Volatilization of polycyclic aromatic hydrocarbons (PAHs) over the North Pacific and adjacent Arctic Ocean: The impact of offshore oil drilling. (1st January 2021)

• Record Type: Journal Article
• Authors: Chen, Afeng; Wu, Xiaoguo; Simonich, Staci L. Massey; Kang, Hui; Xie, Zhouqing
• Is Part Of: Environmental pollution. Volume 268(2021)Part B
• Publication Date: 2021-01-01
• Subjects: PAHs -- Air-sea exchange -- Source identification -- The North Pacific and adjacent Arctic Ocean; 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.2020.115963
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Air and seawater samples were collected in 2016 over the North Pacific Ocean (NPO) and adjacent Arctic Ocean (AO), and Polycyclic Aromatic Hydrocarbons (PAHs) were quantified in them. Atmospheric concentrations of ∑15 PAHs (gas + particle phase) were 0.44–7.0 ng m −3 (mean = 2.3 ng m −3 ), and concentrations of aqueous ∑15 PAHs (dissolved phase) were 0.82–3.7 ng L −1 (mean = 1.9 ng L −1 ). Decreasing latitudinal trends were observed for atmospheric and aqueous PAHs. Results of diagnostic ratios suggested that gaseous and aqueous PAHs were most likely to be related to the pyrogenic and petrogenic sources, respectively. Three sources, volatilization, coal and fuel oil combustion, and biomass burning, were determined by the PMF model for gaseous PAHs, with percent contributions of 10%, 44%, and 46%, respectively. The 4- ring PAHs underwent net deposition during the cruise, while some 3- ring PAHs were strongly dominated by net volatilization, even in the high latitude Arctic region. Offshore oil/gas production activities might result in the sustained input of low molecular weight 3- ring PAHs to the survey region, and further lead to the volatilization of them. Compared to the gaseous exchange fluxes, fluxes of atmospheric dry deposition and gaseous degradation were negligible. According to the extrapolated results, the gaseous exchange of semivolatile aromatic-like compounds (SALCs) may have a significant influence on the carbon cycling in the low latitude oceans, but not for the high latitude oceans. Graphical abstract: Image 1 Highlights: PAHs were detected in air & sea water of the North Pacific and Arctic Ocean. Decreasing latitudinal trends were observed for atmospheric and aqueous PAHs. Some 3- ring PAHs were strongly dominated by net volatilization. Offshore oil drilling made for the input of 3- ring PAHs. Abstract : Offshore oil drilling in the North Pacific might result in the input of 3- ring PAHs to seawater and further led to the net volatilization of them from water to air.