Role of oxidative damage in toxicity of particulates

Abstract

Particulates are small particles of solid or liquid suspended in liquid or air. In vitro studies show that particles generate reactive oxygen species, deplete endogenous antioxidants, alter mitochondrial function and produce oxidative damage to lipids and DNA. Surface area, reactivity and chemical composition play important roles in the oxidative potential of particulates. Studies in animal models indicate that particles from combustion processes (generated by combustion of wood or diesel oil), silicate, titanium dioxide and nanoparticles (C₆₀ fullerenes and carbon nanotubes) produce elevated levels of lipid peroxidation products and oxidatively damaged DNA. Biomonitoring studies in humans have shown associations between exposure to air pollution and wood smoke particulates and oxidative damage to DNA, deoxynucleotides and lipids measured in leukocytes, plasma, urine and/or exhaled breath. The results indicate that oxidative stress and elevated levels of oxidatively altered biomolecules are important intermediate endpoints that may be useful markers in hazard characterization of particulates.

Keywords::

• Biomonitoring
• DCFH
• DNA damage
• lipid peroxidation
• nanoparticle
• oxidative stress

Acknowledgements

The authors are supported by grants from the Danish Research Councils.

Declaration of interest: The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper.

This paper was first published online on Early Online on 22 October 2009.