Han Minwei, Yu Kefu, Zhang Ruijie, Chen Biao, Li Haolan, Zhang Zheng-En, Li Jun, Zhang Gan
Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, Nanning 530004, China.
Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519080, China.
Environ Sci Technol. 2023 Dec 12;57(49):20750-20760. doi: 10.1021/acs.est.3c03452. Epub 2023 Nov 1.
The environmental implications of polycyclic aromatic hydrocarbons (PAHs) caused by the vigorous development of offshore oil exploitation and shipping on the marine ecosystem are unclear. In this study, the PAH concentrations were systematically characterized in multiple environmental media (i.e., atmosphere, rainwater, seawater, and deep-sea sediments) in the western South China Sea (WSCS) for the first time to determine whether PAH pollution increased. The average ∑PAHs (total concentration of 15 US EPA priority controlled PAHs excluding naphthalene) in the water of WSCS has increased and is higher than the majority of the oceans worldwide due to the synergistic influence of offshore oil extraction, shipping, and river input. The systematic model comparison confirms that the model can more accurately reflect the gas-particle partitioning of PAHs in the atmosphere of the WSCS. We also found that the vertical migration of the elevating PAHs is accelerated by particulate matter, driving the migration of atmospheric PAHs to the ocean through dry and wet deposition, with 16% being contributed by the particle phase. The particulate matter sinking alters the PAH distribution in the water column and generates variation in source apportionment, while the contribution of PAHs loaded on them (>20%) to the total PAH reserves cannot be ignored as before. Hence, the ecological threat of PAHs increases by the oil drilling and shipping industry, and the driving force of particulate matter deserves continuous attention.
海上石油开采和航运的蓬勃发展所导致的多环芳烃（PAHs）对海洋生态系统的环境影响尚不清楚。在本研究中，首次对南海西部（WSCS）多个环境介质（即大气、雨水、海水和深海沉积物）中的PAH浓度进行了系统表征，以确定PAH污染是否增加。由于海上石油开采、航运和河流输入的协同影响，WSCS水体中的平均∑PAHs（15种美国环保署优先控制的PAHs总浓度，不包括萘）有所增加，且高于全球大多数海洋。系统的模型比较证实，该模型能够更准确地反映PAHs在WSCS大气中的气-粒分配。我们还发现，上升的PAHs的垂直迁移因颗粒物而加速，通过干湿沉降推动大气PAHs向海洋迁移，其中16%由颗粒相贡献。颗粒物下沉改变了水柱中PAH的分布，并导致源解析产生变化，而附着在其上的PAHs对总PAH储量的贡献（>20%）已不能像以前那样被忽视。因此，石油钻探和航运业增加了PAHs的生态威胁，颗粒物的驱动作用值得持续关注。
