RESUMO
Objective The genotoxicty and its molecular mechanism of environmental tobacco smoke (ETS) were discussed through the oxidative DNA damage induced by environmental tobacco side_stream smoke(ETSS). Methods DNA adduct 8_hydroxydeoxyguanosine (8_OHdG) was used as a biomarker of oxidative DNA damage. The level of 8_OHdG in DNA exposed to ETSS was detected by HPLC_EC.On the molecular biological level,the biological oxidative ability of ETSS on DNA molecule was studied.Organic and inorganic components in ETSS were analyzed by GC_MS and AAS respectively. Results Particles and VOCs in ETSS could directly induce oxidative DNA damage and form 8_OHdG.It was found that there were 123 and 84 kinds of organic compounds in particles and volatile organic compounds of tobacco smoke side stream,and 7 kinds of inorganic compounds in ETSS.Some components especially quinones and polyphenols in ETS,could produce free radicals in vitro by the auto_oxidation without any biological activity systems,and with the catalytic reaction of metals,the DNA aduct 8_OHdG was produced. Conclusion It was proved that ETS had biological oxidative ability on DNA and expressed direct genotoxicity.8_OHdG was a fine biomarker of effect of oxidative DNA damage.
