title: Estimation of the Human Extrathoracic Deposition Fraction of Inhaled Particles Using a Polyurethane Foam Collection Substrate in an IOM Sampler.
abstract: Extrathoracic deposition of inhaled particles (i.e., in the head and throat) is an important exposure route for many hazardous materials. Current best practices for exposure assessment of aerosols in the workplace involve particle size selective sampling methods based on particle penetration into the human respiratory tract (i.e., inhalable or respirable sampling). However, the International Organization for Standardization (ISO) has recently adopted particle deposition sampling conventions (ISO 13138), including conventions for extrathoracic (ET) deposition into the anterior nasal passage (ET₁) and the posterior nasal and oral passages (ET₂). For this study, polyurethane foam was used as a collection substrate inside an inhalable aerosol sampler to provide an estimate of extrathoracic particle deposition. Aerosols of fused aluminum oxide (five sizes, 4.9 µm-44.3 µm) were used as a test dust in a low speed (0.2 m/s) wind tunnel. Samplers were placed on a rotating mannequin inside the wind tunnel to simulate orientation-averaged personal sampling. Collection efficiency data for the foam insert matched well to the extrathoracic deposition convention for the particle sizes tested. The concept of using a foam insert to match a particle deposition sampling convention was explored in this study and shows promise for future use as a sampling device.
authors.affiliation: Rocky Mountain Center for Occupational & Environmental Health, Department of Family & Preventive Medicine, University of Utah, Salt Lake City, UT 84108, USA. darrah.sleeth@hsc.utah.edu.
authors.forename: Darrah K
authors.initials: DK
authors.lastname: Sleeth
authors.affiliation: Rocky Mountain Center for Occupational & Environmental Health, Department of Family & Preventive Medicine, University of Utah, Salt Lake City, UT 84108, USA. sbalthaser@gmail.com.
authors.forename: Susan A
authors.initials: SA
authors.lastname: Balthaser
authors.affiliation: Department of Pediatrics, University of Utah, Salt Lake City, UT 84108, USA. scott.collingwood@hsc.utah.edu.
authors.forename: Scott
authors.initials: S
authors.lastname: Collingwood
authors.affiliation: Rocky Mountain Center for Occupational & Environmental Health, Department of Family & Preventive Medicine, University of Utah, Salt Lake City, UT 84108, USA. rod.larson@hsc.utah.edu.
authors.forename: Rodney R
authors.initials: RR
authors.lastname: Larson
mesh_terms: D000336:Aerosols / Q000032:analysis* / Q000592:standards; D000395:Air Pollutants, Occupational / Q000032:analysis* / Q000592:standards; D004784:Environmental Monitoring / Q000379:methods* / Q000592:standards*; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis* / Q000592:standards; D008962:Models, Theoretical; D009055:Mouth / Q000503:physiopathology; D009296:Nasal Cavity / Q000503:physiopathology; D015969:National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division; D016273:Occupational Exposure / Q000032:analysis* / Q000592:standards; D010316:Particle Size; D011140:Polyurethanes / Q000032:analysis* / Q000592:standards; D013048:Specimen Handling / Q000379:methods; D014481:United States
chemical_list: D000336:Aerosols; D000395:Air Pollutants, Occupational; D011140:Polyurethanes; C028279:polyurethane foam
keywords: IOM sampler; extrathoracic deposition; inhalable particles; nasal passage; oral passage; polyurethane foam