Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Jan 29;16(3):382.
doi: 10.3390/ijerph16030382.

The Association between Lead and Attention-Deficit/Hyperactivity Disorder: A Systematic Review

Gabriele Donzelli  1   2 , Annalaura Carducci  3 , Agustin Llopis-Gonzalez  4   5 , Marco Verani  6 , Agustin Llopis-Morales  7 , Lorenzo Cioni  8 , María Morales-Suárez-Varela  9   10
Affiliations

The Association between Lead and Attention-Deficit/Hyperactivity Disorder: A Systematic Review

Gabriele Donzelli et al. Int J Environ Res Public Health. .

Abstract

The etiology of Attention-Deficit/Hyperactivity Disorder (ADHD) is complex and multifactorial. Although the development of ADHD symptoms remains to be elucidated, in recent years, epigenetic processes have emerged as candidate mechanisms. Lead is one of the most dangerous environmental pollutants, and it is suspected to be associated with ADHD. The aim of the present study was to review the epidemiological literature currently available on the relation between lead exposure and the diagnosis of ADHD. The PubMed and EMBASE databases were searched from 1 July 2018 up to 31 July 2018. The authors included observational studies (cohort, case⁻control and cross-sectional studies) published in English carried out on children within the last 5 years, measuring lead exposure and health outcomes related to ADHD. Seventeen studies met the inclusion criteria: 5 of these studies found no association between lead exposure and ADHD whereas the remaining 12 studies showed positive associations, even though not all of them were homogeneous in terms of exposure periods considered or ADHD diagnosis. To conclude, the evidence from the studies allowed us to establish that there is an association between lead and ADHD and that even low levels of lead raise the risk. However, there is still a lack of longitudinal studies about the relationship between lead exposure and the development of ADHD. Given the potential importance for public health, further research that includes the entire potential risk factors for ADHD in children must be encouraged.

Keywords: ADHD; Attention-Deficit/Hyperactivity Disorder; Lead; environmental pollutants; observational studies analysis; systematic review.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
A PRISMA flow diagram for ADHD: Attention-Deficit/Hyperactivity Disorder.
Figure 2
Figure 2
The standardized odds ratios (per 5 µg dL).
See this image and copyright information in PMC

References

    1. Polanczyk G., Willcutt E.G., Salum A.G., Kieling C., Rohde L.A. ADHD prevalence estimates across three decades: An updated systematic review and meta-regression analysis. Int. J. Epidemiol. 2014;43:434–442. doi: 10.1093/ije/dyt261. - DOI - PMC - PubMed
    1. Parekh R. American Psychiatric Association. [(accessed on 26 August 2018)];2017 Available online: https://www.psychiatry.org/patients-families/adhd/what-is-adhd.
    1. American Psychiatric Association Attention Deficit/Hyperactivity Disorder. [(accessed on 9 November 2018)];2013 Available online: https://www.psychiatry.org/File%20Library/Psychiatrists/Practice/DSM/APA....
    1. American Psychiatric Association (APA) Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) APA; Washington, DC, USA: 2000.
    1. Liu A., Xu Y., Yan Q., Tong L. The Prevalence of Attention Deficit/Hyperactivity Disorder among Chinese Children and Adolescents. Sci. Rep. 2018;8:11169. doi: 10.1038/s41598-018-29488-2. - DOI - PMC - PubMed

Publication types