title: Identification of toxicants in cinnamon-flavored electronic cigarette refill fluids.
abstract: In a prior study on electronic cigarette (EC) refill fluids, Cinnamon Ceylon was the most cytotoxic of 36 products tested. The purpose of the current study was to determine if high cytotoxicity is a general feature of cinnamon-flavored EC refill fluids and to identify the toxicant(s) in Cinnamon Ceylon. Eight cinnamon-flavored refill fluids, which were screened using the MTT assay, varied in their cytotoxicity with most being cytotoxic. Human embryonic stem cells were generally more sensitive than human adult pulmonary fibroblasts. Most products were highly volatile and produced vapors that impaired survival of cells in adjacent wells. Cinnamaldehyde (CAD), 2-methoxycinnamaldehyde (2MOCA), dipropylene glycol, and vanillin were identified in the cinnamon-flavored refill fluids using gas chromatography–mass spectrometry and high-pressure liquid chromatography (HPLC). When authentic standards of each chemical were tested using the MTT assay, only CAD and 2MOCA were highly cytotoxic. The amount of each chemical in the refill fluids was quantified using HPLC, and cytotoxicity correlated with the amount of CAD/product. Duplicate bottles of the same product were similar, but varied in their concentrations of 2MOCA. These data show that the cinnamon flavorings in refill fluids are linked to cytotoxicity, which could adversely affect EC users.
authors: R Z
authors: RZ
authors: Behar
authors: B
authors: B
authors: Davis
authors: Y
authors: Y
authors: Wang
authors: V
authors: V
authors: Bahl
authors: S
authors: S
authors: Lin
authors: P
authors: P
authors: Talbot
mesh_terms: D000171:Acrolein / Q000031:analogs & derivatives / Q000737:chemistry / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D002935:Cinnamomum zeylanicum / Q000737:chemistry* / Q000633:toxicity*; D003627:Data Interpretation, Statistical; D004305:Dose-Response Relationship, Drug; D053595:Embryonic Stem Cells / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects; D005421:Flavoring Agents / Q000633:toxicity*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008168:Lung / Q000166:cytology / Q000187:drug effects; D058953:Neural Stem Cells / Q000187:drug effects; D013056:Spectrophotometry, Ultraviolet; D013778:Tetrazolium Salts; D013844:Thiazoles; D062789:Tobacco Products
chemical_list: D005421:Flavoring Agents; D013778:Tetrazolium Salts; D013844:Thiazoles; C017910:2-methoxycinnamaldehyde; D000171:Acrolein; C022616:thiazolyl blue; C012843:cinnamaldehyde