Evaluation of Blood Lead Level as a Risk Factor in Children with Autism Spectrum Disorder: A Case Control Study

Abstract

The present study deals with the Evaluation of Blood lead (Pb) level as a risk factor in Autistic Children and to determine the association between blood lead level (BLL) and Autism Spectrum Disorder (ASD). It was a casecontrol study. Blood samples were collected from both case (25 of 3-16 years) and control (25 of 3-16 years) groups by vein puncture for the determination of blood lead levels using Energy Dispersive X-ray Fluorescence (EDXRF) technique. Predesigned questionnaires were completed for each case and control group by interviewing the parents or care-givers. The present study revealed that there was a significant difference between mean ages of mother at child’s birth in both case and control group. Significantly more children in case group had parents with higher educational levels and came from families with higher socioeconomic status. Significantly more children in ASD group came from urban areas than rural area. The risk of exposure to air pollution in case group was 14 times more than the control group which is represented by the proximity of child’s residence to high traffic roads. History of pica was exclusively present in case group (p value 0.001) indicating that children in ASD group had more exposure to lead than those of control group. The mean blood levels were 44.18 and 29.22 μg/dl for case and control group respectively. In case group 48% of the children had blood lead level ≥ 10 μg/dl compared to 24% in the control group.