Compositional and seasonal differences of gas and particle phase polycyclic aromatic hydrocarbons (PAHs) over the southern Baltic Sea coast

In this study, 16 USEPA-prioritized PAHs in gas- and particle-phase (PAH(g+p)), associated chemical and meteorological parameters, and backward trajectory simulations were explored in a coastal city in Poland, between April 2019 and May 2020. This study reports several important aspects of PAH(g+p), i.e. variation, composition, distribution profiles, impact of weather conditions, and correlation analysis between target PAH compounds and influencing inorganic gaseous pollutants. Specifically, higher and more variable concentrations of total PAH(g+p) (mean ± SD, ng m(−3)) were observed during winter (36.38 ± 24.19) compared to autumn (22.3 ± 17.44), summer (21.52 ± 13.30) and spring (19.90 ± 13.13). A distribution profile of parent PAH(g+p) was as follows: 3-ring > 4-ring > 2-ring > 5-ring > 6-ring, although their relative contribution to the total PAHs showed statistically significant differences between seasons (p < 0.05). Precipitation-driven loss of ΣPAH(g+p) was lower in the warm period than in the cold one, reflecting higher PAH concentrations in winter. A seasonal model-based analysis of incremental lifetime cancer risk showed a higher potential cancer risk for children than those for adult females and males. The adverse health impacts associated with PAH exposure via inhalation route indicate the need for implementation of pollution-control policies in this region.