YF: The influence of antioxidants on cigarette smoke-induced DNA single-strand breaks in mouse organs: a preliminary study with the alkaline single cell gel electrophoresis assay. Toxicol Sci 2000

According to published information, the lung is the only clear target organ for tumors when mice are exposed to cigarette smoke. Liver, skin, and upper digestive tract are target organs when orally or dermally exposed to cigarette smoke condensate, but not kid-ney, brain, or bone marrow. We tested the genotoxicity of cigarette smoke in the known target organ (lung), possible target organs (stomach and liver), and non-target organs (kidney, brain, and bone marrow) of the mouse using the alkaline single-cell gel electrophoresis (SCG, or comet) assay, as modified by us. We also tested the effect of free radical scavengers on the genotoxicity of the smoke. Male ICR mice were exposed to cigarette smoke. DNA single-strand breaks (SSB) were measured by the SCG assay 15, 30, 60, 120, and 240 min after the exposure. Fifteen min after the animals were exposed for 1 min to a 6-fold dilution of smoke, SSB appeared in the lungs, stomach, and liver; the damage in the lung