Net volatilization of PAHs from the North Pacific to the Arctic Ocean observed by passive sampling. (1st May 2021)

• Record Type: Journal Article
• Authors: Zheng, Haowen; Cai, Minggang; Zhao, Wenlu; Khairy, Mohammed; Chen, Mian; Deng, Hengxiang; Lohmann, Rainer
• Is Part Of: Environmental pollution. Volume 276(2021)
• Publication Date: 2021-05-01
• Subjects: Polycyclic aromatic hydrocarbons -- Low-density polyethylene -- Air-sea exchange -- Long-range transport -- High-latitude marine environment; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2021.116728
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: The North Pacific-Arctic Oceans are important compartments for semi-volatile organic compounds' (SVOCs) global marine inventory, but whether they act as a "source" or "sink" remains controversial. To study the air-sea exchange and fate of SVOCs during their poleward long-range transport, low-altitude atmosphere and surface seawater were measured for polycyclic aromatic hydrocarbons (PAHs) by passive sampling from July to September in 2014. Gaseous PAH concentrations (0.67–13 ng m −3 ) were dominated by phenanthrene (Phe) and fluorene (Flu), which displayed an inverse correlation with latitude, as well as a significant linear relationship with partial pressure and inverse temperature. Concentrations of PAHs in seawater (1.8–16 ng L −1 ) showed regional characteristics, with higher levels near the East Asia and lower values in the Bering Strait. The potential impact from the East Asian monsoon was suggested for gaseous PAHs, which – similar to PAHs in surface seawater - were derived from combustion sources. In addition, the data implied net volatilization of PAHs from seawater into the air along the entire cruise; fluxes displayed a similar pattern to regional and monthly distribution of PAHs in seawater. Our results further emphasized that air-sea exchange is an important process for PAHs in the open marine environments. Graphical abstract: Image 1 Highlights: Phe and Flu dominated the PAH concentrations from the Pacific to the Arctic. Combustion sources and the potential impact from the monsoon affected PAHs. The PAHs volatilization fluxes varied significantly both regionally and monthly. Diffuse fluxes contribute greatly to the air-sea exchange of PAHs in open oceans.