Atmospheric PCB Concentrations at Terra Nova Bay, Antarctica

Abstract

Concentrations of gas-phase polychlorobiphenyls (PCBs) were studied over an austral summer at a site in Terra Nova Bay, Antarctica. Gas-phase concentrations of individual PCB congeners in the atmosphere of Terra Nova Bay ranged from below the detection limit to 0.25 pg m(-3), with a mean concentration of sigmaPCB of 1.06 pg m(-3). The PCB profile was dominated by lower-chlorinated PCB congeners; in fact >78% of the total PCB content was due to congeners with 1-4 chlorine atoms and only about 10% with 5-7 chlorines, whereas higher-chlorinated PCB congeners were below detection limits. The mean sigmaPCB concentration obtained in this study were lower than those reported in previous Antarctic studies. Temporal concentration profiles of sigmaPCB do not correspond to seasonal temperature changes. In consideration of the low PCB concentrations observed, the studies with the wind roses, the regression between In P(PCB) and T(-1), and the distribution of congeners, we can hypothesize that PCB local source contributions are not very important, whereas long-distance transport is the prevalent factor bringing PCBs to Terra Nova Bay.

Remote Zones Air Quality. Persistent Organic Pollutants: Sources, Sampling and Analysis

“…Over 90% of the total PCB content was due to congener with one to four chlorine atoms and only about 10% with five to seven chlorines, whereas higher chlorinated PCBs were below detection limits. In agreement with other studies, the results emphasized that the PCB profile was dominated by tri-CB and tetra-CB with relatively high contributions from mono-CB and di-CB (Gambaro et al, 2005). In addition, investigations on POP distribution in Antarctica were made by Ockenden at al.…”

“…For POP determination, the PUF is Soxhelt-extracted with organic solvents for several hours. After concentration and clean-up, the extracts are analysed by gas chromatography-mass spectrometry (GC-MS) (Gambaro et al, 2005;Kallenborn et al, 1998) or by gas chromatography-electron capture detection (GC-ECD) (Montone et al, 2003). In order to minimize the interfering substances contamination and to provide acceptable blanks, prior the sampling the PUF plugs have to be cleaned by a long Soxhlet extraction, then the cleaned PUF plugs are dried in a dessicator, packed in glass flasks and sealed in plastic bags until sampling (Montone et al, 2003).…”

“…Atmospheric levels of PCBs were correlated with meteorological conditions (as well as to the general synoptic atmospheric circulation of the region) and the higher levels were associated with the passage of the frontal system coming from South America over the Drake Passage causing a local increase in air temperature and surface winds from northwest, north and northeast (Montone et al, 2003). Gambaro et al (2005) monitored the air near Italian Antarctic Research Station. Gas-phase concentration of individual PCB congeners in the air of Terra Nova Bay ranged from below detection limit 0.25 pg m -3 .…”

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

“…The fate, transport and sinks of PCBs in different global regions and environments have received considerable attention during the last decades (see for example Lohmann et al, 2007). The occurrence of PCBs have also been reported in remote regions such as Antarctica and the Southern Ocean atmosphere (Tanabe et al, 1983;Iwata et al, 1993;Kallenborn et al, 1998;Fuoco et al, 1996;Montone et al, 2003Montone et al, , 2005Gambaro et al, 2005), seawater (Tanabe et al, 1983;Galbán-Malagón et al, 2013), soils (Cabrerizo et al, 2012;Kang et al, 2012) and biota (Larsson et al, 1992;BengtsonNash et al, 2008;Galbán-Malagón et al, 2013a;Cabrerizo et al, 2012;Zhang et al, 2013;Brault et al, 2013). The atmospheric long-range transport of PCBs occurs through successive steps of volatilization and deposition (hops) and PCBs can reach eventually Polar Regions like the Arctic and Antarctica (Wania and Mackay, 1996;Jurado and Dachs, 2008).…”

“…Also, the direct transport of PCBs from South America was evidenced by temporal series at Signy island (Kallenborn et al, 1998). However, the previous studies on the atmospheric occurrence of PCBs in Antarctica covered small geographic areas and most were restricted to sites near Antarctic scientific bases (Larsson et al, 1992;Kallenborn et al, 1998;Ockenden et al, 2001;Gambaro et al, 2005;Baek et al, 2011;Li et al, 2012;Cabrerizo et al, 2013;Kallenborn et al, 2013). In the present study, we report the atmospheric gas and aerosol phase PCBs occurrence from samples taken during three Antarctic cruises (2005, 2008 and 2009) covering a large region including the Bransfield Strait and the Weddell, Bellingshausen and South Scotia Seas.…”