A groundbreaking study from the University of Canterbury (UC) has concluded that vaping is likely to cause lung and oral cancer, marking a significant contribution to public health research from New Zealand's higher education sector. Led by Professor Ian Shaw from UC's School of Physical and Chemical Sciences, the research provides the strongest evidence yet that chemicals in "vape smoke"—the aerosol produced when e-liquids are heated—pose a carcinogenic threat, albeit lower than traditional cigarettes. This finding underscores the pivotal role of university-led investigations in addressing emerging health challenges in Aotearoa New Zealand.
The paper, titled "Is it safe to vape? Assessing the carcinogenic risk of 'vape smoke'," was published on 17 April 2026 in the New Zealand Medical Journal (DOI: 10.26635/6965.7434). It arrives amid growing concerns over youth vaping rates and tightening regulations, positioning UC at the forefront of evidence-based discourse on e-cigarette safety.
Background on the University of Canterbury's Research Team
The University of Canterbury, located in Christchurch, has long been a hub for health and toxicology research in New Zealand. Professor Ian C. Shaw, the lead author, is a distinguished toxicologist whose work spans food safety, environmental toxins, and now novel nicotine delivery systems. Co-authors Ashleigh R. Woollett and several early-career researchers—Natasha M. Dickie, Madison J. Kennedy, Jacob T. Liddle, Leila B.M. Nolan, and Megan Rawlins—from the same school contributed equally, highlighting UC's commitment to collaborative, interdisciplinary science.
This study builds on UC's prior vaping-related work, including cue reactivity and cessation strategies, reflecting the institution's proactive stance on student and public health issues. As a smoke-free and vape-free campus since 2011, UC enforces strict policies prohibiting smoking and vaping across all grounds, aligning research with practical campus wellness initiatives.
Methodology: A Qualitative Risk Assessment Approach
Rather than relying on long-term human epidemiology—which Professor Shaw notes could take 15 years due to cancer latency—the team conducted a qualitative risk assessment. They analyzed vape liquid components (propylene glycol, vegetable glycerin, nicotine, flavors) and their thermal decomposition at typical vaping temperatures (around 190°C).
Key steps included:
- Identifying aldehydes formed (formaldehyde, acrolein, acetaldehyde, propionaldehyde, methylglyoxal).
- Comparing concentrations in vape smoke to cigarette smoke using published data (e.g., mcg per puff).
- Assessing hazard via International Agency for Research on Cancer (IARC) classifications and animal studies (e.g., rat inhalation thresholds for tumors).
- Estimating human exposure: 90–150 mL puff volume, 4 sessions daily over years.
This hazard × exposure framework revealed vaping's carcinogenic potential without direct human trials.
Carcinogenic Chemicals in Vape Smoke: The Science Explained
When heated, vape liquids produce aldehydes—highly reactive compounds known for DNA damage and inflammation. Formaldehyde (IARC Group 1 carcinogen) levels in vape smoke match or exceed cigarettes, triggering nasal carcinomas in rats at concentrations vapers encounter. Acrolein (Group 2A) causes respiratory hyperplasia, a cancer precursor.
| Aldehyde | IARC Group | Vape Dose (mcg/puff) | Rat Trigger Conc. |
|---|---|---|---|
| Formaldehyde | 1 | 7.8 (up to 71) | 14.3 ppm |
| Acrolein | 2A | 0.012–19.2 | 2 ppm |
| Acetaldehyde | 2B | 0.02–22.5 | ~2700 mcg/L |
These induce genotoxic (DNA-altering) and non-genotoxic (inflammation-driven) carcinogenesis, with additive effects amplifying risks.
Key Findings: Lung and Oral Cancer Risks Confirmed
The study concludes: "Vaping is carcinogenic, but the risk is likely lower than for smoking cigarettes." Lung cancer risk arises from inflammation boosting cell division errors and direct DNA mutations. Oral risks stem from aerosol exposure in the mouth. No safe threshold exists; even low doses accumulate over time. Professor Shaw emphasized, "Chemicals produced... are definitely carcinogenic and they will very likely cause cancer in humans."
Photo by Phil Hearing on Unsplash
Vaping vs. Smoking: A Lesser but Real Danger
Aldehyde doses in vapes are comparable or lower than cigarettes, lacking polycyclic aromatic hydrocarbons like benzo[a]pyrene. Thus, vaping aids smoking cessation by reducing overall risk. However, for non-smokers—especially youth—it's an unnecessary addition: "Someone taking up vaping not as a tool for smoking cessation is adding carcinogenic risk."
Vaping Prevalence in New Zealand: Focus on Youth and University Students
New Zealand faces a vaping epidemic, with $401 million spent in 2025. Daily vaping: 11.7% adults (2024/25), 10.5% ages 15-17, 26.5% 18-24. University students show high ever-use (~38% in 2020 surveys), with Māori youth at 21.7% daily (Year 10). Rates are declining post-regulations, but campus hotspots persist.
NZ universities like UC enforce vape-free policies, but enforcement challenges remain amid rising student stress and social vaping.
Implications for New Zealand Higher Education Institutions
UC's study prompts unis to enhance health education. As vape-free campuses (e.g., UC, Auckland), policies ban devices everywhere, but support cessation programs. Rising student vaping links to mental health; unis must integrate toxicology insights into wellness, potentially via peer-led campaigns. For Māori/Pasifika students—disproportionately affected—culturally responsive interventions are key.UC Smoke-free Policy
Policy and Regulatory Context in Aotearoa
NZ's Smokefree 2025 goal faces hurdles from vaping. 2026 regs ban disposables, cap nicotine (20mg/mL), restrict flavors. Yet, youth access persists via loopholes. Experts like Andrew Waa (Otago) urge youth protections; Shaw calls for precaution. Unis advocate via ASPIRE Aotearoa.
- Prescription-only vapes proposed.
- Stricter retail compliance.
- Campus-wide cessation support.
Expert Perspectives and Broader Debate
Assoc. Prof. George Laking (Auckland): Valuable for relative risks; compare to daily exposures. Andrew Waa: Reinforces youth caution. VIANZ: Theoretical, not real-world risk. Balanced view: Supports quitting smoking, rejects recreational use.
Photo by Bayo Adegunloye on Unsplash
Future Research and UC's Ongoing Contributions
Longitudinal studies needed for quantification. UC's prior work on cessation (e.g., Joya Kemper) complements this. Potential: VR for cue reactivity, biomarkers in students. As NZ unis face enrollment strains, health research bolsters reputation.
Actionable Insights for Students, Staff, and Policymakers
- Students: Seek Quitline, campus counseling; avoid starting. - Staff: Promote evidence-based talks. - Policymakers: Fund uni research, tighten flavors/disposables. UC exemplifies higher ed's role in safeguarding futures.
This UC study, while alarming, offers clarity amid hype, reinforcing balanced harm reduction.Expert Reactions