Factors affecting the atmospheric occurrence and deposition of polychlorinated biphenyls in the Southern Ocean

Abstract

Abstract. Persistent organic pollutants, such as polychlorinated biphenyls, reach the Southern Ocean atmosphere through long-range atmospheric transport. In this study we report the largest dataset available for the atmospheric occurrence of PCBs in the Southern Ocean surrounding the Antarctic Peninsula from samples obtained during three cruises in 2005, 2008 and 2009. The gas phase concentrations of total PCBs ( 25 PCBs) ranged from 1 to 70 pg m −3 , while the aerosol phase concentrations were significantly lower (0.04 to 0.4 pg m −3 ). The aerosol phase is enriched in the more hydrophobic congeners consistent with the model predictions of gas-particle partitioning. There is a net airto-water diffusive flux of PCBs to the Southern Ocean, up to 100 times higher than the dry deposition flux of aerosolbound PCBs. The air-water disequilibrium is higher for the more hydrophobic congeners consistent with the role of the biological pump removing PCBs from the water column by settling of PCBs bound to organic matter. The atmospheric half-lives of PCB 52 and 180 are of 3.8 and 1 days, respectively, as calculated from the measured atmospheric concentration and depositional fluxes. The volatilization of PCBs from Antarctic soils during the austral summer drives higher gas phase concentrations in the atmosphere over Antarctica during the warmer periods. This temperature dependence is not observed for PCBs over the adjacent Southern Ocean, probably due to the importance of long-range atmospheric transport and atmospheric deposition modulating the atmospheric occurrence of PCBs.

A Global 3‐D Ocean Model for PCBs: Benchmark Compounds for Understanding the Impacts of Global Change on Neutral Persistent Organic Pollutants

“…Organic carbon remineralization rates are used as a proxy for bacterial activity in the water column (Dutkiewicz et al, ; Y. Zhang et al, ). Resulting modeled degradation half‐lives in the upper ocean (top 1,000 m) for CB‐28 (3.8 years), CB‐101 (10.4 years), CB‐153 (20.9 years), and CB‐180 (27.2 years) agree well with those reported elsewhere (Galbán‐Malagón, Del Vento, Cabrerizo, et al, ; Sinkkonen & Paasivirta, ; Wania & Daly, ).…”

Concentration and sources of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in surface soil near a municipal solid waste (MSW) landfill

“…Compounds from the PCB group are transported in the adsorbed form on dust particles. The behaviour of PCBs released into the air is influenced by numerous factors, such as ambient temperature, vapour pressure, and concentrations of total suspended particles (TSP) (Galbán-Malagón et al, 2013), a wet and dry deposition and long-range atmospheric transport depend on the partitioning factor between gas and particle phases (Mandalakis and Stephanou, 2007). The similarity in terms of the composition of the SS2, SS3, SS4, SS8 and SS9 samples may result from meteorological conditions, i.e.…”

Sources and fate of polycyclic aromatic hydrocarbons in the Antarctic and Southern Ocean atmosphere

“…However, despite the multiple potential sources of PAHs to the Antarctic environment, most of the previous studies on organic pollutants have focused on quantifying the presence of legacy POPs, such as PCBs or OCPs, in the various Antarctic compartments [Cabrerizo et al, 2013;Li et al, 2012;Baek et al, 2011;Galbán-Malagón et al, 2013a], while there is a lack of information regarding the presence, transport pathways, and sources of PAHs in the Antarctic atmosphere despite its importance as a primary vector for the introduction of PAHs to remote areas.…”

“…All samples were soxhlet extracted during 24 h after adding the surrogate standards and further analyzed. Details of the extraction and fractionation scheme for both the high-volume samples, aerosol phases, and surface and air fugacity samples can be found elsewhere [Cabrerizo et al, 2009[Cabrerizo et al, , 2011cGalbán-Malagón et al, 2013a, 2013b. All samples were analyzed for the following PAHs: phenanthrene (Phe), anthracene (Ant), fluoranthrene (Flu), pyrene (Pyr), benzo (a)anthracene (B(a)ant), chrysene (Cry), benzo(b&k)fluoranthene (B(b&k)f), benzo(e)pyrene (B(e)pyr), benzo(a) pyrene (B(a)pyr), perylene (Pery), dibenzo(a,h)anthracene (Dib(a,h)ant), benzo(g,h,i)perylene (B(g,h,i)pery), indeno(1,2,3-cd)pyrene (In(1,2,3-cd)pyr, dibenzonthiophene (DBT), methyldibenzonthiophenes (ΣMDBT), methylphenanthrenes (ΣMP), and dimethylphenanthrenes (ΣDMPD).…”

“…Dachs (2014), Sources and fate of polycyclic aromatic hydrocarbons in the Antarctic and Southern Ocean atmosphere, Global Biogeochem. Cycles, 28, 1424-1436, doi:10.1002 to research stations [Cabrerizo et al, 2012;Aislabie et al, 1999;Mazzera et al, 1999], (ii) emissions from research and tourist vessels and accidental spills of fuel, (iii) secondary sources due to volatilization from soils and snow as recently demonstrated for persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) [Cabrerizo et al, 2013;Galbán-Malagón et al, 2013a, 2013b, and (iv) natural sources of PAHs in Antarctica due to natural losses or seeps of petroleum or coal deposits, meteorites, and biogenic production in soils, sediments, and the water column [Botta et al, 2008;Clemett et al, 1998;Naraoka et al, 2000;Wilcke, 2007;Cabrerizo et al, 2012]. This biogenic production could be related to the degradation of diterpenes from the organic matter pool.…”