A new analytical procedure has been developed for the simultaneous determination of human hemoglobin adducts from aromatic amines and tobacco-specific nitrosamines. These tobacco-related hemoglobin adducts were determined in nonsmokers, smokers, and users of nasal snuff. Adducts from aminobiphenyl compounds are good biomarkers of exposure to tobacco smoke; they are not elevated in users of nasal snuff. However, a significant contribution of environmental exposure to aromatic amines and/or the corresponding nitroaromatics makes it difficult to evaluate passive exposure to tobacco smoke. The best biomarkers for exposure to tobacco smoke should in theory be adducts arising from tobacco-specific nitrosamines. The common adduct from N'-nitrosonornicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone releases 4-hydroxy-1-(3-pyridyl)-1-butanone from hemoglobin upon mild alkaline hydrolysis and only marginal differences are found in the adduct level in smokers and nonsmokers. The reason for this observation is not yet understood and is currently under investigation. However, the adduct formed by tobacco-specific nitrosamines is well suited for the detection of oral and nasal tobacco use. Only by simultaneous determination of both adducts formed by aromatic amines and tobacco-specific nitrosamines is it possible to differentiate between nonsmokers, smokers, and nasal snuff users.

In non-smokers, haemoglobin adducts from 3- and 4-aminobiphenyl have been reported to arise mainly from exposure to environmental tobacco smoke (ETS). Therefore, the impact of self-reported smoking (n = 27) and exposure of non-smokers to ETS (n = 78) on haemoglobin adducts was studied in pregnant women from Homburg, Germany. In addition to 3- and 4-aminobiphenyl, adducts from seven monocyclic aromatic amines (aniline, o -, m -, and p -toluidine, 2,4-dimethylaniline, 2-ethylaniline and o -anisidine) and the adduct from tobacco-specific nitrosamines (4-hydroxy-1-(3-pyridyl)1-butanone) were determined. Five of 78 self-reported non-smoking women had plasma cotinine levels and urinary cotinine/creatinine ratios indicative of active smoking. In the remaining 73 non-smokers cotinine/creatinine ratios correlated significantly with self reported exposure to ETS. However, none of the haemoglobin adducts increased with increasing exposure to ETS or increasing cotinine/creatinine ratios. Although significantly elevated in smoking compared with non-smoking women, the mean haemoglobin adduct levels formed by tobacco-specific nitrosamines (54 7 8 9 vs 26 7 4 1 fmol g-1, p < 0 001), 3-aminobiphenyl (3 0 0 5 vs 1 4 0 1 pg g-1, p < 0 001), 4-aminobiphenyl (27 9 3 4 vs 10 2 0 7 pg g-1, p < 0 001), o -toluidine (289 25 vs 237 65 pg g-1, p < 0 001), p -toluidine (315 32 vs 197 13 pg g-1; p < 0 001), 2,4-dimethylaniline (25 5 2 9 vs 18 6 1 6 pg g-1, p < 0 05), had considerable overlappings ranges indicating lack of specificity as biomarkers to tobacco smoke exposure. Exposure to other as yet unknown environmental sources appearsto be more significant than previously thought.

A new method for the simultaneous determination of hemoglobin adducts from aromatic amines and tobacco-specific nitrosamines (TSNA) is described. After mild base-catalysed hydrolysis releasing aromatic amines and the TSNA adduct 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB), the extraction, cleanup, and concentration are performed by a one-step procedure using C18 cartridges. Determination in the picograms per gram of hemoglobin range by gas chromatography-mass spectrometry with negative chemical ionization requires a separate derivatization procedure with pentafluoropropionic anhydride and pentafluorobenzoylchloride for aromatic amines and HPB, respectively. The method is shown to be quantitative, reproducible, and applicable to the determination of hemoglobin adducts from monocyclic and bicyclic aromatic amines as well as TSNA in smokers and nonsmokers.

No abstract

No abstract