Assessment of nicotine exposure and urinary cotinine of tobacco dust exposed workers

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CONTENTS (cont.)

Page Population and sample group 36

Instruments 37

Sample preparation 39

Determination of nicotine concentration in air and residue

on hand by gas chromatography-mass spectrometer (GC-MS) 43 Determination of urinary cotinine concentration by gas

chromatography-mass spectrometer (GC-MS) 47 Reliability of the method 49 Application of the method in the field 50

Statistical analysis 52

CHAPTER IV RESULTS

Determination of nicotine in air and residue on hands 55 Determination of urinary cotinine 61

Field application 65

Statistical analysis of data 81 CHAPTER V DISCUSSION

Reliability of the method 88 Determination of urinary cotinine 89

Field application 90

Analysis of statistical data 92 CHAPTER VI CONCLUSION AND RECOMMENDATIONS

Conclusion 94

Recommendation for further study 96

REFFERENCES 97

APPENDIX

APPENDIX A: Documentary proof of ethical clearance 103 APPENDIX B: Information sheet 104

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CONTENTS (cont.

)

Page APPENDIX C: Questionnaire form 109 APPENDIX D: The analytical results of the samples 112 APPENDIX E: The analytical results of the method 116 APPENDIX F: Quality control chart of the method 118

BIOGRAPHY 119

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LIST OF TABLES

Table Page

2-1 Physical and chemical properties of diphenylamine………….. 19 3-1 Preparation of working standard solution of nicotine…………. 40 3-2 Preparation of working standard solution of cotinine…………. 41 4-1 Show the equation of linear regressions, the correlation

coefficient (R²) and the detection limits of nicotine…………... 57 4-2 The within-day assay for the determination of accuracy

and precision of nicotine……… 57 4-3 The between-day assay for the determination of accuracy

and precision of nicotine……… 58 4-4 (a) Mass recovery of nicotine from PVC filter……….. 59 (b) Mass recovery of nicotine from cotton wool………... 59 4-5 The equation of linear regressions of low level of cotinine,

the correlation coefficient (R²) and the detection limits of

cotinine……….. 63 4-6 The within-day assay for the determination of accuracy

and precision of urinary cotinine………... 64 4-7 The between-day assay for the determination of accuracy

and precision of urinary cotinine………... 64 4-8 The general characteristics of workers exposed to nicotine

dust in dry tobacco leaves preparation area………. 67 4-9 Atmospheric nicotine concentrations of 30 air samples……… 74 4-10 Nicotine concentrations for left and right hands of 30 tobacco

workers……….. 76 4-11 Range and median of urinary cotinine concentrations of

subject classified by tobacco curing and post-curing process… 80

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LIST OF TABLES (cont.)

Table Page

4-12 Range and median of urinary cotinine concentration of comparisons classified by the same time in tobacco curing

and post-curing process……….. 80 4-13 The significant relationship of symptoms occurrence among

workers with job characteristics……… 84 4-14 Number of workers who had symptoms occurrence in

different levels of nicotine exposure………. 84 4-15 The most frequent symptoms occurring of workers………….. 85 4-16 Number of workers who had symptoms occurrence in

different levels of nicotine residue on hands………. 86

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LIST OF FIGURES

Figures Page

2-1 Biosynthesis of nicotine………. 13

2-2 Major pathways of nicotine metabolism……… 16

2-3 Quantitative disposition of nicotine, based on analysis of 24-hour urine collections in habitual cigarette smokers…….… 17

2-4 General schematic of a mass spectrometer………. 21

4-1 Chromatogram of standard nicotine in ethyl acetate………….. 55

4-2 The calibration curve of nicotine……… 56

4-3 Desorption efficiency curves of nicotine……… 60

4-4 (a) Desorption efficiency curves of sample correction for PVC filter……… 60

(b) Desorption efficiency curves of sample correction for cotton wool……….. 60

4-5 Chromatogram of cotinine and diphenylamine (internal standard); a) a blank urine and b) a blank urine spiked with standard cotinine and diphenylamine (internal standard)……… 61

4-6 The calibration curve of cotinine……….. 63

4-7 Tobacco curing area……….. 68

4-8 Tobacco post-curing area……….. 68

4-9 Chromatograms of air composition from workplace obtained by GC-MS. The peaks identified as nicotine (1) and atrazine (2)…. 69 4-10 Chromatograms of personal air sample from an exposed worker obtained by GC-MS using SIM technique. The peaks identified is nicotine (1)……… 70

4-11 Mass spectrums of nicotine from total dust……….. 71

4-12 Mass spectrums of atrazine from total dust………...……… 72

4-13 Mass spectrums of nicotine from air sample………..…. 73

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LIST OF FIGURES (cont.)

Figures Page

4-14 Chromatograms of hand-wipe sample from an exposed worker obtained by GC-MS using SIM technique. The peaks

identified is nicotine (1)………... 74 4-15 Mass spectrums of nicotine from hand-wipe sample……...…... 75 4-16 Chromatograms of urine sample from an exposed workers

obtained by GC-MS using SIM technique. The peaks

identified as nicotine (1), diphenylamine (IS) and cotinine (2)… 77 4-17 Mass spectrums of diphenylamine from urine sample…………. 78 4-18 Mass spectrums of cotinine from urine sample………. 79 4-19 Scatter diagram between nicotine dust concentrations in air

(mg/m³) and urinary cotinine concentrations (µg/ml) of workers in the post tobacco curing process………. 82 4-20 Scatter diagram between nicotine residue on hands (µg/cm²)

and urinary cotinine concentrations (µg/ml) of workers in the

post tobacco curing process……… 82 4-21 Number of workers who had symptoms occurrence in each job

Characteristics………. 83 4-22 Number of workers who had symptoms occurrence in different

levels of nicotine exposure………. 87