Utilization of breath analysis for exposure estimates of benzene associated with active smoking

This study included three different experiments for benzene exposures assoc iated with active smoking. In the first experiment, the mean exhaled breath benzene concentrations measured 1 min after an active smoke ranged from 58 .1 to 81.3 mu g/m(3), depending on the commercial cigarette brand, while th ose measured prior to an active smoke ranged from 15.9 to 19.2 mu g/m(3). T he postexposure breath concentrations were much higher than the mean breath concentrations reported by some previous studies whose exposure conditions and postsampling times were not controlled. Similar to some previous decay studies conducted for different volatile organic compounds in different mi croenvironments, our second experiment showed that there was a rapid fall i n the breath concentration and thereafter the decrease was much slower. One -compartment half-lives ranged from 30.1 to 57.8 min. Two-compartment half- lives ranged from 3.2 to 25.7 min for the first half-life and from 67 to 46 2 min for the second half-life. In the final repeated smoke experiment cond ucted with two specified time intervals, the breath concentrations showed i ncreasing trends for both the pre- and the post exposure concentrations, wi th few exceptions. However, none of the changes mere statistically signific ant at P<0.05. (C) 2000 Academic Press.