Relationship between attention deficit hyperactivity disorder and the various elements in hair among Mongolian children in Baotou

Objective To explore possible relation between attention deficit hyperactivity disorder with multiple elements in hair among Mongolian students from Inner Mongolia.Methods A total of 1 000 students (460 boys and 540 girls) from three Mongolian primary schools were investigated.The Conners Child Behavior Checklist (teacher report version) was used to assess attention deficit hyperactivity disorder (ADHD) according to Diagnostic and Statistical Manual of Mental Disorders Revised Edition (DSMⅣ).Control healthy students were selected from the same grade,same sex.Hair copper,zinc,manganese,lead,cadmium,arsenic,mercury,selenium level was assessed.Results Prevalence of ADHD was 3.8%(n =38),with 30 boys.Significant differences were found by grades (grade 2 to grade 6:0.2%,0.3%,0.8%,1.3%,1.2%,x2=12.824,P<0.05).Hair copper and lead in children with ADHD was higher than healthy group(t =-2.814,-4.785,P<0.05),hair cadmium and copper zinc ratio was found higher in ADHD students(t=-3.627,-4.117,P<0.05).Hair zinc was lower than the healthy group(t =2.105,P<0.05).Conclusion Attention deficit hyperactivity disorder is high among Mongolian boys and high grades in primary school.Hair copper,lead,cadmium and copper zinc ratio is higher among attention deficit hyperactivity disorder children.