(VCCEP) Tier 1 Pilot Submission for BENZENE - Tera

Children may be exposed to benzene from tobacco smoke directly as smokers (mainstream
smoke) or indirectly as non-smokers (ETS). Numerous studies have been conducted to identify
and quantify the individual chemical constituents from tobacco smoke. Researchers have
identified over 4,800 individual constituents, including benzene, in both mainstream smoke and
ETS. Due to physical and chemical differences in burning conditions, benzene has a higher
rate of release per cigarette into sidestream smoke than into mainstream smoke (Wallace and
O’Neill, 1987, Daisey et al., 1994, Fowles et al., 2000, NAP, 1986, Brunnemann et al., 1990a,b,
Darrall et al., 1998).
In order to calculate exposure to benzene, from tobacco smoke exposure, the benzene cigarette
emission rate was determined. Numerous studies have been conducted to evaluate the
chemical emission rates. The following five studies provide the best information:
Daisey et al., 1994. This study tested six commercially available cigarettes that represented
62.5% of the market share in California in 1990 and consisted of filtered, non-filtered, and
mentholated cigarettes. A room-sized environmental chamber was used to measure ETS
emission factors from diluted sidestream smoke, which was emitted into the chamber. This
study concluded that the average emission factor for benzene is 406 µg/cig.
Lance Wallace (Wallace and O’Neill., 1987; Wallace et al. 1989a,b; Wallace, 1996). Several
studies on exposure to benzene and other VOCs from active and passive smoking were
conducted. Wallace determined that the sidestream smoke concentration of benzene (μg/cig) is
5 to 10 times higher than that in mainstream smoke (Wallace and O’Neill, 1987). In another
study, the breath concentration of benzene in smokers and nonsmokers was measured and
reported to be approximately 14 µg/m 3 and 2 µg/m 3 , respectively (Wallace, 1989a,b).
Additionally, benzene concentrations in the homes of smokers and nonsmokers were measured
(Wallace, 1989a,b). The median level of benzene in 300 homes with 1 or more smokers was
3.5 µg/m 3 more than the median level of benzene in a group of 200 homes without smokers. In
the most recent study, Wallace calculated the benzene daily exposure to smokers and
nonsmokers. He determined that smokers are exposed to 2.0 mg benzene/day of which 1.8 mg
benzene/day comes from mainstream smoke and 0.04 mg benzene/day comes from ETS
(Wallace, 1996). He determined that nonsmokers are exposed to 0.2 mg benzene/day of which
0.02 mg benzene/day comes from ETS (Wallace, 1996).
Fowles and Bates, 2000. This study compared the emission rates of benzene in sidestream
smoke and mainstream smoke. It was determined that the exposure of a nonsmoker must take
into account the room dimensions, room ventilation rate, and the amount of time spent with a
smoker. In mainstream smoke, the emission rate of benzene was 46.3 µg/cig. In sidestream
smoke, the emission rate of benzene was 272 µg/cig. These rates are comparable, although
somewhat less than that reported by Daisey et al.
National Academy Press (NAP), 1986. Fresh, undiluted mainstream smoke was measured to
determine the concentrations of benzene. Benzene was measured between 12 and 48 µg in
mainstream smoke and was 5 to 10 times greater in sidestream smoke. Using this information,
it was determined that a nonsmoker living with a smoker has an ETS exposure equivalent to
smoking from 0.36 to 2.79 cig/day. This study also measured the concentration of benzene in
public places to be between 20 and 317 µg/m 3 .
Brunnemann et al., 1990a,b. The emission rate of benzene in several commercially available
cigarettes was measured. In mainstream smoke, benzene ranged from 5.9 µg/cig to 73 µg/cig.
Benzene VCCEP Submission
March 2006
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