Document Type : Review Article
Authors
1 Physiology-Pharmacology Research Center, Research Institute of Basic Medical Sciences, Rafsanjan University of Medical Sciences, Rafsanjan, Iran
2 Department of Physiology and Pharmacology, School of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran
Abstract
Background: Heavy metals such as copper, arsenic, and lead are primarily released into the environment through anthropogenic activities. Due to their high toxicity and persistence, these elements pose significant threats to both human health and ecological systems. The main health concern associated with heavy metal exposure is cognitive impairment.
Methods: This review examined studies on the neurotoxic effects of copper, arsenic, and lead, as well as therapeutic strategies aimed at mitigating cognitive decline. Research published between 2000 and 2024 was identified through databases including Google Scholar, PubMed, and Web of Science. Both qualitative and quantitative studies were included, and a dual-review process was employed to enhance the accuracy and reliability of data extraction.
Results: Sources of heavy metal pollution include the combustion of fossil fuels, industrial processes, wastewater discharge, and improper hazardous waste management, all of which contribute to elevated environmental levels of toxic metals. These metals inhibit natural biodegradation processes, leading to increased biological toxicity. While trace levels of certain metals, such as copper, are necessary for physiological functions, chronic or excessive exposure to copper, arsenic, and lead has been linked to cognitive impairments and neurological disorders. Lead exposure is especially associated with severe cognitive deficits in children.
Conclusion: Exposure to elevated levels of copper, arsenic, and lead is strongly associated with neurotoxicity and cognitive decline. Current therapeutic interventions focus primarily on chelating agents and antioxidant therapy to reduce the accumulation and toxic effects of these metals. Continued research is essential to develop more effective strategies for the prevention and treatment of heavy metal-induced cognitive impairment.
Highlights
Jalal Hassanshahi (Google Scholar) (PubMed)
Keywords
Main Subjects
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