Objective: To study the effect of high concentration arsenic in drinking water on children's intelligence.
Methods: Pupils in Hangjinhou Qi were selected as subjects. Arsenic in drinking water and urine was determined. These subjects were divided into control( < 0.05mg/L, group A), mild exposure (0.05 - 0.1mg/L, group B) and heavy exposure group(> or = 0.1 mg/L, group C), according to arsenic concentration in drinking water. The Chinese combined Raven' s test was applied to evaluate the intelligence of children. In addition, the questionnaire survey was conducted to find out information, such as general information of households, source of drinking water, health of subjects and their parents, education of parents, etc.
Results: The boys' average intelligence quotients (IQ) were 99.4 (group A), 96.5 (group B), 94.9 (group C). On the other hand, average IQs of girls were 101.3 (group A), 98.3 (group B) and 94.2 (group C) in the sequence from high to low. When other factors were adjusted, the average intelligence quotient of girls who exposured to arsenic higher than 0.1 mg/L were significantly decreased, compared with control groups, while boys' IQ did not show so.
Conclusion: Children's ingested the dring water contaminating arsenic ( > 1.0mg/L) for the long run probably could have adverse effect on their intelligence development in some degree. Girls' IQ seemed more susceptible to arsenic.