ArticleScientific reports2019
High concentrations of flavor chemicals are present in electronic cigarette refill fluids.
Article in Scientific reports, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 103 papers, 2 of them syntheses that pooled it.
What it found
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
103 citing papers in PubMed, 2 syntheses or guidelines pooled it, 173 citations in OpenAlex.
- Pulmonary effects of e-liquid flavors: a systematic review.Journal of toxicology and environmental health. Part B, Critical reviews · 2022Pooled it
- Flavor-Toxicant Correlation in E-cigarettes: A Meta-Analysis.Chemical research in toxicology · 2020Pooled it
- Nanomolar vanillin, an e-cigarette flavorant, appears to disrupt pluripotency and promote endodermal differentiation in human embryonic stem cells via TRPV4 activation.Human reproduction (Oxford, England) · 2026Article
- Synthetic cooling agents enhance nicotine reinforcement and mesolimbic dopamine signaling.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2026Article
- Acute effects of electronic nicotine delivery system liquid nicotine form and sweet enhancer among people who use inhaled tobacco products.Experimental and clinical psychopharmacology · 2026Article
- Methylglyoxal and Glyoxal in High-Puff Disposable Electronic Cigarette Liquids: Unexpected Accumulation and Enhanced Cytotoxicity.ACS omega · 2026Article
- Influence of Cooling Agents on the Arrhythmogenic and Autonomic Effects of Electronic Cigarettes in an in vivo Model.Circulation. Arrhythmia and electrophysiology · 2026Article
- Water addition to e-liquids to reduce flavour aldehyde acetal formation: chemistry and user sensory experience and appeal.Tobacco control · 2026Article
- Effects of commercial unflavored and vanilla-flavored e-liquids on nicotine intake and withdrawal.bioRxiv : the preprint server for biology · 2026Article
- Analysing the acute toxicity of e-cigarette liquids and their vapour on human lung epithelial (A549) cellsToxicology reports · 2025Article
- Unraveling the Toxicological Effects of Hydroxyacetone - A Reaction Product in Electronic Cigarette Aerosols.bioRxiv : the preprint server for biology · 2025Article
- Article
- Stability of Flavoring Chemicals in e-Cigarette Liquids: A Naturalistic Product Aging Study over 24 months.ACS omega · 2025Article
- MMP12 deficiency attenuates menthol e-cigarette plus house dust-mite effects on pulmonary iron homeostasis and oxidative stress.Respiratory research · 2025Article
- The effects of flavored vaped e-liquids on cultured human macrophages derived from the central and peripheral nervous systems.Toxicology in vitro : an international journal published in association with BIBRA · 2025Article
- The influence of high-fat diet on nicotine vapor self-administration, neuronal excitability, and leptin levels in adult mice.Physiology & behavior · 2025Article
- Menthol, a consumer product additive, adversely affects human embryonic stem cells via activation of TRPM8 and TRPA1 channels.Stem cells translational medicine · 2025Article
- Acetaldehyde and methylglyoxal: comparative analysis of toxic electronic cigarette degradation products in 3D and 2D exposure systems using human bronchial epithelial models.Frontiers in toxicology · 2025Article
- Influence of electronic cigarette vapour on theBiomaterial investigations in dentistry · 2025Article
- Cannabis concentrate vaping chemistry.Frontiers in toxicology · 2025Review
43 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors at 2 institutions in 1 country.
Funding
Abstract
We characterized the flavor chemicals in a broad sample of commercially available electronic cigarette (EC) refill fluids that were purchased in four different countries. Flavor chemicals in 277 refill fluids were identified and quantified by gas chromatography-mass spectrometry, and two commonly used flavor chemicals were tested for cytotoxicity with the MTT assay using human lung fibroblasts and epithelial cells. About 85% of the refill fluids had total flavor concentrations >1 mg/ml, and 37% were >10 mg/ml (1% by weight). Of the 155 flavor chemicals identified in the 277 refill fluids, 50 were present at ≥1 mg/ml in at least one sample and 11 were ≥10 mg/ml in 54 of the refill fluids. Sixty-one% (170 out of 277) of the samples contained nicotine, and of these, 56% had a total flavor chemical/nicotine ratio >2. Four chemicals were present in 50% (menthol, triacetin, and cinnamaldehyde) to 80% (ethyl maltol) of the samples. Some products had concentrations of menthol ("Menthol Arctic") and ethyl maltol ("No. 64") that were 30 times (menthol) and 100 times (ethyl maltol) their cytotoxic concentration. One refill fluid contained cinnamaldehyde at ~34% (343 mg/ml), more than 100,000 times its cytotoxic level. High concentrations of some flavor chemicals in EC refill fluids are potentially harmful to users, and continued absence of any regulations regarding flavor chemicals in EC fluids will likely be detrimental to human health.
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What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.