[Active oxygen species and asbestos toxicity]

Abstract

It has been demonstrated that active oxygen species is involved in inflammation, immunologic disorders, cancer, etc. Along this line, biological effects of asbestos have been investigated. The results of these studies can be classified into two groups. The first is based on researches on hydroxy radical, the most active oxygen species which originates through the catalytic reaction of asbestos iron. It has been confirmed that cigarette smoke enhances hydroxy radical induction with asbestos exposure. This combined exposure causes greater DNA damages than exposure to them independently. The second is based on researches on release of active oxygen species due to interaction between asbestos and phagocytic cells. In addition to either alveolar or peritoneal macrophages and polymorphonuclear leukocytes, lung fibroblast and endarterial cells have been confirmed to release active oxygen species after exposure to asbestos. However, this has not been confirmed with mesothelial cells. These evidences associated with asbestos exposure and generation of active oxygen species are available for checking the safety of many kinds of synthetic mineral fibers which are recently replacing asbestos.