Air-Water Exchange and Gas-Particle Partitioning of Polycyclic Aromatic Hydrocarbons (PAHs) in Coral Reef Areas of the South China Sea

In this study, we collected gas, particulate, and surface water-dissolved phase samples from 16 sites in the South China Sea from March 21 to April 12, 2018. Thereafter, all the samples were analyzed for the air-water exchange and source apportionment of polycyclic aromatic hydrocarbons (PAHs). Thus, it was observed that the overall PAH concentrations in the water and gas phases were 8.0 +/- 5.5 ng/L and 41.3 +/- 24.7 ng/m(3), respectively. Back trajectory simulation showed that the air masses in the South China Sea primarily originated from mainland China during the heating period, and air-water exchange analysis showed net deposition from air to water, with fluxes ranging from -5.53 to -89.72 ng/m(2)/d. Further, the logarithmic gas-particle partitioning coefficient (logK(p)) of the PAHs regressed linearly with the logarithmic subcooled liquid vapor pressure (log P0 L), with an average slope of -0.3 +/- 0.13.