Psychiatry and Clinical Psychopharmacology
Original Article

Heavy Metal and Thiol/Disulphide in Children with Attention Deficit and Hyperactivity Disorder


Department of Pediatric Endocrinology, İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, İstanbul, Turkey


Department of Child and Adolescent Psychiatry, Akdeniz University, School of Medicine, Antalya, Turkey


Department of Pediatrics, Bandirma Onyedi Eylül University, Faculty of Medicine, Balikesir, Turkey


Department of Pediatrics, Sakarya University, Faculty of Medicine, Sakarya, Turkey


Department of Pediatric Allergy and Immunology, Sakarya University, Faculty of Medicine, Sakarya, Turkey


Department of Biochemistry, Yıldırım Beyazıt University, Faculty of Medicine, Ankara, Turkey

Psychiatry and Clinical Psychopharmacology 2024; 34: 50-56
DOI: 10.5152/pcp.2023.23724
Read: 129 Downloads: 72 Published: 10 November 2023

Background: In the etiology of Attention Deficit and Hyperactivity Disorder (ADHD), oxidative stress and heavy metal exposure are still controversial topics. In this study, our goal was to examine heavy metal levels and oxidative balance in newly diagnosed patients with ADHD and reveal whether heavy metal levels have an effect on the oxidation balance.

Methods: The study included 35 patients with newly diagnosed ADHD and 31 healthy control groups of similar age and gender. Participants' parents or caregivers completed a semi-structured questionnaire regarding their children's breastfeeding and prenatal and postnatal smoking exposures. The levels of heavy metals lead (Pb), mercury (Hg), and cadmium (Cd) were measured with Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), and a unique automated spectrophotometric approach was used to quantify serum total thiol, native thiol, and disulphide quantities and ratios.

Results: The rate of smoking during pregnancy was significantly higher in the ADHD group than in the control group (p=0.030). Compared to the control group, the native and total thiol levels of children with ADHD were significantly higher (p<0.001). Likewise, the ADHD group had significantly higher Hg levels compared to the control group (p=0.002). Cd levels were substantially greater in the control group compared to the ADHD group (p<0.001). However, there was no significant difference between Pb levels in the ADHD and the control group (p=0.844).  

Conclusion: Exposure to Hg and prenatal smoking may contribute to the development of ADHD in childhood. In response to oxidative stress, the young brains of children with ADHD may enhance their antioxidant levels.

Cite this article as: Bingöl Aydın D, Nasıroğlu S, Aydın E, Elmas B, Özdemir Ö, Erel Ö. Heavy metal and thiol/disulfide in children with attention-deficit and hyperactivity disorder. Psychiatry Clin Psychopharmacol. 2024;34(1):50-56.

EISSN 2475-0581