Biomarker Comparisons Between Adult Menthol and Non-Menthol Cigarette Smokers

Transcription

1 Biomarker Comparisons Between Adult and Non- Cigarette Smokers Mohamadi A. Sarkar, M.Pharm., Ph.D., Senior Principal Scientist Altria Client Services 1 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

2 Outline Background Total Exposure Study Design and Conduct Comparisons between adult menthol and non-menthol smokers Demographics Biomarkers of Exposure Metabolite Ratios Biomarkers of Potential Harm Nicotine Dependence Scores Summary & Conclusions 2 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

3 Background Most of the studies assessing cigarette smoke exposure between adult menthol and non-menthol smokers report no differences (Ahijevych et al. 1996; Rosenblatt et al. 1998; Patterson et al. 2003; Heck 2009; Wang et al. 2009; Muscat et al. 2009; Ritchie et al. 1997) Research on possible effects of menthol on nicotine and NNK a metabolism has yielded inconsistent findings (Muscat et al. 2009; Ritchie et al. 1997; Berg et al. 2009; Ahijevych et al. 2002; Benowitz et al. 2004) It has been hypothesized that the metabolic inhibition may impact disease risk and/or smoking behavior a 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone 3 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

4 PM USA Study Total Exposure Study TES The TES was a stratified, multi-center, cross-sectional study that had 3585 evaluable adult smokers and 1077 evaluable nonsmokers from 31 states (39 investigative sites) across the U.S. States with sites 4 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

5 TES Study Conduct Participants were generally healthy adult males and females, 21 years of age and older The study was Institutional Review Board approved and conducted in accordance with Good Clinical Practice Smoking status was defined as consumption of a minimum of one commercially available cigarette per day over the last 12-months Blood and 24-hour urine samples as well as other measurements were collected from the participants Adult smokers were asked to return all cigarette butts smoked over the 24-hour period 5 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

6 Objectives of the TES Primary objectives: To estimate the exposure of U.S. adult cigarette smokers to selected cigarette smoke constituents To investigate the relationship between cigarette smoke exposure of U.S. adult smokers and tar delivery a Secondary objectives: To compare selected biomarkers of U.S. adult smokers to adult non-smokers To evaluate smoking behaviour as it relates to cigarette smoke exposure To investigate the relationship between selected biomarkers of potential harm and cigarette smoke exposure a Measured by the Cambridge filter method 6 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

7 Biomarkers of Exposure Biomarker Sample matrix Representative smoke constituent Gas Phase Carboxyhemoglobin Blood Carbon monoxide 3-hydroxypropylmercapturic acid (3- HPMA) 24-hour urine Acrolein Monohydroxybutenylmercapturic acid (MHBMA) and dihydroxybutylmercapturic acid (DHBMA) Particulate phase 24-hour urine 1,3-Butadiene 4-Aminobiphenyl adducts Blood Aminobiphenyl Nicotine, cotinine, trans-3-24-hour urine Nicotine hydroxycotinine and their glucuronide conjugates A Total NNAL B 24-hour urine NNK C Total 1-hydroxypyrene 24-hour urine Pyrene A The molar sum of nicotine and its five major metabolites were expressed as nicotine equivalents (NE) B 4- (methylnitrosamino)-1-(3-pyridyl)-1-butanol; C 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone 7 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

8 Biomarkers of Potential Harm a Biomarker of Potential Harm Matrix Oxidative Stress 8-epi-prostaglandin F2α (ng/24h) Urine Inflammation White Blood Cells (x1000/ul) Blood hs C-Reactive Protein (mg/l) Blood Fibrinogen (mg/dl) Blood Platelet Activation 11-dehydrothromboxane B 2 (ng/24h) Urine Endothelial Function Lipid Metabolism von Willebrand Factor (%) Blood Microalbumin (mg/24h) Urine Total Cholesterol (mg/dl) Blood HDL Cholesterol (mg/dl) LDL Cholesterol (mg/dl) Lung Function Triglycerides (mg/dl) FEV1 (% of predicted) FVC (% of predicted) Air Volume a Examples of some of the BOPHs, other biomarkers not listed include Hematological measures as well as markers of Metabolism, Cardiovascular, Renal and Hepatic function and enzymes 8 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

9 Questionnaire and Topography Demographics Diet and Consumption Physical Activity Employment Smoking History Fagerström Test for Nicotine Dependence and other questions Smoking Topography was measured using the CreSS Micro Device Puff Count Puff Volume Puff Duration Inter-Puff Interval 9 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

10 Outline Background Total Exposure Study Design and Conduct Comparisons between adult menthol and non-menthol smokers Demographics Biomarkers of Exposure Metabolite Ratios Biomarkers of Potential Harm Nicotine Dependence Scores Summary & Conclusions 10 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

11 Demographics a (N=1044) Non- (N=2297) Age (years, mean (SD)) 41.8 (12.1) 42.0 (13.0) Gender, No. (%) Female Male Race, No. (%) African-American White 664 (63.6%) 380 (36.4%) 448 (42.9%) 596 (57.1%) 1258 (54.8%) 1039 (45.2%) 166 (7.2%) 2131 (92.8%) BMI (kg/m 2 ), Mean (SD) (7.33) (6.29) CPD b, Mean (SD) 15.0 (8.7) 16.8 (9.0) Tar Yield (mg), Mean (SD) 10.4 (6.2) 8.5 (4.9) a 60 and 184 Non- Multiracial, Asian, Native American, Other and Missing values are not included; b Number of cigarettes smoked per day, based on number of butts returned 11 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

12 Demographics a - By Race Characteristics (N=596) Age (years), Mean (SD) 43.7 (12.9) Gender, No. (%) Female Male 419 (70.3%) 177 (29.7%) Whites Non- (N=2131) 41.9 (13.2) 1188 (55.8%) 943 (44.2%) African-Americans (N=448) Non- (N=166) 39.3 (10.5) 43.3 (10.9) 245 (54.7%) 203 (45.3%) 70 (42.2%) 96 (57.8%) CPD b, Mean (SD) 18.1 (9.2) 17.2 (9.1) 10.9 (5.7) 12.1 (7.4) Tar Yield (mg), Mean (SD) 8.9 (5.4) 8.7 (4.8) 12.8 (6.4) 5.9 (5.4) Years Smoking, Mean (SD) 23.8 (12.9) 22.4 (13.1) 17.0 (11.4) 21.7 (12.5) a 60 and 184 Non- Multiracial, Asian, Native American, Other and Missing values are not included; b Number of cigarettes smoked per day based on butts returned 12 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

13 Outline Background Total Exposure Study Design and Conduct Comparisons between adult menthol and non-menthol smokers Demographics Biomarkers of Exposure Metabolite Ratios Biomarkers of Potential Harm Nicotine Dependence Scores Summary & Conclusions 13 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

14 Biomarkers of Exposure (N=1044) Non- (N=2297) CPD 15.0 (8.7) 16.8 (9.0) Tar Yield (mg) 10.6 (6.2) 8.5 (4.9) NE (mg/24h) a 12.8 (7.8) 13.5 (7.9) Total NNAL (ng/24h) b (294.8) (309.5) Serum Cotinine (ng/ml) a (108.4) COHb (% Sat.) a 5.2 (2.27) (105.4) 5.4 (2.23) Data Shown as unadjusted Mean (SD); Number of evaluable observations varied for each biomarker; a Analysis based on publication by Wang et al 2009; b Unpublished data from additional analysis Overall, no statistically significant differences (p>0.05) in biomarkers of exposure were observed between menthol and non-menthol smokers 14 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

15 Biomarkers of Exposure By Race Whites African-Americans Biomarker (N=596) Non- (N=2131) (N=448) Non- (N=166) CPD 18.1 (9.2) 17.2 (9.1) 10.9 (5.7) 12.1 (7.4) Tar Yield (mg) 8.9 (5.4) 8.7 (4.8) 12.8 (6.4) 5.9 (5.4) NE (mg/24h) a 14.2 (8.4) 13.8 (7.9) 10.8 (6.4) 10.4 (7.1) Total NNAL (ng/24h) b (318.1) (313.8) (242.3) (215.4) COHb (% Sat.) a 5.5 (2.4) 5.4 (2.3) 4.7 (2.0) 4.8 (2.3) Serum Cot. (ng/ml) a (100.9) (104.1) (117.3) (120.3) Data Shown as unadjusted Mean (SD); Number of evaluable observations varied for each biomarker; a Analysis based on publication by Wang et al 2009 b Unpublished data from additional analysis Overall, no statistically significant differences (p>0.05) in biomarkers of exposure were observed between menthol and non-menthol smokers 15 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

16 Outline Background Total Exposure Study Design and Conduct Comparisons between adult menthol and non-menthol smokers Demographics Biomarkers of Exposure Metabolite Ratios Biomarkers of Potential Harm Nicotine Dependence Scores Summary & Conclusions 16 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

17 Major Metabolic Pathways of Nicotine in Humans N H N CH 3 CYP2A6, CYP2B6 CYP2E1 N H N CH 3 O CYP2A6 N H OH N O CH 3 Nicotine Cotinine trans-3'-hydroxycotinine UGT2B10 UGT2B17 UGT2B10 UGT2B17 H N Gluc N CH 3 H N Gluc N CH 3 O N H OGluc N O CH 3 Nicotine-N-Gluc Cotinine-Gluc trans-3'-hydroxycotinine-gluc 17 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

18 Overview of NNK Metabolism N O NNK NNK-N-oxide 6-hydroxyNNK NO N CH3 CYP2A6 CYP2A13 (Lungs) N α-hydroxylation metabolic activation pathways OH NNAL NO N CH3 NNAL-N-oxide UGT1A4 (N-Gluc) UGT1A10 (O-Gluc) UGT2B7 (O-Gluc) UGT2B10(N-Gluc) UGT2B17 (O-Gluc) HOOC HO HO - OOC O OH N O NNAL-O-Glucuronide O + N OH OH NO N CH3 NO N CH3 OH OH NNAL-N-Glucuronide Adapted from Stepanov et al Cancer Epidemiol Biomarkers Prev. 2008, 17: l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

19 Estimation of Metabolite Ratios Phase I Oxidation Metabolite Ratio 3OH Cot./Cot. Ratio = trans-3 -hydroxycotinine Cotinine Phase II Glucuronidation Metabolite Ratio Glucuronide Ratios = Glucuronide Conjugate Unconjugated Note: Higher ratio is indicative of rapid detoxification 19 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

20 Comparison of Metabolite Ratio Metabolite Ratio (N = 980) Non- (N = 2189) PHASE I Oxidation Metabolite Ratio 3OHC/Cot. Ratio Data Shown as LSMeans Overall, no statistically significant difference (p>0.05) in the metabolite ratio was observed between menthol and non-menthol smokers 20 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

21 Comparison of Metabolite Ratios Metabolite Ratios (N = 980) PHASE I Oxidation Metabolite Ratio Non- (N = 2189) 3OHC/Cot. Ratio PHASE II Glucuronidation Metabolite Ratios Nicotine Gluc. Ratio Cotinine Gluc. Ratio OHC Gluc. Ratio NNAL Gluc. Ratio Data Shown as LSMeans; Number of evaluable observations varied for each ratio Overall, no statistically significant differences (p>0.05) in metabolite ratios were observed between menthol and non-menthol smokers 21 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

22 Comparisons of Metabolite Ratio - By Race (N = 566) Whites PHASE I Oxidation Metabolite Ratio Non- (N = 2028) African-Americans (N = 414) Non- (N = 161) 3OHC/Cot. Ratio Data Shown as LSMeans Overall, no statistically significant difference (p>0.05) in the metabolite ratio was observed between menthol and non-menthol smokers 22 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

23 Comparisons of Metabolite Ratios By Race (N = 566) Whites PHASE I Oxidation Metabolite Ratio Non- (N = 2028) African-Americans (N = 414) Non- (N = 161) 3OHC/Cot. Ratio PHASE II Glucuronidation Metabolite Ratios Nicotine Gluc. Ratio Cotinine Gluc. Ratio 3.86* OHC Gluc. Ratio NNAL Gluc. Ratio Data Shown as LSMeans; * p = for cotinine glucuronide ratio between White menthol and non-menthol cigarette smokers; Number of evaluable observations varied for each ratio Overall, no statistically significant differences (p>0.05) in all but one metabolite ratios were observed between menthol and non-menthol smokers 23 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

24 Statistical Model for Serum Cotinine Parameter F-ratio p-value Number of CPD <.0001 Tar Yield 56.7 <.0001 BMI 39.4 < OHC/Cot Ratio 27.4 <.0001 Cotinine Gluc. Ratio 22.2 <.0001 Puff duration 20.2 <.0001 Gender Race Age Alcohol consumption 8.2 <.0001 Total puff volume Race ) CPD was the most important statistically significant parameter (p<.0001) for Serum Cotinine. 2) did not have a statistically significant (p>0.05) contribution on Serum Cotinine. F-ratio = Effect Mean Square/Residual Mean Square; The parameters were prioritized based on F-ratio; R 2 = l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

25 The clinical relevance of the differences in metabolism is uncertain Exposure and detoxification of NNK are unlikely to explain, by themselves, the differences in lung cancer risk among the three populations studied. (Derby, et al. 2009) ated cigarette smoking inhibits the metabolism of nicotine, but the consequences of this with respect to addiction or health effects is unclear. (Benowitz, et al. 2008) Inhibition of a single pathway may not have a significant impact on overall exposure since multiple isoforms are involved and alternate pathways are available e.g. Only 14-17% of NNK is converted to NNAL (Hecht, et al. 2008) 25 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

26 Summary Based on the selected biomarkers of exposure investigated, cigarette smoke exposure in adult menthol smokers was not statistically significantly different compared to that observed in non-menthol smokers does not appear to inhibit the metabolism of nicotine or NNK 26 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

27 Outline Background Total Exposure Study Design and Conduct Comparisons between adult menthol and non-menthol smokers Demographics Biomarkers of Exposure Metabolite Ratios Biomarkers of Potential Harm Nicotine Dependence Scores Summary & Conclusions 27 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

28 Biomarkers of Potential Harm Biomarkers of oxidative stress, inflammation, endothelial function, coagulation, lipid metabolism and metabolic function were investigated. 28 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

29 Biomarkers of Potential Harm a Biomarker Mean (SD) Non- Mean (SD) HDL Cholesterol (mg/dl) 52.6 (15.3) 51.0 (16.3) 3.01 LDL Cholesterol (mg/dl) 114 (36.4) 116 (36.3) Oxidized LDL (U/L) 73.5 (21.4) 74.5 (21.0) Total Cholesterol (mg/dl) 194 (42.3) 198 (41.6) Triglycerides (mg/dl) 142 (106) 164 (141) hs C-Reactive Protein (mg/l) 2.91 (2.69) 2.69 (2.55) 8.14 FEV1 (% predicted) 83.5 (19.0) 84.1 (18.0 ) epi-Prostaglandin-F2α (ng/24h) 1882 (1082) 1893 (1040) dehydrothromboxane-B2 (ng/24h) 1397 (1016) 1310 (1045) 6.64 White Blood Cells (x1000/ul) 7.74 (2.33) 8.05 (2.27) Percent Difference a Selected biomarkers shown in this table 29 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

30 Biomarkers of Potential Harm (BOPH) had no statistically significant effect (p>0.05) on the biomarkers of potential harm investigated. The highest ranking statistically significant factors were: BMI, CPD, Age, Gender, Number of years smoked All the statistically significant factors accounted for 4-26% a of the variability in BOPHs investigated a except for Leptin (R 2 =0.6) which was primarily driven by BMI 30 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

31 Outline Background Total Exposure Study Design and Conduct Comparisons between adult menthol and non-menthol smokers Demographics Biomarkers of Exposure Metabolite Ratios Biomarkers of Potential Harm Nicotine Dependence Scores Summary & Conclusions 31 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

32 Fagerström Test for Nicotine Dependence (FTND) Non- Smokers 363 Smokers Number of participants FTND Score smokers do not appear to have higher FTND scores 32 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

33 Fagerström Test for Nicotine Dependence (FTND) Categorization of FTND Scores Five Categories (Very Low: 0-2 points, Low: 3-4 points, Medium: 5 points, High: 6-7 points, Very High: 8-10 points) Three Categories (Low (0-3), Medium (4-5) and High (6-10) scores) Two Categories (Low/Medium (0-5) and High (6-10) scores) Status Non- Non- Non- a Adjusted for age, race, gender, education and tar yield category. Adjusted a Odds Ratio % CI Reference Reference Reference Overall, no statistically significant differences (p>0.05) in FTND scores were observed between menthol and non-menthol smokers a Adjusted for age, race, gender, education and tar yield category. 33 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

34 Time to First Cigarette (TTFC) Categorization of TTFC Status Adjusted a Odds Ratio 95% CI Four Categories (< 5 mins, 6-30 mins, mins and > 60 mins.) Non Reference Two Categories (< 30 mins and > 30 mins) Non Reference a Adjusted for age, race, gender, education and tar yield category. Overall, no statistically significant differences (p>0.05) in time to first cigarette were observed between menthol and non-menthol smokers 34 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

35 Outline Background Total Exposure Study Design and Conduct Comparisons between adult menthol and non-menthol smokers Demographics Biomarkers of Exposure Metabolite Ratios Biomarkers of Potential Harm Nicotine Dependence Scores Summary & Conclusions 35 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

36 Summary Based on the selected biomarkers of exposure investigated, cigarette smoke exposure in adult menthol smokers was not statistically significantly different compared to that observed in non-menthol smokers does not appear to inhibit the metabolism of nicotine or NNK 36 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

37 Summary The biomarkers of potential harm investigated were not statistically significantly different in adult menthol cigarette smokers compared to non-menthol cigarette smokers cigarette smokers did not have higher Fagerström Test for Nicotine Dependence scores compared to non-menthol cigarette smokers The collective evidence from the TES is in agreement with the epidemiological reports that adult menthol cigarette smokers are not at a greater risk of smoking-related diseases compared to adult nonmenthol smokers 37 l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010

38 References Ahijevych, K., Gillespier, J., Demirci, M., Jagadeesh, J. (1996). and nonmenthol cigarettes and smoke exposure in black and white women. Pharmacology Biochemistry and Behavior 53(2): Ahijevych, K., Dal, G., & Chan, K. (2002). pharmacokinetics in African American women following menthol cigarette smoking [abstract]. American Thoracic Society International Conference, May 17-22, Atlanta, GA. Benowitz, N.L., Herrera, B., & Jacob III, P. (2004). ated cigarette smoking inhibits nicotine metabolism. Journal of Pharmacology and Experimental Therapeutics 310(3): Benowitz, N.L., Lessov-Schlaggar, C.N., Swan, G.E. (2008). Genetic influences in the variation in renal clearance of nicotine and cotinine. Clinical Pharmacology & Theraputics 84(2): Berg, J.Z., Mason, J., Boettcher, A.J., Hatsukami, D.K., & Murphy, E.W. (2010). Nicotine metabolism in African Americans and European Americans: Variation in glucuronidation by ethnicity and UGT2B10 haplotype. Journal of Pharmacology and Experimental Therapeutics 332(1): Derby, K.S., Cuthrell, K., Caberto, C., Carmella, S., Murphy, S.E., Hecht, S.S., & Le Marchand, L. (2009). Exposure to the carcinogen 4- (methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in smokers from 3 populations with different risks of lung cancer. International Journal of Cancer 125(10): Hecht, S.S., Carmella, S.G., Stepanov, I., Jensen, J., Anderson, A., Hatsukami, D.K. (2008). Metabolism of the tobacco-specific carcinogen 4- (methylnitrosamino)-1-(3-pyridyl)-1-butanone to its biomaker total NNAL in smokeless tobacco users. Cancer Epidemiology Biomarkers and Prevention. 17(3): Heck, J.D. (2009). Smokers of menthol and nonmenthol cigarettes exhibit similar levels of biomarkers of smoke exposure. Cancer Epidemiology Biomarkers and Prevention 18(2): Muscat, J.E. Chen, G., Knipe, A., Stellman, S.D., Lazarus, P., & Richie, J. (2009). Effects of menthol on tobacco smoke exposure nicotine dependence, and NNAL glucuronidation. Cancer Epidemiology Biomarkers and Prevention 18(1): Patterson, F., Benowitz, N., Shields, P., Kaufmann, V., Jepson, C., Wileyto, P., Kucharski, S., Lerman, C. (2003). Individual differences in nicotine intake per cigarette. Cancer Epidemiology Biomarkers and Prevention. 12(5): Richie, J.P., Jr., Carmella, S.G., Muscat, J.E., Scott, D.G., Akerkar, S.A. & Hecht, S.S. (1997). Differences in the urinary metabolites of the tobaccospecific lung carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in black and white smokers. Cancer Epidemiology Biomarkers and Prevention 6(10): Rosenblatt, M.R., Olmstead, R.E., Iwamoto-Schaap, P.N. & Jarvik, M.E. (1998). Olfactory thresholds for nicotine and menthol in smokers (abstinent and nonabstinent) and nonsmokers. Physiology and Behavior 65(3): Stepanov, I., Upadhyaya,P., Carmella, S.G., Feuer, R., Jensen, J., Hatsukami, D.K., Hecht, S.S. (2008). Extensive metabolic activation of the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in smokers. Cancer Epidemiology Biomarkers and Prevention. 17(7): Wang, J., Roethig, H., Appleton, S., Werley, M.S., Muhammad-Kah, R., & Mendes, P. (2009). The effect of menthol containing cigarettes on adult smokers exposure to nicotine and carbon monoxide. Regulatory Toxicology and Pharmacology 57(1): l Altria Client Services (on behalf of Philip Morris USA) l Presentation to the Tobacco Products Scientific Advisory Committee l July 15-16, 2010