The effect of different tobacco tar levels on DNA damage in cigarette smoking subjects

Abstract

Objective: To explore the genetic damage caused by different tar levels in the human body. Methods: The subjects were divided into high, medium and low (12 mg, 8 mg, 5 mg) tar groups according to the tar levels. Nonsmoking populations served as a control group. 2 ml of peripheral blood was collected on the 10th day after morning fasting. Oxidative and genetic toxicological damage indicators were analysed with enzyme-linked immunosorbent assay, cytokinesis-block micronucleus assay in human lymphocyte and single cell gel electrophoresis. Results: The distribution of hOGG1 concentration was significantly different within all groups, P < 0.01. The concentrations of cotinine, 8-OHdG and Rap-2b were significantly differences between control and medium tar group, control and high tar group, low and medium tar group and low and high tar group, respectively, P < 0.05. The level of PAH-DNA adducts was not significantly changed in the middle tar group and high tar group, P > 0.05. The level of CRP was significantly changed between control and high tar group, low and high tar group and medium and high tar group, respectively, P < 0.0001. The rate of comet tailing was significantly different between all groups. The rate of micronucleus cells was not significantly different between all groups. Conclusions: The increase of tar content could increase the DNA damage to a certain extent, so the intake of tar content should be monitored.