Ambient particulate matter in Saudi Arabia (1980–2025): spatiotemporal patterns, source dynamics, and strategic research priorities

Ambient particulate matter (PM) pollution poses a major environmental and public health challenge in arid regions, including Saudi Arabia. Natural dust storms and anthropogenic emissions interact in complex ways. This report synthesizes 167 peer–reviewed studies from the Scopus database focused on ambient PM in Saudi Arabia. Concentration levels, spatial and temporal patterns, and key research gaps were evaluated. The reviewed literature consistently shows that PM concentrations exceed the WHO guidelines for both PM_2.5 and PM₁₀. Most of the high concentrations were found in major urban centers, industrial areas, and pilgrimage-related activities. PM₁₀ levels are likely dominated by mineral dust and resuspension processes. PM_2.5 is likely to exhibit substantial contributions from anthropogenic sources, particularly traffic and industrial activities. Clear temporal variability was observed, particularly driven by seasonal meteorology. It was also affected by dust storms and short-term interventions such as the COVID-19 lockdown. The number of studies has increased every year; however, existing studies remain limited, with a heavy reliance on urban centers, short-term monitoring campaigns, and PM mass concentrations. Long-term ground-based observations, size-resolved measurements, chemical characterization, and human health analyses affected by PM remain scarce in this region. This review underscored the importance of integrating monitoring strategies that combine ground-based observation, reanalysis of satellite data, including machine learning. Smaller particles, such as UFPs, are also important for future studies, along with black carbon, sand and dust storms, and the chemical composition of PM, to support better air quality management and health risk assessment in Saudi Arabia.