Airborne dust collected from Kuwait in 1991–1992 augments peroxidation of cellular membrane lipids and enhances DNA damage

Abstract

This paper reports the results of studies on airborne dust samples collected from the Ahmadi area of Kuwait in 1991, 1992, and 1995. These samples were tested for their ability to enhance peroxidative damage of lipid-rich biological membranes. The damage caused by the dust collected during 1991 and 1992 enhanced both enzymatic and non-enzymatic lipid peroxidation more significantly as compared to the dust collected during 1995. In a separate study, these samples were further tested for their ability to enhance DNA damage. The samples of 1991–92 caused single strand breaks as well as deoxyribose sugar damage. The enhancement in the single strand breaks was 33 to 40%. To find out the mechanism of DNA damage and lipid peroxidation, similar studies were performed in the presence of quenchers of hydroxyl radicals, superoxide anions (O 2), singlet oxygen and hydrogen peroxide (H 2O 2). The O 2 scavenger, superoxide dismutase, and quencher of H 2O 2, catalase, almost abolished the dust-mediated enhancement in DNA damage, suggesting a role of O 2 and H 2O 2 in this process. However, the scavengers of singlet oxygen, β-carotene and hydroxyl radical, ethanol and dimethyl sulfoxide had no effect in suppressing the enhancement of DNA damage and lipid peroxidation. These studies suggest that the airborne dust collected soon after the war was contaminated with certain constituent elements which were effective in enhancing lipid peroxidation and causing DNA damage through the generation of O 2 and H 2O 2.