Abstract
Recent increases in the popularity of affordable 3D printers necessitate research to investigate the potential volatile organic compound (VOC) exposure that an operator would experience. VOC emissions from a Formlabs Form 2 were tested using four different resins (Clear, White, Tough, and Elastic) across several time-resolved tests and exposure scenarios: an enclosed test chamber, and within a ventilated room at two distances, with an extraction hood to investigate "real-world" exposure scenarios and the impact of mitigation methods. 2-Hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, and 2-hydroxyethyl methacrylate were the prominent VOCs emitted from the resin 3D printing process, among other acrylic-based compounds. The composition of the VOCs was dependent on the type of resin: Elastic resin emitted a greater diversity of compounds, including the previously unreported isobornyl acrylate, while Tough resin emitted higher concentrations of smaller cross-linking compounds such as 2-hydroxyethyl methacrylate. VOC emissions peaked at the end of the active printing process when the build plate rose from the liquid resin bed. In the enclosed chamber scenario, total VOC (TVOC) concentrations exceeded 128,000 μg/m(3), representing worst-case poorly ventilated conditions. Under realistic room conditions, TVOC concentrations reached 45-116 μg/m(3) at 50 cm from the printer and returned to baseline within 2 h after printing ended. The TVOC emission concentrations were significantly reduced by 71-84% when the distance between the printer and the sampling position was increased from 0.5 to 2 m, or when an extraction hood fitted with a carbon VOC filter and particulate HEPA filter was used. These two exposure mitigation methods were considered practical options for home users, "maker" communities, and schools to use. While individual VOC concentrations remained well below established workplace exposure limits, many identified compounds lack published safety guidelines, making health risk assessment challenging, and both their acute and chronic health impacts remain unknown.