Tobacco-Related Alkaloids as Tracers of ETS in Indoor Air

One objective of our environmental tobacco smoke research program is to assess the impact of ETS on indoor air. Due to the chemical complexity, dynamics, and extreme dilution of ETS in indoor air, and the complexity of the indoor air background, it is impossible to ascertain the concentration level of ETS per se. Attempts are being made to put ETS concentrations into perspective by measuring selected ETS components which can then be used as markers or tracers for ETS as a whole. In this regard, any potential tracer should possess the following attributes (1) it should be unique to or at least highly specific for tobacco smoke (2) it should be in sufficient 

No single ETS component has yet been demonstrated to meet all these criteria successfully. Of all the known constituents of ETS, only the nicotine alkaloids (and selected pyrolysis products) and solanesol (Ogden and Maiolo 1989) appear to offer the required specificity. 

Nicotine is by far the most commonly used indicator of ETS in indoor air. Many authors state erroneously that nicotine is unique to tobacco however, such is not the case. Although present in a surprisingly large number of species other than Nicotiana (Leete 1983), and also detected at trace levels in a variety of common foods (Castro and Monji 1986 Sheen 1988 Davis et al. 1991), the presence of nicotine in indoor air should be uniquely attributable to tobacco smoke. The same should also hold true for the related alkaloids and the more unique pyrolysates (e.g., myosmine and 3 ethenylpyridine). 

Based on the unusual adsorptive and decay characteristics of nicotine, some investigators are turning their attention to 3-ethenylpyridine as a tracer of ETS (Thome et al. 1986 Eatough et al. 1989b Ogden 1991). Second in concentration only to nicotine among the ETS alkaloids, 3-ethenylpyridine more nearly reflects the attributes of an ideal tracer discussed above than do any of the other tobacco alkaloids. 

Due to sparsity of data in the literature, typical indoor air concentrations are difficult to summarize for all of the ETS alkaloids except nicotine. In a recent review of ETS nicotine measurements, Guerin et al. (1992, p. 151) compiled original data from 868 individual sampling locations and report nicotine concentrations lOpg/m in nearly 90% of the cases. Individual measurements can certainly exceed this value however, levels greater than lOOpg/m are rarely encountered. 

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