Abstract:
The presence of polycyclic aromatic hydrocarbons (PAHs) in urban areas due to human activities poses a significant risk to human health. A comparative study of three representative sites (AUB, BCD, and NSMU) in Beirut revealed varying levels of PAHs and PM2.5, with AUB showing the lowest concentrations. The demand for electricity, particularly during the hot summer season, and stagnant weather conditions contribute to high concentration of PAHs, in summer as well as in winter and fall. The study also found that the cancer risk associated with PAH exposure exceeded acceptable thresholds set by the Environmental Protection Agency (EPA), in the three sites, emphasizing the need for effective emission regulations. Additionally, source apportionment analysis identified diesel generators, incinerators, and gasoline/vehicular emissions as significant contributors to PAH pollution. Diesel generators played a prominent role in high socio- economic areas (BCD), while vehicular and traffic emissions were more influencing in low-to-middle income areas (NSMU).These findings demonstrate the need for targeted mitigation strategies to reduce PAH emissions and improve air quality in urban environments.