{"title":"Exploring the link between toxic metal exposure and ADHD: a systematic review of pb and hg","authors":"Reyhane Farmani, Omid Mehrpour, Alireza Kooshki, Samaneh Nakhaee","doi":"10.1186/s11689-024-09555-8","DOIUrl":null,"url":null,"abstract":"Attention-Deficit/Hyperactivity Disorder (ADHD) is a recognized neurodevelopmental disorder with a complex, multifactorial origin. Lead (Pb) and mercury (Hg) are highly toxic substances that can potentially impair brain development and have been implicated in the development of ADHD. This systematic review aims to analyze the epidemiological literature regarding the association between Pb and Hg exposure and the diagnosis of ADHD. From November 1983 to June 2, 2023, a comprehensive search was conducted in multiple databases and search engines, including PubMed, Web of Science, Scopus, and Google Scholar. Observational studies (case-control, cohort, and cross-sectional) measuring Pb and Hg levels in various biological samples (blood, hair, urine, nail, saliva, teeth, and bone) of children with ADHD or their parents and their association with ADHD symptoms were included. Out of 2059 studies, 87 met the inclusion criteria and were included in this systematic review. Approximately two-thirds of the 74 studies investigating Pb levels in different biological samples reported associations with at least one subtype of ADHD. However, most studies examining Hg levels in various biological samples found no significant association with any ADHD subtype, although there were variations in exposure periods and diagnostic criteria. The evidence gathered from the included studies supports an association between Pb exposure and the diagnosis of ADHD, while no significant association was found with Hg exposure. Importantly, even low levels of Pb were found to elevate the risk of ADHD. Further research is needed to explore the comprehensive range of risk factors for ADHD in children, considering its significance as a neurodevelopmental disorder.","PeriodicalId":16530,"journal":{"name":"Journal of Neurodevelopmental Disorders","volume":"213 1","pages":""},"PeriodicalIF":4.1000,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Neurodevelopmental Disorders","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1186/s11689-024-09555-8","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CLINICAL NEUROLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Attention-Deficit/Hyperactivity Disorder (ADHD) is a recognized neurodevelopmental disorder with a complex, multifactorial origin. Lead (Pb) and mercury (Hg) are highly toxic substances that can potentially impair brain development and have been implicated in the development of ADHD. This systematic review aims to analyze the epidemiological literature regarding the association between Pb and Hg exposure and the diagnosis of ADHD. From November 1983 to June 2, 2023, a comprehensive search was conducted in multiple databases and search engines, including PubMed, Web of Science, Scopus, and Google Scholar. Observational studies (case-control, cohort, and cross-sectional) measuring Pb and Hg levels in various biological samples (blood, hair, urine, nail, saliva, teeth, and bone) of children with ADHD or their parents and their association with ADHD symptoms were included. Out of 2059 studies, 87 met the inclusion criteria and were included in this systematic review. Approximately two-thirds of the 74 studies investigating Pb levels in different biological samples reported associations with at least one subtype of ADHD. However, most studies examining Hg levels in various biological samples found no significant association with any ADHD subtype, although there were variations in exposure periods and diagnostic criteria. The evidence gathered from the included studies supports an association between Pb exposure and the diagnosis of ADHD, while no significant association was found with Hg exposure. Importantly, even low levels of Pb were found to elevate the risk of ADHD. Further research is needed to explore the comprehensive range of risk factors for ADHD in children, considering its significance as a neurodevelopmental disorder.
期刊介绍:
Journal of Neurodevelopmental Disorders is an open access journal that integrates current, cutting-edge research across a number of disciplines, including neurobiology, genetics, cognitive neuroscience, psychiatry and psychology. The journal’s primary focus is on the pathogenesis of neurodevelopmental disorders including autism, fragile X syndrome, tuberous sclerosis, Turner Syndrome, 22q Deletion Syndrome, Prader-Willi and Angelman Syndrome, Williams syndrome, lysosomal storage diseases, dyslexia, specific language impairment and fetal alcohol syndrome. With the discovery of specific genes underlying neurodevelopmental syndromes, the emergence of powerful tools for studying neural circuitry, and the development of new approaches for exploring molecular mechanisms, interdisciplinary research on the pathogenesis of neurodevelopmental disorders is now increasingly common. Journal of Neurodevelopmental Disorders provides a unique venue for researchers interested in comparing and contrasting mechanisms and characteristics related to the pathogenesis of the full range of neurodevelopmental disorders, sharpening our understanding of the etiology and relevant phenotypes of each condition.