Lead and Cadmium Hair Levels in a Sample of Egyptian Children with Attention Deficit Hyperactivity Disorder

Background: Attention Deficit Hyperactivity Disorder (ADHD) is a common neurobehavioral disorders among children. It has multifactorial mechanisms of induction; one that main mechanism is the exposure to neurotoxins. Environmental exposure to lead (Pb) and cadmium (Cd) may be implicated in its development. Objective: This study estimated the correlation between Pb and Cd hair levels and the development of ADHD. Methods: 102 children were divided into two groups: the ADHD group (n=54) diagnosed with ADHD according to (DSM)-IV, Conner's and intelligence quotient scales, control group apparently healthy children (n=48). Hair samples were taken for estimating Pb and Cd levels using Inductively Coupled Plasma (ICP). Results: A statistically significant difference was found regarding Pb levels between the study and the control groups with significant increased risks among female patients, inattention type and those with severe Conner's scale, meanwhile, Cd neither showed insignificant differences in hair levels nor increased risks among ADHD subtypes or grades of Conner's scale. Conclusion: Both metals showed unexpectedly highly elevated levels in study subjects. Lead has a significant relation with weak association to ADHD meanwhile, cadmium had no significant relation.