Longitudinal Analysis of Airborne Microplastics and Cellulosic Fibers on a University Campus in Western Canada

Airborne cellulosic fibers (CFs) and microplastics (MPs) are emerging pollutants with potential environmental and health implications. This study presents an active sampling‐based characterization of airborne CFs and MPs in Western Canada, focusing on a university campus in Kelowna. Sampling was conducted from September 2021 to October 2022, on three separate days each month, using a BioSampler operated at 12.5 L/min, across one outdoor site and three indoor locations (cafeteria, gym laundry, and manufacturing shop). Outdoor environments exhibited higher concentrations of both total particles (CFs and MPs combined, 31.4 ± 46.9 particles/m 3 ) and MPs (5.67 ± 8.82 MPs/m 3 ) compared to indoor air (13.7 ± 12.1 particles/m 3 and 2.89 ± 4.72 MPs/m 3 ). CFs dominated total particle counts, while MPs were predominantly fragments and fibers, suggesting differential sources and fragmentation processes. Polymer identification using μ ‐FTIR spectroscopy revealed that polyester and polyamide were most prevalent across all locations, likely reflecting contributions from synthetic textiles and clothing, which are known sources of airborne MPs. Smaller contributions from other polymer types suggest the presence of additional location‐specific sources. Seasonal variations were also observed, with indoor MP concentrations peaking in summer, likely influenced by regional wildfires and the associated increase in indoor activities. Higher levels were additionally observed in winter at locations with increased fabric handling and material processing. These findings highlight the pervasive nature of airborne particles, even in smaller cities with localized sources. This study underscores the importance of targeted mitigation strategies and further research to understand the implications of chronic exposure to these pollutants on environmental and human health.