Estimation of urinary cotinine cut-off points distinguishing non-smokers, passive and active smokers.

An objective assessment of exposure to tobacco smoke may be accomplished by means of examining particular biomarkers in body fluids. The most common biomarker of tobacco smoke exposure is urinary, or serum, cotinine. In order to distinguish non-smokers from passive smokers and passive smokers from active smokers, it is necessary to estimate cotinine cut-off points. The objective of this article was to apply statistical distribution of urinary cotinine concentration to estimate cut-off points distinguishing the three above-mentioned groups. The examined group consisted of 327 volunteers (187 women and 140 men) who were ethnically homogenous inhabitants of the same urban agglomeration (Sosnowiec, Poland). The values which enabled differentiation of the examined population into groups and subgroups were as follows: 50 microg l(-1) (differentiation of non-smokers from passive smokers), 170 microg l(-1) (to divide the group of passive smokers into two subgroups: minimally and highly exposed to environmental tobacco smoke), 550 microg l(-1) (differentiation of passive smokers from active smokers), and 2100 microg l(-1) (to divide group of active smokers into two subgroups: minimally and highly exposed to tobacco smoke). The results suggest that statistical distribution of urinary cotinine concentration is useful for estimating urinary cotinine cut-off points and for assessing the smoking status of persons exposed to tobacco smoke.

[Determination of urinary cotinine and 1-hydroxypyrene and blood carboxyhemoglobine as the biomarkers of tobacco smoke exposure]. / Ocena przydatnosci 1-hydroksypirenu, karboksyhemoglobiny i kotyniny jako biomarkerów narazenia na dym tytoniowy.

The following biomarkers: cotinine, 1-hydroxypyrene (1-OHP) and carboxyhemoglobin (HbCO) were used for the estimation of the tobacco smoke exposure. In our study urine and blood sampled from 98 volunteers were subjected to assessment of the biomarkers concentrations under investigation. According to the self-reports of the volunteers, all of the volunteers were divided into three groups: non-smokers, passive and active smokers. The mean values of the biomarker concentrations were calculated for these groups. In order to verify the tobacco smoke exposure specified by volunteers, we tested the real urinary cotinine amount. Based on obtained values of this biomarker, the another volunteer's partition into the groups of nonsmokers, passive and active smokers were done. The new mean values for all of these groups were calculated. The mean values obtained for both group partitions differed. The latter partition gave opportunity to use 1-OHP for the estimation of the tobacco smoke exposure not only for the active smokers but also for the passive smokers. When HbCO was taken into consideration as the biomarker, the estimation of the tobacco smoke exposure of the passive smokers was not significant different, as compared with the group of nonsmokers. The analysis of the correlation between the concentrations of 1-OHP and cotinine gave opportunity for the estimation to tobacco smoke exposure of the passive and active smokers. The estimation of the correlation, between the HbCO and cotinine concentrations was restricted for this purpose.

[Biomarkers of tobacco smoke]. / Biomarkery narazenia na dym tytoniowy.

In order to estimate the exposure of passive and active smokers to tobacco smoke one can use the questionnaire method or laboratory examination of chemical compounds being widely accepted exposure biomarkers. Substances that make such biomarkers include some of the tobacco smoke components and its metabolites formed in the body. The study discusses two groups of biomarkers. First, includes substances that serve as exposure markers of carcinogenous properties (metabolites of polycyclic aromatic hydrocarbons, N-nitrosamines, trans,transmuconic acid, S-phenylmercapturic acid). Second group includes substances which role is limited to the evaluation of exposure to tobacco smoke (nicotine, cotinine, anatabine, anabasine, trans-3'-hydroxycotinine, thiocyanate, carboxyhemoglobin, carbon monoxide). Sensitivity and specificity of biomakers used were evaluated, their concentration ranges in physiological fluids in non-smokers, passive-, and active smokers. The simplicity of the examination method was evaluated. Articles published during last two decades indicate that the substance that have all features that make it the most appropriate biomarker is cotinine. It can be assessed in plasma and in urine of smokers and persons exposed to environmental tobacco smoke.

The influence of smoking on plasma homocysteine and cysteine levels in passive and active smokers.

Total plasma homocysteine (tHcy) and cysteine (tCys) levels are associated with cardiovascular diseases. One of the determinants that influence their levels is cigarette smoking. The aim of this study was to determine the relationship between plasma levels of both amino acids and urinary cotinine concentration as a reliable biomarker of tobacco smoke exposure. One hundred and seventeen volunteers (61 women and 56 men) aged 19-60 years (mean 40.3 +/- 11.0) were included in the study. The study subjects were qualified into non-smokers, passive smokers and active smokers based upon the urinary cotinine concentration. In each particular group, plasma tHcy and tCys levels were measured and evaluated in the whole population and separately in women and men. Statistically insignificant differences in plasma tHcy and tCys levels in the whole group of passive smokers in comparison with non-smokers were observed (11.47 vs. 10.94 micromol/l, p=0.414, and 253.0 vs. 266.9 micromol/l, p=0.163, respectively). However, statistically significant differences in plasma tHcy levels (13.29 vs. 10.94 micromol/l, p=0.011) and in plasma tCys levels (218.2 vs. 266.9 micromol/l, p<0.001) were found in the whole group of active smokers compared with non-smokers. The Pearson's coefficient (r) for the correlation between plasma tHcy level and urinary cotinine concentration was r=0.630 (p<0.001) in the whole group of active smokers and r=0.480 (p=0.003) in the whole group of passive smokers. The correlation between plasma tCys level and urinary cotinine concentration in both study groups was insignificant. Similar results were obtained when calculated separately for men and women. The results suggest that cigarette smoking is a strong determinant of plasma tHcy level, but it is not a determinant of plasma tCys level.

[Evaluation of the tobacco smoke exposure among students living in students' dormitories]. / Ocena narazenia studentów, mieszkanców domu studenckiego, na dym tytoniowy.

Passive smoking results from involuntary smoke inhalation in the environment where tobacco and other tobacco products are smoked. This is a common situation in numerous public objects, as restaurants, offices, dormitories and students' clubs. Non-smokers are exposed to very high concentrations of tobacco smoke in these places. Environmental exposure to tobacco smoke of the inhabitants of the Pharmacy School dormitory in Sosnowiec was studied. The evaluation was based on urine cotinine concentration measured with the HPLC method. Additionally, a Fagerström test was conducted among declared smokers in order to evaluate the degree of their pharmacologic addiction to nicotine. The obtained results indicate that non-smoking dormitory inhabitants are strongly exposed to environmental tobacco smoke, but active smokers did not presented with pharmacological addiction to nicotine.