Open Access

Assessment of nicotine for second hand smoke exposure in some public places in Romania by UPLC-MS

  • Alina Bratan1, 2,
  • Manuela Maria Mincea1,
  • Ioana-Rodica Lupşa2,
  • Marilen-Gabriel Pirtea3 and
  • Vasile Ostafe1, 3Email author
Chemistry Central Journal20148:29

https://doi.org/10.1186/1752-153X-8-29

Received: 8 January 2014

Accepted: 25 April 2014

Published: 3 May 2014

Abstract

Background

Air nicotine monitoring is a well-known procedure for estimation of exposure to second hand smoke. Few research studies were realized in Romania to evaluate environmental tobacco smoke (ETS) exposure of humans in different public places. The levels of airborne nicotine from environmental tobacco smoke and urinary cotinine and nicotine levels of some subjects were analyzed. In order to better implement/enforce the European legislation regarding the interdiction of smoking in the public places the national authorities need a rapid and reliable analytical method to quickly asses the state of the pollution with cigarette smoke of these populated areas.

Results

The nicotine concentration in the air from different types of public buildings was determined. The median concentration of nicotine in the air from 32 pubs where the smoking was allowed was 590 ng · L-1, comparing with the pubs where the smoking was not permitted (22 locations) where the median concentration of nicotine was only 32 ng · L-1. Similarly, the median concentration of nicotine in restaurants where the smoking was allowed (23 locations) was 510 ng · L-1, in comparison with the restaurants where the smoking was prohibited (11 places) where the median value was 19 ng · L-1. The lowest concentrations of nicotine were found in high schools (8 locations, median concentration 7.4 ng · L-1), universities (5 locations, 23 ng · L-1) and hospitals (6 locations, 16 ng · L-1).

Conclusions

The method was validated and gave good linearity, precision, accuracy and limit of detection. The buildings included hospitals, high schools, universities, pubs and restaurants. The presence of air nicotine was recorded in all buildings studied. The highest median levels of air nicotine were found in pubs and restaurants. The presence of air nicotine in indoor public buildings indicates weak implementation of the smoke free law in Romania.

Keywords

Air Nicotine Cotinine UPLC–MS ETS

Background

Environmental tobacco smoke (ETS) is one of the most widespread carcinogenic exposures, being a class A carcinogen, and is considered a preventable occupational health risk. ETS is recognized to be an important risk factor for several chronic diseases such as lung cancer [13], coronary heart disease [47] and asthma [810]. Several epidemiological surveys have documented the link between second hand smoke (SHS) exposure and increased morbidity and mortality [11].

People have become aware of SHS exposure since the studies made during the 9th decade of the previous century [12]. The WHO Framework Convention on Tobacco Control promotes smoke-free environments to protect the health of nonsmokers from SHS [13]. The dissemination of the ETS monitoring studies results is very important especially for young people, because in the age group of 15 to 17 years, there are many persons who have a strong dependence on nicotine [1416].

In Romania, since 2005 smoking in some public places is prohibited by the national law [17], that contains restriction of smoking in different areas such as public places, hospitals, high schools, workplaces, restaurants for nonsmokers, buses and in the vicinity of pregnant women and children [14]. The implementation of the law remained largely ineffective in the first seven years.

Measurement of nicotine is highly sensitive because it is a specific biomarker of tobacco smoke that represents the only possible source of nicotine in the air. Nicotine deposits almost entirely on indoor surfaces in a concentration of about 30 μg · m-3, and persists for weeks to months [18, 19]. Nicotine is rapidly metabolized, the half life time being about 2 h [20]. Cotinine, one of the major nicotine metabolite with a half life time of 20 h is frequently used for assessing tobacco smoke exposure and is typically detectable for several days (up to one week) after the use of tobacco. [20, 21]. Cotinine can be measured in different body fluids or tissues including blood [22] urine, saliva, hair, [23] and teeth [24]. This bio-marker can differentiate the levels of exposure to tobacco smoke and levels of intake. The time needed to acquire increased levels of urinary cotinine is higher than 10 h after heavy ETS in a passive smoker [14].

The methods most used for the ETS monitoring are gas chromatography (GC) with flame ionization detection (FID) or nitrogen specific detectors [25], or GC coupled, with electron impact mass spectrometers (EI-MS) [14, 23, 24, 26] as well as high performance liquid chromatography (HPLC) with MS detectors [27, 28].

The existing surveillance system in Romania has no mechanism for routinely measuring exposure to SHS. There have been few studies or researches to look at exposure to SHS in different environments. In the current study, environmental measurements were used to characterize SHS exposure in key indoor public places in Romania. This paper presents an ultra performance liquid chromatography–mass spectrometric (UPLC–MS) quantitative method for nicotine levels in the indoor air, and for measuring the levels of airborne nicotine in some public houses, as a selective marker of tobacco smoke.

Results

Evaluation of the extraction solvent

Acetonitrile was selected as sampling solvent because it adsorbs/dissolves the highest quantity of nicotine, comparing with the other two solvents used (i.e. methanol and dichloromethane). Moreover, an additional dilution and/or evaporation step could be needed if using dichloromethane.

Method validation

Aliquot samples containing 0.005, 0.02, 0.078, 0.313, 1.250, and 5 μg · mL-1 nicotine in acetonitrile were used for the method validation.

The calibration graph resulted from the analysis of the calibration standard solutions prepared in acetonitrile was linear during the entire range of calibration solutions with a regression curve: y = 2.83 · 107× - 5.51 · 105 and a determination coefficient of 0.9998. The limit of detection (LOD) was 100 ng · mL-1 and the limit of quantification was 300 ng · mL-1 (for details of calculation see Additional file 1).

Precision was studied by collecting directly with the impinger the smoke from one cigarette and repeating the experiment 5 times. The average nicotine quantity found in the smoke collected during 2 minutes of suction at 0.8 L · min-1 was 1320 ± 60 μg per cigarette (RSD 4.6%).

Accuracy was determined by spiking with reference standard solution (1.25 μg · mL-1) 5 blank samples, i.e. collecting air from a well ventilated laboratory. These samples were treated as described in the Sample Preparation procedure. The data obtained were compared with theoretical concentration (i.e. 1.25 μg · mL-1). Under these conditions the accuracy was expressed as percentage recovery: 89% (RSD 8.0%).

Determination of nicotine in air and nicotine and cotinine in urine sample

In order to prove that there is a correlation between the quantities of nicotine inhaled as SHS at the working place, for two volunteers subjects (a non-smoker working in a pub where smoking was allowed and a non-smoker janitor from a hospital) the urine samples were also analyzed. Both of them have been working in their institutions for more than 6 months. The nicotine and cotinine levels present in their urine were considerably higher than the levels found in the urine of a technician (also non-smoker) working in a ventilated laboratory.

MS/MS optimized conditions for the Xevo TQD MS instrument are presented in Table 1. Figure 1 presents MS/MS spectra of nicotine (a panel) and cotinine (b panel). These spectra were used to select appropriate transitions for the quantification of these two analytes.
Table 1

Mass spectrometer parameters for nicotine and cotinine detection

Analyte

MRM transitions*

Cone voltage (V)

Collision potential (V)

LOD (ng · mL-1)

LOQ (ng · mL-1)

Nicotine

163 > 130 (117)

32

22

1

2.5

Cotinine

177 > 98 (80)

42

30

1

2.5

* m/z of precursor ion > m/z of the fragment used for quantification (m/z of the fragment used for confirmation).

Figure 1

Fragmentation mass spectra of nicotine (upper panel) and cotinine (lower panel) in the conditions mentioned in Table 1 .

As it can see from Table 2, there is a significant connection between the level of nicotine in the breathed air and the urine level of nicotine and cotinine, proving that the secondary smoke can be almost as dangerous as the primary/direct smoking.
Table 2

Correlation between SHS expressed as nicotine in inhaled air for 8 h and nicotine and cotinine level in urine

 

Barman in a Pub where smoking was allowed

Janitor in a hospital

Laboratory technician

Nicotine in air (ng · L-1)

778

12

<LOQ

Cotinine in urine (ng · mL-1)

2241

34

<LOQ

Nicotine in urine (ng · mL-1)

373

5.7

<LOQ

As an example, Figure 2 shows two MRM chromatograms (transition 163 > 130) for nicotine analysis in air in a non-smoking pub (upper panel) and a smoking pub (lower panel). The difference between the nicotine content in those two environments, given by the scale in the top right corner, is of two orders of magnitude.
Figure 2

Nicotine MRM (transition 163 > 130) chromatogram of the air sampled from a non-smoking pub (upper panel) and a smoking pub (lower panel). The conditions are presented in Table 1.

Air nicotine concentrations (ng · L-1) in different types of buildings are presented in Figure 3. Buildings were monitored randomly at different hours during open program, in order to obtain unbiased samples. From the same building the sampling experiment was performed three times, in different days, at different hours and the results (presented in Table 3) were averaged. For this study high schools, universities, hospitals, pubs and restaurants were considered. For high schools and universities the samples were collected from the corridors situated at the main entrance. In the hospitals, the samples were collected from the main waiting rooms, in some cases this room being common with cafeteria. Regarding the eating-drinking places two categories of pubs and restaurants were studied: smoking and nonsmoking spaces.
Figure 3

Concentration of nicotine (ng · L -1 ) in different types of buildings: 1 = high schools (corridor), 2 = universities (corridor), 3 = hospitals (waiting rooms), 4 = Pubs (with smoking allowed), 5 = pubs (with smoking prohibited), 6 = Restaurants (with smoking allowed), 7 = Restaurants (with smoking prohibited). The horizontal lines represent the median concentration.

Table 3

The levels of air nicotine in different building categories

Building category

No. of buildings in the category

Median concentration* (ng · L-1)

Low (ng · L-1)

High (ng · L-1)

High schools (corridor)

8

7.4

3

12

Universities (corridor)

5

23.0

17

35

Hospitals (waiting room)

6

15.7

8

27

Pubs (smoking)

32

591.1

144

988

Pubs (nonsmoking)

22

32.1

8

85

Restaurants (smoking)

23

509.3

169

897

Restaurants (nonsmoking)

11

19.5

4

65

*mean of three days.

As expected, the highest median levels of air nicotine were found in pubs, followed by restaurants, where the smoking was permitted (Table 3 and Figure 3). Measurable levels of air nicotine were found on corridors of high schools and of waiting rooms of hospitals.

Discussion

UPLC-MS/MS is an appealing alternative to the GC assays due to the fact that sample preparation may be more straightforward than in GC–MS techniques [29] and because the UPLC separation method is more rapid than the GC method [14]. The UPLC–MS method presented for determination of nicotine concentrations in air is simple and rapid. The method validation gave the following values: 4.6% RSD precision and 8.0% RSD for accuracy. These results are comparable with the published LC methods for quantification of nicotine (and cotinine) although these analytical procedures were used for quantification of these compounds in serum [27] or urine [28].

This study shows that tobacco smoke is present in all public places examined from Timisoara. The study also demonstrated that in buildings where smoking is not allowed, levels of nicotine in the air are lower than in places where smoking is permitted but they are not zero. This implies that policies of having both smoking and non-smoking places are not entirely useful.

The nicotine concentrations found in pubs and restaurants where the smoking was permitted are very high. For someone who spent his time in such a place for 4–5 hours is equivalent to living with a smoker for one month. Similar results were mentioned by Nebot [30] and Hammond [31]. Comparing the results published by other studies, the concentrations of nicotine from Romanian pubs and restaurants where the smoking is allowed were higher than the majority of other public places [30, 3235], indication that either the law should not permit the smoking in any public place or these locations should have better ventilation systems.

Conclusions

According with the published data of US Occupational Safety and Health Administration [36] a concentration of nicotine in the breathing air higher than 6.8 μg · L-1 is considered to be “significant harm” for the humans exposed daily for more than 40 years. In this context, one may conclude that at least for employees and regular customers of Romanian pubs and restaurants where smoking is still allowed the risk to develop a lung cancer is one in 1000. In fact, all the analyzed pubs and restaurants where the smoking was allowed have higher concentration of nicotine in the air than the threshold level mentioned above. The World Health Organization stated that there is no proof for a not dangerous ETS exposure level [37] and our research confirmed that in many Romanian public buildings there are measurable levels of ETS exposure. The outcomes of this report indicate that properly implemented smoke-free strategies are necessary to reduce ETS exposure in indoor places.

Although the Romanian law prohibits smoking in all public buildings the enforcement of this law is very poor. This study may be considered as a scientific evidence for what the general public agree and feel, that new means should be envisaged by the authorities in order to really stop the smoking in the public places. Beside higher fees or other types of penalties applied to smokers and to the owners of the public places where the nicotine levels are found to be increased, educational programs regarding the health risks associated with tobacco smoke and benefits of smoking cessation should also be considered.

Methods

Materials

(S)-Nicotine ((S)-3-(1-Methyl-2-pyrrolidinyl)pyridine, Fluka N5511, 1 mg · mL-1 in methanol) and (S)-cotinine ((S)-1-Methyl-5-(3-pyridyl)-2-pyrrolidinone, Fluka C0430, 1 mg · mL-1 in methanol) were purchased from Sigma-Aldrich. All other solvents and reagents were of chromatography quality, purchased also from Sigma – Aldrich: ammonium formate (12466 Fluka), formic acid (06440 Fluka), dichloromethane (CHROMASOLV, 439223 Sigma), methanol (LC-MS CHROMASOLV, 34860 Sigma), acetonitrile (LC-MS CRHOMASOLV, Fluka 14261). HPLC grade water was prepared by SG Ultra Clear 2001-B Water Deionization System (Cole-Parmer) and additionally filtered through syringe filters PTFE 0,22 μm (Teknokroma, Barcelona, Spain) immediately before use.

Working solutions 0.1 mg · mL-1 of each standard were made in 0.1% ammonium formate in 10% acetonitrile (buffered at pH 5.5) and from this, the calibration standards dilutions between 5 μg · mL-1 and 0.005 μg · mL-1 were freshly prepared before each analytical series.

Sampling

For the current study, a survey was conducted across the city of Timisoara, sampling the air from different public places. The types of buildings considered for this study included hospitals, high schools, pubs, and restaurants. Sampling locations were selected to represent the areas where people frequently work or occupy. Second hand smoke was estimated by sampling of vapor-phase nicotine using an air pump (model HB3344-02 Tuff Personal Air Sampling, produced by Casella Cell, Badford, UK) coupled with an impinger (Pyrex glass Midget Impinger, from SKC Ltd, Dorset, UK) filled with 15 mL solvent (usually acetonitrile) for extraction/desolvation of nicotine from pumped air. The pump was set up to pump at a flow of 800 mL/min, for 15 minutes. Each building selected for this survey was monitored randomly at different hours during open program. The samples were collected in three different days and the results were presented as mean of the individual results.

For quality assurance and control purposes, a fixed sampling procedure was used to collect one blank sample for each of the 8–12 samples. For blanks, air samples were collected from a ventilated laboratory and they were handled and analyzed in the same way as the rest of the samples. The blanks were used to determine the method limit of detection and to calculate blank-corrected nicotine concentrations [38].

Sample preparation

After passing 12 L air through pump (at a 0.8 L/min flow), the nicotine was extracted into acetonitrile (methanol and dichloromethane were also tested). The solvent was evaporated under gentle stream of nitrogen. The residue was re-dissolved in 100 μL of mobile phase used for the equilibration of the analytic column. The samples were filtered on 0.2 μm PTFE filters and afterwards 5 μL of sample was injected into chromatographic system. By this procedure the initial samples were concentrated 150 times and in these condition the LOQ is 2.5 ng/L air collected.

The determination of nicotine and cotinine in urine samples, including collection, sample preparation, chromatographic separation and quantification are described elsewhere [39].

Apparatus

UPLC–MS analyses were performed to determine the nicotine in air samples and urinary nicotine and cotinine. The chromatographical analysis was carried out on a Waters Acquity UPLC-MS system (Binary Solvent Manager, Xevo TQD equipped with an electrospray ionization interface) with a UPLC BEH Phenyl 1.7 μm column (2.1 × 100 mm) using a gradient elution procedure. Mobile phase A consisted in 0.1% ammonium formate in acetonitrile and mobile phase B was 0.1% ammonium formate in 10% acetonitrile. The gradient profile was: 0 – 0.5 min, 100% B; 0.5 – 1 min, 95% B; 1 – 1.5 min, 0% B; 1.5 – 1.9, 0% B; 1.9 – 2 min, 100% B. The column temperature was set at 30°C. The analyses were run at a flow rate of 0.4 mL/min, and the sample volume injected was 5 μL. The ESI parameters for Xevo TQD MS detector were fixed as follows: capillary voltage at 3 kV, source temperature at 120°C, desolvation temperature at 450°C, and desolvation gas at 800 L/h. Nitrogen was used as the desolvation gas, and argon was employed as the collision gas. The detailed MS/MS detection parameters for each analyte are presented in Table 1 and were optimized by infusion of a 1 μg mL-1 standard solution of each analyte into the detector at a flow rate of 10 μL · min-1.

Analyses were carried out in multiple reaction monitoring mode, using two specific transitions for each analyte and the detector was fixed at maximum Extended Dynamic Range with peak mass widths of 2 and 1.5 amu for the first and third quadrupoles, respectively. The dwell time for all transitions was 0.01 seconds.

Ethics

The study was approved by the Ethical Structures of the institutions to whom the authors are affiliated.

Declarations

Acknowledgements

This work was supported by the project 464 RoS-NET financed by the EU Instrument for Pre-Accession (IPA) funds, under the framework of the Romania-Republic of Serbia IPA Cross-border Cooperation Programme.

Authors’ Affiliations

(1)
West University of Timisoara, Timisoara, Faculty of Chemistry – Biology –Geography, Advanced Research Environmental Laboratories
(2)
National Institute of Public Health, Regional Center of Public Health, Timisoara
(3)
Multidisciplinary Research Platform “Nicholas Georges - Roegen”, West University of Timisoara

References

  1. Hirayama T: Non-smoking wives of heavy smokers have a higher risk of lung cancer: a study from Japan. Br Med J. 1981, 282: 183-185. 10.1136/bmj.282.6259.183.View ArticleGoogle Scholar
  2. Trichopoulos D, Kalandid A, Sparros L: Lung cancer and passive smoking: conclusion of Greek study. Lancet. 1983, 17: 677-678.View ArticleGoogle Scholar
  3. Brennan P, Buffler PA, Reynolds P, Wu AH, Wichmann HE, Agudo A, Pershagen G, Jockel KH, Benhamou S, Greenberg RS, Merletti F, Winck C, Fontham ET, Kreuzer M, Darby SC, Forastiere F, Simonato L, Boffetta P: Second hand smoke exposure in adulthood and risk of lung cancer among never smokers: a pooled analysis of two large studies. Int J Cancer. 2004, 109: 125-131. 10.1002/ijc.11682.View ArticleGoogle Scholar
  4. Steenland K: Passive smoking and the risk of heart disease. JAMA. 1992, 267: 94-99. 10.1001/jama.1992.03480010102033.View ArticleGoogle Scholar
  5. Otsuka R, Watanabe H, Hirata K, Tokai K, Muro T, Yoshiyama M, Takeuchi K, Yoshikawa J: Acute effects of passive smoking on the coronary circulation in healthy young adults. JAMA. 2001, 286: 436-441. 10.1001/jama.286.4.436.View ArticleGoogle Scholar
  6. He J, Vupputuri S, Allen K, Prerost MR, Hughes J, Whelton PK: Passive smoking and the risk of coronary heart disease, a meta-analysis of epidemiological studies. N Engl J Med. 1999, 10: 2384-2391.Google Scholar
  7. Pitsavos C, Panagiotakos DB, Chrysohoou C, Skoumas J, Tzioumis K, Stefanadis C, Toutouzas P: Association between exposure to environmental tobacco smoke and the development of acute coronary syndromes. The CARDIO 2000 case control study. Tob Control. 2002, 11: 220-225. 10.1136/tc.11.3.220.View ArticleGoogle Scholar
  8. Burchfield CM, Higgins MW, Keller JB, Howatt WF, Butler WJ, Higgins ITT: Passive smoking in childhood: respiratory conditions and pulmonary function in Tecumseh, Michigan. Am Rev Respir Dis. 1996, 133: 966-973.Google Scholar
  9. Evans D, Levison MJ, Feldman CH, Clark NM, Wasilewski Y, Levin B, Mellines RB: The impact of passive smoking on emergency room visits of urban children with asthma. Am Rev Respir Dis. 1987, 135: 567-572.Google Scholar
  10. Das SK: Harmful effects of cigarette smoking. Mol Cell Biochem. 2003, 253: 159-165. 10.1023/A:1026024829294.View ArticleGoogle Scholar
  11. Kraev TA, Adamkiewicz G, Hammond SK, Spengler JD: Indoor concentrations of nicotine in low-income, multi-unit housing: associations with smoking behaviors and housing characteristics. Tob Control. 2009, 18: 438-444. 10.1136/tc.2009.029728.View ArticleGoogle Scholar
  12. Tuomi T, Johnson T, Reijula K: Analysis of nicotine, 3-hydroxycotinine, cotinine, and caffeine in urine of passive smokers by HPLC tandem mass spectrometry. Clin Chem. 1999, 45: 2164-2172.Google Scholar
  13. World Health Organization (WHO): Framework Convention on Tobacco Control (FMCTC) Article 8. 2004. 2012Google Scholar
  14. Culea M, Cozar O, Nicoara S, Podea R: Exposure assessment of nicotine and cotinine by GC–MS. Indoor Built Environ. 2005, 14: 293-299. 10.1177/1420326X05054296.View ArticleGoogle Scholar
  15. Hruba D, Zachovalova L, Fiala J, Kyasova M: Evaluation of the level of nicotine dependence among adolescent smokers. Cent Eur J Public Health. 2003, 11 (3): 163-168.Google Scholar
  16. Eisner MD: Environmental tobacco smoke exposure and pulmonary function among adults in NHANES III: impact on the general population and adults with current asthma. Environ Health Perspect. 2002, 110 (8): 765-770. 10.1289/ehp.02110765.View ArticleGoogle Scholar
  17. Romanian Law no. 332/2005 regarding the ratification of the WHO Framework Convention on Tobacco Control. published in Official Monitor no. 1088 of 2 December 2005Google Scholar
  18. Singer BC, Hodgson AT, Nazaroff WW: Gas-phase organics in environmental tobacco smoke: exposure-relevant emission factors and indirect exposure from habitual smoking. Atmos Environ. 2003, 37: 5551-5561. 10.1016/j.atmosenv.2003.07.015.View ArticleGoogle Scholar
  19. Singer BC, Revzan KL, Hotchi T, Hodgson AT, Brown NJ: Sorption of organic gases in a furnished room. Atmos Environ. 2004, 38: 2483-2494. 10.1016/j.atmosenv.2004.02.003.View ArticleGoogle Scholar
  20. Florek E, Piekoszewski W, Wrzosek J: Relationship between the level and time of exposure to tobacco smoke and urine nicotine and cotinine concentration. Pol J Pharmacol. 2003, 55 (1): 97-102.Google Scholar
  21. Chen R, Tavendale R, Tunstall-Pedoe H: Measurement of passive smoking in adults: self-reported questionnaire or serum cotinine?. J Canc Epidemiol Prev. 2002, 7 (2): 85-95. 10.1080/147666502321082746.View ArticleGoogle Scholar
  22. de Leon J, Diaz FJ, Rogers T, Browne D, Dinsmore L, Ghosheh OH, Dwoskin LP, Crooks PA: Total cotinine in plasma: a stable bio-marker for exposure to tobacco smoke. J Clin Psychopharmacol. 2002, 22 (5): 496-501. 10.1097/00004714-200210000-00009.View ArticleGoogle Scholar
  23. Torano JS, van Kan HJ: Simultaneous determination of the tobacco smoke uptake parameters nicotine, cotinine and thiocyanate in urine, saliva and hair, using gas chromatography- mass spectrometry for characterisation of smoking status of recently exposed subjects. Analyst. 2003, 128 (7): 838-843. 10.1039/b304051h.View ArticleGoogle Scholar
  24. Pasqual JA, Diaz D, Segura J, Garcia-Algar O, Valt O, Zuccaro P, Pacifici R, Pichini S: A simple and reliable method for the determination of nicotine and cotinine in teeth by gas chromatography/mass spectrometry. Rapid Commun Mass Spectrom. 2003, 17: 2853-2855. 10.1002/rcm.1279.View ArticleGoogle Scholar
  25. Koszowski B, Goniewicz ML, Czogala J, Zymelka A, Sobczak A: Simultaneous determination of nicotine and 3-vinylpyridine in single cigarette tobacco smoke and in indoor air using direct extraction to solid phase. Int J Environ Anal Chem. 2009, 89 (2): 105-117. 10.1080/03067310802549946.View ArticleGoogle Scholar
  26. Heinrich-Ramm R, Wegner R, Garde AH, Baur X: Cotinine excretion (tobacco smoke bio-marker) of smokers and non-smokers: comparison of GC/MS and RIA results. Int J Hyg Environ Health. 2002, 205 (6): 493-499. 10.1078/1438-4639-00173.View ArticleGoogle Scholar
  27. Bernert JT, Mayman E, Turner WE, Pirkle JL, Sosnoff CS, Akins JR, Waldrep MK, Ann Q, Covey TR, Whitfield WE, Gunter EW, Miller BB, Patterson DG, Needham LL, Hannon WH, Sampson EJ: Development and validation of sensitive method for determination of serum cotinine in smokers and nonsmokers by liquid chromatography/atmospheric pressure ionization tandem mass spectrometry. Clin Chem. 1997, 43 (12): 2281-2291.Google Scholar
  28. Bratan A, Mincea M, Lupşa I, Ostafe V: An UPLC method for the assessment of nicotine and cotinine in urine. AWUT-SC. 2009, 18 (1): 93-102.Google Scholar
  29. Hoofnagle AN, Laha TJ, Rainey PM, Sadrzadeh SMH: Specific detection of anabasine, nicotine, and nicotine metabolites in urine by liquid chromatography–tandem mass spectrometry. Am J Clin Pathol. 2006, 126: 880-887. 10.1309/LQ8U3UL956ET324X.View ArticleGoogle Scholar
  30. Nebot M, López MJ, Gorini G, Neuberger M, Axelsson S, Pilali M, Fonseca C, Abdennbi K, Hackshaw A, Moshammer H, Laurent AM, Salles J, Georgouli M, Fondelli MC, Serrahima E, Centrich F, Hammond SK: Environmental tobacco smoke exposure in public places of European cities. Tob Control. 2005, 14: 60-63. 10.1136/tc.2004.008581.View ArticleGoogle Scholar
  31. Hammond K: Evaluating exposure to environmental tobacco smoke. Sampling and analysis of airborne pollutants. Edited by: Winegar E, Keith L. 1993, Boca Raton, Fl: Lewis Publishers, 319-338.Google Scholar
  32. Mulcahy M, Evans DS, Hammond SK, Repace JL, Byrne M: Secondhand smoke exposure and risk following the Irish smoking ban: an assessment of salivary cotinine concentrations in hotel workers and air nicotine levels in bars. Tob Control. 2005, 14: 384-388. 10.1136/tc.2005.011635.View ArticleGoogle Scholar
  33. Gasparrini A, Gorini G, Marcolina D, Albertini M, Fondelli MC, Tamang E, Nebot M: Second-hand smoke exposure in Florence and Belluno before and after the Italian smoke-free legislation. Epidemiol Prev. 2006, 30 (6): 348-351.Google Scholar
  34. Erazo M, Iglesias V, Droppelmann A, Acuña M, Peruga A, Breysse PN, Navas-Acien A: Secondhand tobacco smoke in bars and restaurants in Santiago, Chile: evaluation of partial smoking ban legislation in public places. Tob Control. 2010, 19 (6): 469-474. 10.1136/tc.2009.035402.View ArticleGoogle Scholar
  35. Blanco-Marquizo A, Goja B, Peruga A, Jones MR, Yuan J, Samet JM, Breysse PN, Navas-Acien A: Reduction of secondhand tobacco smoke in public places following national smoke-free legislation in Uruguay. Tob Control. 2010, 19 (3): 231-234. 10.1136/tc.2009.034769.View ArticleGoogle Scholar
  36. Hammond SK, Sorensens G, Youngstrom R, Ockene JK: Occupational exposure to environmental tobacco smoke. JAMA. 1995, 274: 956-960. 10.1001/jama.1995.03530120048040.View ArticleGoogle Scholar
  37. World Health Organization: Air quality guidelines, European Series, Volume 91. 2000, Copenhagen: WHO, Regional Office for Europe, 2Google Scholar
  38. Kaur J, Prasad VM: Air nicotine monitoring for second hand smoke exposure in public places in India. Indian J Community Med. 2011, 36 (2): 98-103. 10.4103/0970-0218.84126.View ArticleGoogle Scholar
  39. Bratan A, Mincea M, Lupsa IR, Pirtea MG, Ostafe V: Quantification of nicotine and cotinine in teenager’s urine. Stud UBB Chemia. 2014, 1: 47-61. LIXGoogle Scholar

Copyright

© Bratan et al.; licensee Chemistry Central Ltd. 2014

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.