AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Lung Dosimetry Assessments of Welding Fume and Gas Exposure using a Virtual Human Model with a Subject-Specific Respiratory System
JIANAN ZHAO, Yu Feng, Macrio Bezerra, Jun Wang, Ted Sperry, Oklahoma State University
Abstract Number: 29 Working Group: Indoor Aerosols
Abstract Welders are constantly exposed to airborne fumes and gases. Exposures to metallic particles and toxic gases generated by welding can lead to respiratory diseases, neurological ailments, and ultimately cancer. Hazard identification and risk assessment are necessary for constructing a health-friendly welding environment. Accurate information on the transport and deposition of metal aerosols in the respiratory system and skin absorption are critically needed for precise health risk assessments. However, measurements from human and animal studies are restricted by the limitations of imaging resolutions and operational flexibilities. To overcome the drawbacks of conventional investigation methods, the experimentally validated computational fluid-particle dynamics (CFPD) models can be the alternatives, which are capable of providing local lung deposition distributions based on the natural laws of physics in a noninvasive manner. In this study, a multiscale CFPD model was developed and applied to a virtual fabrication shop integrated with a virtual human in order to evaluate the effects of ventilation conditions, particle size, and gas species on lung uptake and skin absorption, as well as ambient distribution and deposition. Numerical results indicate that the ventilation condition can significantly influence welding gas transport and deposition. Besides, the air-tissue absorption coefficient is the key factor in pulmonary gas absorption. For metallic particles with diameters 100, 190, and 830 nm, total particle deposition fractions were less than 18.0%, and most of them deposited in the oral cavity. Furthermore, particles tend to penetrate to the two upper lobes more than the rest three lobes.In summary, a validated in silico investigative framework has been built. Welding particle and gases transmission, transport, and deposition have been simulated and analyzed from the emission source to the human respiratory system. This work paves the way to build a personalized virtual human and indoor environment for noninvasive precise health risk assessments.