Comparative Assessment of PM2.5-Bound PAHs in Two Port Areas: Preliminary Identification of Possible Sources and Health Risk Analysis

Particulate matter is a significant component of air pollutants, especially PM2.5-bound polycyclic aromatic hydrocarbons (PAHs), due to multiple toxicological effects on organisms. In this study, the concentrations of PM2.5-bound PAHs at the two most important ports in Mexico (Veracruz and Manzanillo) were determined to identify emission sources and evaluate potential health impacts. Average PM2.5 concentrations were higher in Veracruz (12.90 ± 4.77 μg/m3) than in Manzanillo (10.96 ± 3.99 μg/m3), although both were below Mexico’s current air quality standards. Total PAH concentrations were also higher in Veracruz (22.14 ± 16.76 ng/m3) compared to Manzanillo (11.65 ± 9.04 ng/m3). The identified PAHs and diagnostic ratios indicated different emissions patterns: in Manzanillo, concentrations were associated with high-temperature pyrogenic sources, while in Veracruz, greater contributions from mixed sources were observed. The ILCR assessment was 4.61 × 10−7 for Manzanillo and 8.77 × 10−7 for Veracruz, both below the accepted risk threshold. Despite relatively low health risk estimates, the presence of carcinogenic PAHs, such as benzo[a]pyrene, highlights the need for continuous monitoring and mitigation strategies in port environments. These results provide pioneering, highly valuable insights into the dynamics of air pollution in these Mexican ports and their potential health implications.