Authors Suggest Kids with Autism May Have a Reduced Ability to Excrete Heavy Metals
Researchers from China have recently conducted a systematic review and meta-analysis of 53 studies that explore the association between exposure to four heavy metals: cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg), and the occurrence of autism spectrum disorder (ASD) in children. The results showed that compared to healthy control groups, ASD groups had significantly higher body burdens of Cd, Pb, As, and Hg. Further subgroup analysis revealed that the concentrations of these four heavy metals were higher in the ASD group, irrespective of testing methods. The review also showed that ASD patients had higher hair and urine concentrations of heavy metals but lower urine concentrations of Pb and arsenic compared to the control group. Based on previous studies, the authors suggest that this finding could be due to ASD patients’ reduced ability to excrete heavy metals. The study also indicated that heavy metal exposure during children’s growth could potentially epigenetically affect DNA methylation and cause oxidative stress and inflammatory response. The authors call on future research to focus on the biological mechanisms of heavy metal exposures inducing ASD. Additionally, the study recommends providing a good diet and reducing heavy metal exposures to prevent ASD in children.