Survey on the concentration and characterization of microplastics in the ambient air around the landfill and assessing the exposure of surrounding residents at different distances

Airborne microplastics are increasingly recognized as an emerging environmental concern. Most microplastic monitoring research has predominantly concentrated on aquatic or terrestrial environments. However, field-scale assessments near landfill facilities remain limited. This study presents a distance-based spatial and seasonal assessment of airborne microplastics around a municipal landfill and nearby residential areas. Active air sampling combined with microscopic analysis and Raman spectroscopy was used to characterize particles within the detectable size range of the applied method. The average concentration of microplastics ranges between a minimum of 0.2 MPs/m³ and a maximum of 2.8 MPs/m³. The detected microplastics varied in size from 17.38 to 479 μm, with particles smaller than 150 μm being the most prevalent. The predominant forms of microplastics found were fragments (67.5%) and fibers (30%). The majority of these particles consisted of polymers such as Polypropylene (32.5%), Polycarbonate (10%), Polyamide (17%), and Polyvinyl chloride(19.5%). Among all the detected colors, black, transparent, and gray were identified as the most preva lent in both seasons of the year. Furthermore, Microplastic inhalation rates are higher for individuals living within 5 km of a landfill compared to those beyond this distance. This study provides the first spatial and seasonal assessment of airborne microplastics around the Shiraz landfill. Also, Our study demonstrates the presence of airborne microplastics in the vicinity of a landfill and surrounding residential areas and provides preliminary insights into potential exposure scenarios, while acknowledging the limitations in conclusively attributing all detected particles to landfill-related sources. Although nano-sized plastics were not directly quantified, the observed size distribution suggests the possible presence of sub-micron plastic fractions below the analytical detection limit.