Chemical characteristics and source apportionment of particulate matter (PM2.5) in Dammam, Saudi Arabia: Impact of dust storms

Atmospheric particulate matter (PM) is known to be harmful human and environmental health, with factors including particle size composition thought key drivers of toxicity. Understanding the hence sources PM critical distinguish between anthropogenic natural impacts, develop most efficient air pollution mitigation policies. This distinction particularly important in areas affected by dust storm activity from nearby arid regions, which may dominate long-term mass concentrations. In this work, 24-hour 2.5 samples were collected two locations Dammam city, Saudi Arabia during winter summer 2018, subjected detailed analysis assess characteristics sources. Offline chemical utilied ICP/MS, ion chromatography thermal decomposition for measurement trace metals, ions OC/EC concentrations, respectively. Positive Matrix Factorization (PMF) analyses used identify Dammam. The mean concentration was twice that at both locations, crustal secondary inorganic aerosol components dominated over other species determining concentrations seasons locations. PMF identified six source factors, crustal, nitrate-rich, sea salt, sulfate-rich, biomass burning traffic addition, impact storms on analysed. Dust increased average three-fold, elements five-fold while as origin limited. Overall, dust-storm accounted 42% concentration; after accounting aspect, derived largely primary pollutant emissions remaining mass. • Comprehensive assessment Dammam, Arabia. Average ranged 54 121 ug/m 3 . Dominant found elements, organic carbon. Anthropogenic 40% mass, rising 58% if periods excluded. These results highlight control priorities improve quality