Ezekiel Izudike Odimgbe1, Micheal Abimbola Oladosu2, Moses Adondua Abah3, Joseph Ezeani4, Alaba Oladapo Gbadebo5 and Chigozirim Steve Amadi6

 1Department of Healthcare Administration and Risk Management, Faculty of Health Sciences, Ohio Dominican University, Ohio-USA

2Department of Chemical Sciences, Faculty of Science, Anchor University, Lagos, Nigeria.

3Department of Biochemistry, Faculty of Pure and Applied Sciences, Federal University of Wukari, Wukari, Taraba State, Nigeria

4Department of Chemical Engineering, Faculty of Engineering, University of Toledo, Toledo, United States.

5Department of Environmental Health Sciences, Faculty of Public Health, University of Ibadan, Ibadan, Nigeria.

6Department of Biochemistry, Faculty of Science, Rivers State University, Port Harcourt, Rivers State, Nigeria.

() Corresponding Author

Received: Apr 19, 2026/ Revised: May 30 2026/Accepted: June 5, 2026 

Highlights

  • Reviews chemical forms, sources, and environmental fate of major heavy metals.
  • Examines toxicological mechanisms including oxidative stress, DNA damage, and organ toxicity.
  • Evaluates anthropogenic sources such as mining, industry, agriculture, and combustion activities.
  • Compares physical, chemical, and biological remediation technologies for contaminated environments.
  • Highlights phytoremediation, microbial bioremediation, and nanotechnology-based remediation approaches.

Abstract

Heavy metal pollution constitutes one of the most pressing environmental and public health challenges of the twenty-first century. Unlike organic pollutants, heavy metals are non-biodegradable, and their persistence in soil, water, and atmospheric compartments poses irreversible ecological risks. This review provides a comprehensive examination of the chemical speciation of key heavy metals, lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), chromium (Cr), and nickel (Ni). It elucidates how their physicochemical forms govern bioavailability, toxicokinetics, and environmental fate. Anthropogenic sources, including mining, industrial effluents, agricultural inputs, and combustion processes, are critically appraised. Toxicological mechanisms involving reactive oxygen species (ROS) generation, enzymatic inhibition, DNA damage, and organ-specific pathologies are discussed with reference to current molecular evidence. Physical, chemical, and biological remediation strategies are comparatively evaluated, with emphasis on phytoremediation, microbial bioremediation, and emerging nanomaterial-assisted approaches. The review underscores the need for integrated, multidisciplinary strategies that combine policy frameworks with green technologies to mitigate heavy metal pollution globally.

Keywords: heavy metals; chemical speciation; environmental pollution; oxidative stress; phytoremediation; bioremediation; toxicity; soil contamination

How to cite this article

Odimgbe, E. I., Oladosu, M. A., Adondua Abah, M., Ezeani, J., Gbadebo, A. O., & Amadi, C. S. (2026). Environmental heavy metal pollution: Chemical forms, sources, toxicological effects, and remediation approaches. Science Archives, 7(2), 124–132. https://doi.org/10.47587/SA.2026.7211

This work is licensed under a Creative Commons Attribution 4.0 International License

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