Evaluation of whole blood and urine heavy metals (lead, cadmium) in children with autism spectrum disorder and hyperactivity disorder in Baghdad
Ahmed Swadi1, Hedef El-Yassin1, Mushtaq Hashim2
1 Department of Clinical Biochemistry and 2 Department of Medicine, College of Medicine, University of Baghdad, Baghdad, Iraq
DOI 10.5414/TE500139
Abstract
Objectives: This study aims to measure the concentrations of lead and cadmium in whole blood and urine of children diagnosed with autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), and combined ASD + ADHD, compared with healthy controls in Baghdad, Iraq.
Materials and methods: This case-control study was carried out at the College of Medicine, University of Baghdad, between March and September 2025. A total of 200 children aged 2 – 15 years were enrolled and categorized into four groups: control (n = 40), ADHD (n = 30), ASD (n = 57), and ASD + ADHD (n = 73). Venous blood samples (3 mL) and urine samples (20 mL) were collected from each participant. Whole blood and urinary lead concentrations were measured using flame atomic absorption spectrometry (FAAS), while cadmium concentrations were determined using graphite furnace atomic absorption spectrometry (GFAAS).
Results: The mean concentrations of whole blood lead and cadmium were significantly higher in all patient groups (ASD, ADHD, and ASD + ADHD) relative to controls (p < 0.001). In contrast, urinary cadmium levels did not show significant differences between patient groups and controls (p > 0.05). However, urinary lead concentrations were significantly elevated in all patient groups relative to the control group (p < 0.001).
Conclusion: Elevated whole blood and urinary lead levels, along with increased whole blood cadmium concentrations, suggest that heavy metal exposure may play a role in the pathogenesis of ASD, ADHD, and ASD + ADHD. The absence of significant differences in urinary cadmium indicates limited excretion despite systemic accumulation.
Author Details
Authors
Departments
- 1 Department of Clinical Biochemistry and
- 2 Department of Medicine, College of Medicine, University of Baghdad, Baghdad, Iraq
Address
Ahmed Swadi, PhD candidate
Department of Clinical Biochemistry
College of Medicine, University of Baghdad
Baghdad, Iraq
Email:
[email protected]
Citation
Ahmed Swadi, Hedef El-Yassin, and Mushtaq Hashim.Evaluation of whole blood and urine heavy metals (lead, cadmium) in children with autism spectrum disorder and hyperactivity disorder in Baghdad. 2026; 43: 60-69. doi: 10.5414/TE500139.
