Atmospheric concentrations and deposition of polycyclic aromatic hydrocarbons to the Yellow Sea

Abstract

Atmospheric particle associated PAHs were monitored at the marine stations in Korea and in Tianjin and Qingdao, China during year 2003 to 2005. And on board samples were also collected during the cruise (2004 and 2005). Marine Station 1 (Baekryoung Island) and Station 2 (Jeju Island) is located at the western and southern part of Korea, respectively and has been operated since 2003. These stations were selected for monitoring the background concentration and long-range transported pollutants. China stations were Tianjin and Qingdao, well-known industrialized metropolitan cities neighboring the Yellow Sea. Particle phase PAHs were sampled using high volume air sampler. And during on-board sampling vapor phase PAHs were collected as well as particle associated PAHs using specially designed thimble-PUF (polyurethane foam) assembly for avoiding contamination and easy handling. Total PAHs in particulate phase were in the range of 0.18 ～ 23.2 ng/m3 with average of 4.67 ng/m3, and 0.24 ～ 14.7 ng/m3 with average of 3.43 ng/m3 in the marine Sts. 1 and 2, respectively. Winter season showed relatively elevated levels than other season, mainly due to the residential heating. Annual variations of dust were in the range of 0.02 ～ 0.33 mg/m3 and ten times higher concentration were observed in the Asian Dust period. There were no significant correlation between total PAHs and amount of dust. In Chinese cities, particle associated PAHs were in the range of 45.0 ～ 191 ng/m3 with average of 98.6 ng/m3, and 1.12 ～ 56.7 ng/m3 with average of 17.3 ng/m3 in the ambient air of Tianjin and Qingdao, respectively. PAH composition showed similar profiles regardless of sampling stations, implying similar emission sources. On-board sample showed that average vapor phase PAHs (3.62 ng/m3) were higher than average particulate PAHs (0.65 ng/m3). Dry deposition flux and gas transfer flux were calculated using average atmospheric particle phase, vapor phase and waterborne dissolved PAHs concen