Vaping cartridge heating element compositions and evidence of high temperatures

Abstract

Background Identifying the functional materials inside vaping devices can help inform efforts to understand risk. While nicotine E-cigarette components and metals have been characterized in several previous studies, the internal component compositions of tetrahydrocannabinol (THC) cartridge designs are not as well known. The 2019-20 e-cigarette or vaping product use associated lung injury (EVALI) outbreak has been associated with THC devices containing vitamin E acetate (VEA), possibly mediated by chemical reactions with internal cartridge components and high filament temperatures. Methods We investigate the composition and internal components of 2019 EVALI patient-associated THC vaping devices compared to other THC and nicotine devices from 2016-19, specifically the metal, ceramic, and polymer components likely to be exposed to heat. To do this, we have disassembled forty-eight components from eight used and unused vaping devices under a microscope and analyzed them using X-ray fluorescence, scanning electron microscopy, and Fourier-transform infrared micro-spectroscopy. Conclusions The two THC cartridges used by EVALI patients exhibited evidence of localized high temperatures, including charring of the ceramic heating elements and damaged wire surfaces. The newer THC cartridges possessed more ceramic and polymer insulation than older THC or nicotine devices. The combination of ceramics, metals, and high temperatures in newer THC cartridges is consistent with conditions hypothesized to produce VEA reactions during vaping. Nickel and chromium components were detected in all devices, and others contained copper, lead, tin, gold, silicon-rich rubbers, or fluorinated microplastics. These components have the potential to thermally degrade and volatilize if heated sufficiently. These

Design features and elemental/metal analysis of the atomizers in pod-style electronic cigarettes

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Analysis of Toxic Metals in Aerosols from Devices Associated with Electronic Cigarette, or Vaping, Product Use Associated Lung Injury

“…This ceramic heating element may provide more surface area for aerosol production from the more viscous liquids used in cannabinoid-based devices [ 24 ]. Cannabinoid-based EVP devices also contain a heating element and connectors, but they are more insulated from the liquid by the ceramic fiber wicking [ 25 ]. The design of the nicotine-based EVPs often consists of a silica wick which can absorb the less viscous propylene glycol and glycerol solvents.…”

Major Constituents of Cannabis Vape Oil Liquid, Vapor and Aerosol in California Vape Oil Cartridge Samples

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