Real-Time Source Apportionment with ACSM-Xact-Aethalometer (AXA) and SoFi RT

Particulate matter (PM) air pollution poses a significant threat to public health and the environment, particularly in urban areas. To mitigate these impacts, understanding the sources of PM through accurate source apportionment (SA) is essential for informed air quality management. Traditional SA methods rely on offline data collection, which delays responses to pollution events. However, advancements in monitoring technology have made real-time SA possible, providing continuous and detailed insights into pollution contributors. This study introduces the first deployment of the ACSM-Xact-Aethalometer (AXA) system combined with SoFi RT software for real-time PM source apportionment (RT-SA) in Athens, Greece.

The AXA system integrates chemical, elemental, and black carbon data, offering a holistic view of PM sources in an urban context. The analysis identified traffic emissions as the largest PM contributors, while secondary components, such as organic aerosols, sulfate, nitrate, and ammonium, accounted for for over 50% of the total PM mass. Primary emissions from sources like biomass burning and cooking contributed around 10% each, while natural sources such as sea salt and dust made up the remainder. By capturing organic, elemental, and black carbon fractions, the AXA setup provides a comprehensive profile of PM composition.

The use of SoFi RT software enables continuous, near-instant SA with automated data analysis, enhancing the identification of pollution sources in real time. The findings demonstrate the system’s capability to accurately detect key PM contributors and highlight its potential to revolutionize urban air quality monitoring, paving the way for targeted interventions to reduce PM pollution.