Lead exposure and behavior among young children in Chennai, India.

Lead exposure has long been associated with deficits in IQ among children. However, few studies have assessed the impact of lead on specific domains of behavior and cognition. We evaluated the associations between lead and different domains of neurobehavior and their relative sensitivity to lead. We determined blood lead levels using a LeadCare instrument in 756 children 3-7 years of age attending pre- and elementary schools in Chennai, India. Anxiety, social problems, inattention, hyperactivity, and attention deficit hyperactivity disorder (ADHD), as well as executive function were assessed in children by their schoolteachers using Conners' Teacher Rating Scales-39, Conners' ADHD/Diagnostic and Statistical Manual for Mental Disorders, 4th Edition Scales (CADS), and the Behavior Rating Inventory of Executive Function questionnaires, with higher scores denoting worse behavior. Analyses were carried out using multivariate generalized estimating equations with comparisons of outcome Z-scores to assess the relative strengths of the associations between log-blood lead and the different domains of behavior. Mean blood lead level was 11.4 +/- 5.3 microg/dL. Blood lead was associated with higher anxiety (beta = 0.27, p = 0.01), social ...Continue Reading