Cannabis and Work: The Need for More ResearchPosted on by
Cannabis sativa has been used for a wide variety of industrial, medical, and non-medical uses for thousands of years, yet remains a source of controversy across the fields of medicine, law, and occupational safety1-5. Access to and consumption of cannabis have increased as a result of more favorable public attitudes and state access laws. Nearly 18 percent of full-time workers and 21 percent of part-time workers used cannabis in 20186. Lifetime, past-year, and past-month use among full-time workers all increased from 2017 to 20186. The implications and challenges of increasing cannabis consumption by workers requires urgent and critical research attention. These issues are discussed in a new commentary, Cannabis and work: Need for more research, in the American Journal of Industrial Medicine. A summary is provided below.
Uses and Health Effects
Cannabis sativa contains 120 cannabinoids, only two of which have been studied for medical use: delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD)7-9. THC produces psychoactive effects in consumers and is responsible for the “high” associated with cannabis10,11. CBD is non-intoxicating and has potential therapeutic properties, but clinical data to support its medical benefits is limited12-14. Typical cannabis products, prepared from the flowering tops of the unfertilized female plant, contain 7 to 14 percent THC7. Medical cannabis sold in dispensaries has a similar THC concentration to cannabis sold for non-medical use15.
Cannabis was widely used for a variety of medical ailments throughout the 19th and early 20th centuries, until a series of federal laws beginning in the 1930s penalized the sale and use of medicinal cannabis and ended its legitimate medical use16. However, pharmaceutical-grade cannabis products have recently been approved by the U.S. Food and Drug Administration for the treatment of childhood epilepsy syndromes, as well as nausea and vomiting associated with a variety of conditions17-20. Cannabis is also consumed for enjoyment and without medical justification, using a variety of products with varying potency levels and routes of administration. In addition to a variety of acute health effects, including dizziness, dry mouth, nausea, vomiting, drowsiness, euphoria, disorientation, confusion, loss of balance, and hallucination21, chronic use in some individuals can result in cannabis use disorder (CUD). CUD is characterized by dependence, withdrawal symptoms, failure to meet work, school, or home responsibilities, tolerance to greater amounts of cannabis, and other qualifying symptoms22-25.
Cannabis and Workplace Injury
Increasing access to and consumption of cannabis by workers have led to increased concerns about workplace safety4,26-29. Research is needed to explore the incidence of cannabis consumption by industry and occupation, as well as the relationship between cannabis consumption by workers and occupational injuries. Such research should consider temporal relationship between consumption and injury, confounding variables (e.g. gender, safety climate, training, and fatigue), and factors potentially influencing work impairment from cannabis consumption, including timing, intensity, duration, potency, and route of administration30. Cannabis industry workers face unique workplace safety and health risks, including exposures to chemical, biological, and physical hazards31. Exposures may also affect law enforcement, fire fighters, emergency medical technicians, and hazardous materials response personnel working around cannabis or responding to cannabis industry sites32-34.
Cannabis, Occupational Driving, and Job Impairment
Even though there has been considerable research about cannabis consumption, driver performance, and vehicular crashes indicating that driving under the influence of cannabis does increase the risk of traffic crashes24,26,28,35-38, further research is needed to determine the prevalence of cannabis consumption by workers who drive as part of their job. Determining driver impairment from cannabis consumption also remains a complicated but critical research need.
Since cannabis is stored in body fat and released into the bloodstream over days or weeks from the time of actual consumption, THC levels detected in a positive urine or blood drug test do not permit sound inferences about the frequency of cannabis consumption, specific time of last use, or cannabis-related impairment39-42. Impairment testing provides a promising adjunct or alternative to traditional workplace drug testing that would evaluate real-time deficits in job performance from multiple causes, such as lack of sleep, chronic medical conditions, effect from physician-prescribed medications, and self-prescribed drugs, including cannabis. Some impairment tests are modeled after traditional field sobriety tests used by law enforcement43, and newer digital tests are available as applications that resemble video games44. More intervention studies are needed to validate the effectiveness of workplace impairment testing methodologies.
Workplace Supported Recovery
Workplace programs that provide access to support, counseling, and treatment can be an important means to achieve recovery from all substance use disorders, including CUD, while maintaining employment—a key goal for workers in recovery45. The 2020 U.S. National Drug Control Strategy encourages “workplace support for current employees in treatment and recovery,” which may reduce the stigma associated with substance use disorders and lower barriers to seeking and receiving care46. Workplace Supported Recovery programs aim to prevent work-related exposures that may contribute to substance use disorders and provide access to support and treatment for workers in recovery.
In 1970, the Controlled Substances Act (CSA) consolidated all federal laws that regulated controlled substances47, making it unlawful to manufacture, distribute, dispense, or possess a controlled substance (21 U.S.C.§841(a)), including cannabis. However, shifting public attitudes have led 33 states, along with the District of Columbia, to approve access laws that make cannabis available to consumers with qualifying medical conditions48. Eleven states, and the District of Columbia, allow consumer access to cannabis for medical and non-medical use48. Additionally, many states have passed laws decriminalizing the possession and use of small amounts of cannabis and expunging or vacating criminal records for qualifying cannabis convictions49. As the debate over national legalization of cannabis continues, so does the uncertainty regarding cannabis and workplace drug testing programs, workplace substance use policies, worker’s compensation claims, and employment litigation.
Need for More Research
As the legal and cultural landscapes of cannabis access and consumption continue to evolve, implications for workplace policies, programs, and practices become more salient. Critical research attention should be focused on these implications and the challenges surrounding cannabis and work. Among these research challenges are the following:
- data about industries and occupations where cannabis consumption among workers is most prevalent;
- adverse health consequences of cannabis consumption among workers;
- relationship between cannabis consumption and occupational injuries;
- hazards to workers in the emerging cannabis industry;
- cannabis consumption and its effect on occupational driving;
- ways to assess performance deficits and impairment from cannabis consumption;
- workplace supported recovery programs; and
- ways to craft workplace policies and practices that take into consideration conflicting state and federal laws pertaining to cannabis.
How has your workplace addressed issues surrounding cannabis? Please share with us in the comment section below.
Jamie Osborne, MPH, CHES® is a Public Health Analyst with the NIOSH Office of the Director.
John Howard, MD, is the Director of the National Institute for Occupational Safety and Health (NIOSH).
- Lapoint JM. Cannabinoids. In: Hoffman RS, Howland MA, Lewin NA, Nelson LS, Goldfrank LR, eds. Goldfrank’s Toxicologic Emergencies. 10th ed. New York, NY: McGraw‐Hill; 2015:1042‐1053.
- Russo EB. History of cannabis and its preparations in saga, science, and sobriquet. Chem Biodivers. 2007;4(8):1614‐1648. https://onlinelibrary.wiley.com/doi/abs/10.1002/cbdv.200790144
- Bennett C. Early/ancient history. In: Holland J, ed. The Pot Book: A Complete Guide to Cannabis. Rochester, NY: Vermont: Park Street Press; 2010:17‐26.
- Goldsmith RS, Targino MC, Fanciullo GJ, et al. Medical marijuana in the workplace: challenges and management options for occupational physicians. J Occup Environ Med. 2015;57(5):518‐525. https://journals.lww.com/joem/Fulltext/2015/05000/Medical_Marijuana_in_the_Workplace__Challenges_and.6.aspx
- Solomon R. Racism and its effect on cannabis research. Cannabis Cannabinoid Res. 2020;5(1):2‐5. https://www.liebertpub.com/doi/10.1089/can.2019.0063
- Substance Abuse and Mental Health Services Administration. Results from the 2018 National Survey on Drug Use and Health: Detailed Tables. Section 7 Prevalence Estimates Tables. 2019. https://www.samhsa.gov/data/sites/default/files/cbhsq-reports/NSDUHDetailedTabs2018R2/NSDUHDetTabsSect7pe2018.htm
- Welch SP, Smith TH, Malcolm R, Lichman AH. The pharmacology of cannabinoids. In: Miller SC, Fiellin DA, Rosenthal RN, Saitz R, eds. The ASAM Principles of Addiction Medicine. 6th ed. Philadelphia, PA:Wolters‐Kluwer; 2019:208‐229.
- Pertwee RG. Endocannabinoids and their pharmacological actions. Handb Exp Pharmcol. 2015;231:1‐37. https://link.springer.com/chapter/10.1007%2F978-3-319-20825-1_1
- VanDolah HJ, Bauer BA, Mauck KF. Clinician’s guide to cannabidiol and hemp oils. Mayo Clin Proc. 2019;94(9):1840‐1851. https://www.sciencedirect.com/science/article/pii/S0025619619300072?via%3Dihub
- Mechoulam R, Harius LO, Pertwee R, Howlett AC. Early phytocannabinoid chemistry to endocannabinoids and beyond. Nat Rev Neurosci. 2014;15(11):757‐764. https://www.nature.com/articles/nrn3811
- Wu I. Cannabis, cannabinoid receptors, and endocannabinoid system: yesterday, today, and tomorrow. Act Pharmacol Sin. 2019;40(3):297‐299. https://www.nature.com/articles/s41401-019-0210-3
- World Health Organization (WHO). Cannabidiol (CBD): World Health Organisation Expert Committee on Drug Dependence Thirty‐Ninth Meeting. 2017. https://www.who.int/medicines/access/controlled-substances/5.2_CBD.pdf
- Eisenstein M. The reality behind cannabidiol’s medical hype. Nature. 2019;572:S2‐S4. https://www.nature.com/articles/d41586-019-02524-5
- Levinsohn EA, Hill KP. Clinical uses of cannabis and cannabinoids in the United States. J Neurol Sci. 2020;411:116717‐116723. https://www.sciencedirect.com/science/article/pii/S0022510X20300538?via%3Dihub
- Cash MC, Cunnane K, Romero‐Sandoval EA. Mapping cannabis potency in medical and recreational programs in the United States. PLoS One. 2020;25(3):e023167. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0230167
- Baron EP. Comprehensive review of medicinal marijuana, cannabinoids, and therapeutic implications in medicine and headache: what a long strange trip it’s been. Headache. 2015;55(6):885‐916. https://headachejournal.onlinelibrary.wiley.com/doi/full/10.1111/head.12570
- U.S. Food and Drug Administration. FDA and Cannabis: Research and Drug Approval Process. January 14, 2020. https://www.fda.gov/news-events/public-health-focus/fda-and-cannabis-research-and-drug-approval-process
- Badowksi ME, Yanful PK. Dronabinol oral solutions in the management of anorexia and weight loss in AIDS and cancer. Ther Clin Risk Manag. 2018;14:643‐651. https://www.dovepress.com/dronabinol-oral-solution-in-the-management-of-anorexia-and-weight-loss-peer-reviewed-article-TCRM
- Pergolizzi JV, Taylor R, LeQuang JA, Zampogna G, Raffa RB. Concise review of the management of iatrogenic emesis using cannabinoids: emphasis on nabilone for chemotherapy‐induced nausea and vomiting. Cancer Chemother Pharmacol. 2017;79(3):467‐477. https://link.springer.com/article/10.1007/s00280-017-3257-1
- Abu‐Sawwa R, Stehling C. Epidiolex (cannabidiol) primer: frequently asked questions for patients and caregivers. J Pediatr Pharmacol Ther.2020;25(1):75‐77. https://www.jppt.org/doi/10.5863/1551-6776-25.1.75
- Whiting PF, Wolff RF, Deshpande S, et al. Cannabinoids for medical use: a systematic review and meta‐analysis. JAMA. 2015;313(24):2456‐2773. https://jamanetwork.com/journals/jama/fullarticle/2338251
- Hasin DS, Saha TD, Kerridge BT, et al. Prevalence of marijuana use disorders in the United States between 2001‐2002 and 2012‐2013. JAMA Psychiatry. 2015;72(12):1235‐1242. https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2464591
- Sherman BJ, McRae‐Clark AL. Treatment of cannabis use disorder: current science and outlook. Pharmacol. 2016;36(5):511‐535. https://accpjournals.onlinelibrary.wiley.com/doi/full/10.1002/phar.1747
- Hasin DS. US epidemiology of cannabis use and associated problems. Neuropsychopharmacol. 2018;43:195‐212. https://www.nature.com/articles/npp2017198
- Patel J, Marwaha R. Cannabis use disorder. National Library of Medicine. Bethesda, MD: StatPearls Publishing; June 5, 2019. https://www.ncbi.nlm.nih.gov/books/NBK538131/?report=printable https://www.ncbi.nlm.nih.gov/books/NBK538131/?report=printable
- Phillips JA, Holland MG, Baldwin DD, et al. Marijuana in the workplace: guidance for occupational health professionals and employers. Joint guidance statement from the American Association of Occupational Health Nurses and the American College of Occupational and Environmental Medicine. Workplace Health Saf. 2015;63(4):139‐164. https://doi.org/10.1177/2165079915581983
- Parnes JE, Bravo AJ, Conner BT, Pearson MR. A burning problem: cannabis lessons learned from Colorado. Addict Res Theory. 2018;26(1):3‐10. https://www.tandfonline.com/doi/full/10.1080/16066359.2017.1315410
- Hartman RJ, Huestis MA. Cannabis effects on driving skills. Clin Chem. 2013;59(3):478‐492. https://academic.oup.com/clinchem/article/59/3/478/5621997
- Desrosiers NA, Ramaekers JG, Chauchard E, Gorelick DA, Huestis MA. Smoked cannabis’ psychomotor and neurocognitive effects in occasional and frequent smokers. J Anal Toxicol. 2015;39(4):251‐261. https://academic.oup.com/jat/article/39/4/251/750800
- Biasutti WR, Leffers KSH, Callaghan RC. Systematic review of cannabis use and risk of occupational injury [published online ahead of print May 22, 2020]. Subst Use Misuse. 2020. https://www.tandfonline.com/doi/full/10.1080/10826084.2020.1759643
- Colorado Department of Public Health and Environment. Guide to worker safety and health in the marijuana industry. Denver, CO: State of Colorado; 2017. https://deohs.washington.edu/sites/default/files/documents/Guide-to-Worker-Safety-and-Health-in-the-Marijuana-Industry_FULL-REPORT.pdf
- Wiegand DM, Methner MM, Grimes R. Evaluation of police officers’ exposure to secondhand cannabis smoke at open‐air stadium events. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Health Hazard Evaluation Report 2017‐0174‐3335; March, 2019. https://www.cdc.gov/niosh/hhe/reports/pdfs/2017-0174-3335.pdf
- Fent K, Durgam S, West C, Gibbins J, Smith J. Evaluation of police officer’s exposures to chemicals while working inside a drug vault— Kentucky. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, HHE Report No. 2010‐0017‐3133; July 2011 https://www.cdc.gov/niosh/hhe/reports/pdfs/2010-0017-3133.pdf
- Vernon A. Marijuana: a growing hazard on the fireground. Firehouse. July 10, 2009. https://www.firehouse.com/safety-health/article/10471249/marijuana-a-growing-hazard-on-the-fireground
- Berghaus G, et al. Meta‐analysis of empirical studies concerning the effects of medicines and illegal drugs including pharmacokinetics on safe driving. DRUID 6th Framework Programme: Germany: European Commission under the Transport RTD Programme of the 6th Framework Programme, 2011;168‐172. https://www.bast.de/Druid/EN/deliverales-list/downloads/Deliverable_1_1_2_B.pdf?__blob=publicationFile&v=1
- Asbridge M, Hayden JA, Cartwright JL. Acute cannabis consumption and motor vehicle collision risk: systematic review of observational studies and meta‐analysis. Brit Med J. 2012:344. https://www.bmj.com/content/344/bmj.e536
- Asbridge M, Mann R, Cusimano MD, et al. Cannabis and traffic collision risk: findings from a case‐crossover study of injured drivers presenting to emergency departments. Int J Public Health. 2014;59:395‐404. https://link.springer.com/article/10.1007%2Fs00038-013-0512-z
- Rogeberg O, Elvik R. The effects of cannabis intoxication on motor vehicle collisions revisited and revised. Addict. 2016;111:1348‐1359. https://onlinelibrary.wiley.com/doi/full/10.1111/add.13347
- Reisfield GM, Goldberger BA, Gold MS, DuPont RL. The mirage of impairing drug concentration thresholds: a rationale for zero tolerance per se driving under the influence of drug laws. J Anal Toxicol.2012;36:353‐356. https://academic.oup.com/jat/article/36/5/353/746140
- Frone MR. Workplace interventions I: drug testing job applicants and employees. In: Frone MR, ed. Alcohol and Illicit Drug Use in the Workforce and Workplace. Washington, DC: American Psychological Association; 2013:143‐175. https://psycnet.apa.org/record/2012-14634-006
- Reisfield GM, Bertholf RL, Goldberger BA, DuPont RL. Practical considerations in drug testing. In: Miller SC, Fiellin DA, Rosenthal RN, Saitz E, eds. The ASAM Principles of Addiction Medicine. 6th ed. Philadelphia, PA: Wolters‐Kluwer; 2019:1752‐1767.
- Macdonald S, Hall W, Roman P, Stockwell T, Coghlan M, Nesvaag S. Testing for cannabis in the workplace: a review of the evidence. Addiction. 2010;105:408‐416. https://onlinelibrary.wiley.com/doi/full/10.1111/j.1360-0443.2009.02808.x
- Schroth LA, Hody BJ, Chaffin CS, Laratonda E, Cook GW. Medical marijuana. Addressing impairment in the workplace. Prof Saf. 2018;63(8):36‐40. https://www.onepetro.org/journal-paper/ASSE-18-08-36
- Ferguson BA, Lauriski DR, Huecker M, Wichmann M, Shreffler J, Shoff H. Testing alertness of emergency physicians: a novel quantitative measure of alertness and implication for worker and patient care. J Emerg Med. 2020;58(2):514‐519. https://www.sciencedirect.com/science/article/pii/S0736467919309369?via%3Dihub
- Laudet AB. Rate and predictors of employment among formerly polysubstance dependent urban individuals in recovery. J Addict Dis. 2012;31(3):288‐302. https://www.tandfonline.com/doi/full/10.1080/10550887.2012.694604
- National Drug Control Strategy. National Treatment Plan for Substance Use Disorder 2020. Washington, DC: Office of National Drug Control Policy February, 2020; 2020. https://www.whitehouse.gov/wp-content/uploads/2020/02/2020-NDCS-Treatment-Plan.pdf
- Controlled Substances Act. 21 U.S.C. § 801 et seq. (Pub. L. 91‐513). https://uscode.house.gov/view.xhtml?path=/prelim@title21/chapter13&edition=prelim
- National Conference of State Legislatures. State Medical Marijuana Laws. March 10, 2020. https://www.ncsl.org/research/health/statemedical-marijuana-laws.aspx
- Marijuana Overview. National Conference of State Legislatures. October 17, 2019. https://www.ncsl.org/research/civil-and-criminaljustice/marijuana-overview.aspx