Occurrence and gas/particle partitioning of PAHs in the atmosphere from the North Pacific to the Arctic Ocean

Gas- and particle-phase polycyclic aromatic hydrocarbons (PAHs) were collected in the atmosphere from the North Pacific to the Arctic Ocean to investigate their occurrence and gas/particle distribution. Significant linear correlations were observed between the gaseous concentrations of 9 PAHs and latitudes (r2 = 0.69). The regression of gaseous PAHs and 1/T also gave a certain extent correlation (r2 = 0.46). The gas/particle partition coefficients (KP) correlated well with the sub-cooled liquid vapor pressures (poL) of PAHs with slopes higher than the theoretical value of −1, and the regressions of logKP–logpoL possessed a general tendency to intersect at a point (−2.52, −1.60). The non-linear regression of logpoL and the particle fraction displayed a more significant correlation (r2 = 0.84) than the linear relation of logKP–logpoL (r2 = 0.69). The influence of soot on KP was investigated, and it was found that the predicted values derived from the soot-air model agreed relatively better with the field measurements than those calculated based on the Junge–Pankow model and the KOA-based model. The results indicated that soot played an important role on the partitioning of PAHs to aerosols, and the partitioning of PAHs is more sensitive to presence of elemental carbon compared to organic matter of the aerosol.