Airborne microplastics pollution in municipal solid waste processing and disposal complex: Concentration, characterization, and composition

Processing and disposal facilities of municipal solid waste play a significant role in emitting pollutants. We designed this study to investigate one of the emerging environmental pollutants, airborne microplastics (MPs), in the air samples collected from various locations (pre-processing hall, office building, windrow composting area, compost refinery plant, landfill sites, incineration plant, and background) of the largest municipal solid waste processing and disposal complex (MSWPDC) in Iran. We employed a qualitative and quantitative approach using a stereo microscope and micro Raman spectroscopy to analyze the airborne MPs feature. Airborne MPs concentration ranged from 1.7 and 24.7 N/m 3 with an average (± standard deviation( of 6.54 ± 5.08 N/m 3 . The highest concentrations were found in the windrow composting area, with an average concentration of 12.4 ± 9.32 N/m 3 . Given morphologies, fibers exhibited the highest proportion, making up approximately 64% of the total. All airborne MPs had a size range between 5 and 2984 μm, mainly in the range of 100 to 500 μm. Regarding composition and color, PET/Polyester and transparent were the dominant, accounting for 26% and 32% of the total, respectively. Our findings showed a high concentration of MPs in the air of the Aradkooh MSWPDC. The findings underscore the importance of implementing stronger measures to reduce MPs emissions, as AMSWPDC could be a potential source of MPs pollution in the surrounding areas.