Research Summary

I am a toxicologist who conduct clinical pharmacology studies to understand the harms or benefits of novel tobacco products and the pharmacological interaction between cannabis and tobacco when co-administered.

Research Funding

  • September 19, 2013 - June 30, 2023 - Integrated Health, Behavioral and Economic Research on Current and Emerging Tobacco Products , Co-Investigator . Sponsor: NIH, Sponsor Award ID: 9U54HL147127-06
  • August 15, 2018 - July 31, 2022 - Cigarette Harm Reduction with Scheduled Electronic Cigarette Use , Co-Investigator . Sponsor: NIH, Sponsor Award ID: U01DA045519
  • June 1, 2016 - May 31, 2017 - Clinical Pharmacology of Electronic Cigarettes , Co-Investigator . Sponsor: NIH, Sponsor Award ID: 3R01DA039264-02S1

Education

Livingstone College, Salisbury, NC, B.S., 05/2006, Biology
University of Georgia, Athens, GA, Ph.D., 08/2011, Toxicology
University of California, San Francisco, CA, Postdoc, 12/2014, Tobacco Control and Research

Honors & Awards

  • 2003-2006
    Academic Gold Medal, Livingstone College
  • 2006
    Summer Bridge Fellow, University of Georgia
  • 2012
    Society for Research on Nicotine and Tobacco Travel Award
  • 2012
    Centers for Disease Control and Prevention (CDC) Top-Ten Research Article

Selected Publications

  1. St Helen G. Commentary on Keller-Hamilton et al. : Oral nicotine pouches provide a less controversial route for tobacco harm reduction than electronic cigarettes. Addiction. 2024 03; 119(3):476-477.  View on PubMed
  2. Giberson J, Nardone N, Addo N, Khan S, Jacob P, Benowitz N, St Helen G. Nicotine Intake in Adult Pod E-cigarette Users: Impact of User and Device Characteristics. Nicotine Tob Res. 2023 Jul 14; 25(8):1489-1495.  View on PubMed
  3. Wold LE, Tarran R, Crotty Alexander LE, Hamburg NM, Kheradmand F, St Helen G, Wu JC, American Heart Association Council on Basic Cardiovascular Sciences; Council on Arteriosclerosis, Th. Cardiopulmonary Consequences of Vaping in Adolescents: A Scientific Statement From the American Heart Association. Circ Res. 2022 07 22; 131(3):e70-e82.  View on PubMed
  4. Jacob P, Chan L, Cheung P, Bello K, Yu L, StHelen G, Benowitz NL. Minor Tobacco Alkaloids as Biomarkers to Distinguish Combusted Tobacco Use From Electronic Nicotine Delivery Systems Use. Two New Analytical Methods. Front Chem. 2022; 10:749089.  View on PubMed
  5. Chaffee BW, Halpern-Felsher B, Jacob P, St Helen G. Biomarkers of nicotine exposure correlate with the Hooked on Nicotine Checklist among adolescents in California, United States. Addict Behav. 2022 05; 128:107235.  View on PubMed
  6. Benowitz NL, St Helen G, Liakoni E. Clinical Pharmacology of Electronic Nicotine Delivery Systems (ENDS): Implications for Benefits and Risks in the Promotion of the Combusted Tobacco Endgame. J Clin Pharmacol. 2021 08; 61 Suppl 2:S18-S36.  View on PubMed
  7. Benowitz NL, St Helen G, Nardone N, Addo N, Zhang JJ, Harvanko AM, Calfee CS, Jacob P. Twenty-Four-Hour Cardiovascular Effects of Electronic Cigarettes Compared With Cigarette Smoking in Dual Users. J Am Heart Assoc. 2020 12; 9(23):e017317.  View on PubMed
  8. Yao T, Sung HY, Huang J, Chu L, St Helen G, Max W. The impact of e-cigarette and cigarette prices on e-cigarette and cigarette sales in California. Prev Med Rep. 2020 Dec; 20:101244.  View on PubMed
  9. Carroll DM, Cigan S, Ikuemonisan J, Hammonds T, Stepanov I, St Helen G, Benowitz N, Hatsukami DK. Relationships Between Race, Gender, and Spot Urine Levels of Biomarkers of Tobacco Exposure Vary Based on How Creatinine Is Handled in Analyses. Nicotine Tob Res. 2020 10 29; 22(11):2109-2113.  View on PubMed
  10. Kovar L, Selzer D, Britz H, Benowitz N, St Helen G, Kohl Y, Bals R, Lehr T. Comprehensive Parent-Metabolite PBPK/PD Modeling Insights into Nicotine Replacement Therapy Strategies. Clin Pharmacokinet. 2020 09; 59(9):1119-1134.  View on PubMed
  11. St Helen G. A ban targeting only open-system e-cigarettes is unlikely to prevent a future EVALI-like outbreak among e-cigarette users. Addiction. 2021 05; 116(5):995-997.  View on PubMed
  12. Liakoni E, Nardone N, St Helen G, Dempsey DA, Tyndale RF, Benowitz NL. Effects of Nicotine Metabolic Rate on Cigarette Reinforcement. Nicotine Tob Res. 2020 07 16; 22(8):1419-1423.  View on PubMed
  13. Jacob P, St Helen G, Yu L, Nardone N, Havel C, Cheung P, Benowitz NL. Biomarkers of Exposure for Dual Use of Electronic Cigarettes and Combustible Cigarettes: Nicotelline, NNAL, and Total Nicotine Equivalents. Nicotine Tob Res. 2020 06 12; 22(7):1107-1113.  View on PubMed
  14. Harvanko AM, St Helen G, Nardone N, Addo N, Benowitz NL. Twenty-four-hour subjective and pharmacological effects of ad-libitum electronic and combustible cigarette use among dual users. Addiction. 2020 06; 115(6):1149-1159.  View on PubMed
  15. Benowitz NL, St Helen G, Nardone N, Cox LS, Jacob P. Urine Metabolites for Estimating Daily Intake of Nicotine From Cigarette Smoking. Nicotine Tob Res. 2020 02 06; 22(2):288-292.  View on PubMed
  16. St Helen G, Nardone N, Addo N, Dempsey D, Havel C, Jacob P, Benowitz NL. Differences in nicotine intake and effects from electronic and combustible cigarettes among dual users. Addiction. 2020 04; 115(4):757-767.  View on PubMed
  17. Nardone N, Jain S, Addo N, St Helen G, Jacob P, Benowitz NL. Sources and Biomarkers of Secondhand Tobacco Smoke Exposure in Urban Adolescents. Acad Pediatr. 2020 May - Jun; 20(4):493-500.  View on PubMed
  18. St Helen G, Liakoni E, Nardone N, Addo N, Jacob P, Benowitz NL. Comparison of Systemic Exposure to Toxic and/or Carcinogenic Volatile Organic Compounds (VOC) during Vaping, Smoking, and Abstention. Cancer Prev Res (Phila). 2020 02; 13(2):153-162.  View on PubMed
  19. Benowitz N, Nardone N, St Helen G, Addo N, Jacob P, Liakoni E, Jain S, Hooshfar S, Lynch K. Quantitative biochemical screening for marijuana use and concordance with tobacco use in urban adolescents. Drug Alcohol Depend. 2019 12 01; 205:107583.  View on PubMed
  20. Liakoni E, St Helen G, Dempsey DA, Jacob P, Tyndale RF, Benowitz NL. Relationship between skin melanin index and nicotine pharmacokinetics in African American smokers. Drug Alcohol Depend. 2019 11 01; 204:107474.  View on PubMed

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