After hearing @SamuraiSam 's comments in the Triton Oil System unpacking video regarding the safety of some of the wax pens out on the market, I thought it prudent to post the actual study behind his comments. The discussion on reddit is also linked in the Triton system post. I've only posted the Abstract of the study because the graphs will not load properly. To read the entire study, follow the link in the title.
Metal Concentrations in e-Cigarette Liquid and Aerosol Samples: The Contribution of Metallic Coils
Pablo Olmedo,1,2,3 Walter Goessler,4 Stefan Tanda,4 Maria Grau-Perez,1,2 Stephanie Jarmul,1 Angela Aherrera,1 Rui Chen,1 Markus Hilpert,2 Joanna E. Cohen,5,6 Ana Navas-Acien,1,2 and Ana M. Rule1
1Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA 2Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, New York, USA 3Department of Legal Medicine and Toxicology, School of Medicine, University of Granada, Granada, Spain
4Institute of Chemistry, University of Graz, Graz, Austria
5Department of Health, Behavior and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA 6Institute of Global Tobacco Control, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
BACKGROUND: Electronic cigarettes (e-cigarettes) generate an aerosol by heating a solution (e-liquid) with a metallic coil. Whether metals are trans- ferred from the coil to the aerosol is unknown.
OBJECTIVE: Our goal was to investigate the transfer of metals from the heating coil to the e-liquid in the e-cigarette tank and the generated aerosol.
METHODS: We sampled 56 e-cigarette devices from daily e-cigarette users and obtained samples from the refilling dispenser, aerosol, and remaining e-liquid in the tank. Aerosol liquid was collected via deposition of aerosol droplets in a series of conical pipette tips. Metals were reported as mass fractions (lg=kg) in liquids and converted to mass concentrations (mg=m3) for aerosols.
RESULTS: Median metal concentrations (lg=kg) were higher in samples from the aerosol and tank vs. the dispenser (all p < 0:001): 16.3 and 31.2 vs. 10.9 for Al; 8.38 and 55.4 vs. <0:5 for Cr; 68.4 and 233 vs. 2.03 for Ni; 14.8 and 40.2 vs. 0.476 for Pb; and 515 and 426 vs. 13.1 for Zn. Mn, Fe, Cu, Sb, and Sn were detectable in most samples. Cd was detected in 0.0, 30.4, and 55.1% of the dispenser, aerosol, and tank samples respectively. Arsenic was detected in 10.7% of dispenser samples (median 26:7 lg=kg) and these concentrations were similar in aerosol and tank samples. Aerosol mass concentrations (mg=m3) for the detected metals spanned several orders of magnitude and exceeded current health-based limits in close to 50% or more of the samples for Cr, Mn, Ni, and Pb.
CONCLUSIONS: Our findings indicate that e-cigarettes are a potential source of exposure to toxic metals (Cr, Ni, and Pb), and to metals that are toxic when inhaled (Mn and Zn). Markedly higher concentrations in the aerosol and tank samples versus the dispenser demonstrate that coil contact induced e-liquid contamination. https://doi.org/10.1289/EHP2175
Metal Concentrations in e-Cigarette Liquid and Aerosol Samples: The Contribution of Metallic Coils
Pablo Olmedo,1,2,3 Walter Goessler,4 Stefan Tanda,4 Maria Grau-Perez,1,2 Stephanie Jarmul,1 Angela Aherrera,1 Rui Chen,1 Markus Hilpert,2 Joanna E. Cohen,5,6 Ana Navas-Acien,1,2 and Ana M. Rule1
1Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA 2Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, New York, USA 3Department of Legal Medicine and Toxicology, School of Medicine, University of Granada, Granada, Spain
4Institute of Chemistry, University of Graz, Graz, Austria
5Department of Health, Behavior and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA 6Institute of Global Tobacco Control, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
BACKGROUND: Electronic cigarettes (e-cigarettes) generate an aerosol by heating a solution (e-liquid) with a metallic coil. Whether metals are trans- ferred from the coil to the aerosol is unknown.
OBJECTIVE: Our goal was to investigate the transfer of metals from the heating coil to the e-liquid in the e-cigarette tank and the generated aerosol.
METHODS: We sampled 56 e-cigarette devices from daily e-cigarette users and obtained samples from the refilling dispenser, aerosol, and remaining e-liquid in the tank. Aerosol liquid was collected via deposition of aerosol droplets in a series of conical pipette tips. Metals were reported as mass fractions (lg=kg) in liquids and converted to mass concentrations (mg=m3) for aerosols.
RESULTS: Median metal concentrations (lg=kg) were higher in samples from the aerosol and tank vs. the dispenser (all p < 0:001): 16.3 and 31.2 vs. 10.9 for Al; 8.38 and 55.4 vs. <0:5 for Cr; 68.4 and 233 vs. 2.03 for Ni; 14.8 and 40.2 vs. 0.476 for Pb; and 515 and 426 vs. 13.1 for Zn. Mn, Fe, Cu, Sb, and Sn were detectable in most samples. Cd was detected in 0.0, 30.4, and 55.1% of the dispenser, aerosol, and tank samples respectively. Arsenic was detected in 10.7% of dispenser samples (median 26:7 lg=kg) and these concentrations were similar in aerosol and tank samples. Aerosol mass concentrations (mg=m3) for the detected metals spanned several orders of magnitude and exceeded current health-based limits in close to 50% or more of the samples for Cr, Mn, Ni, and Pb.
CONCLUSIONS: Our findings indicate that e-cigarettes are a potential source of exposure to toxic metals (Cr, Ni, and Pb), and to metals that are toxic when inhaled (Mn and Zn). Markedly higher concentrations in the aerosol and tank samples versus the dispenser demonstrate that coil contact induced e-liquid contamination. https://doi.org/10.1289/EHP2175