other metals, especially lead and mercury. Limited evidence from animal studies and earlier studies in children gave some indication that arsenic is associated with neurodevelopmental delays. The current findings need to be confirmed; however, they add to the body of knowledge of the adverse health effects of arsenic in children.
Citation: von Ehrenstein OS, Poddar S, Yuan Y, Mazumder DG, Eskenazi B, Basu A, Hira-Smith M, Ghosh N, Lahiri S, Haque R, Ghosh A, Kalman D, Das S, Smith AH. Children's intellectual function in relation to arsenic exposure. Epidemiology. 2007 Jan;18(1):44-51.