57
(Bohlin-58
Nizzetto et al., 2021). The annual means of SCCPs were comparable from 2013 to 2020, while MCCPs showed increasing trends. In the Antarctic, the average concentration of SCCPs in air has increased by nearly two orders of magnitude in recent years, from 15 to 1200 pg/m3, while the average concentration of MCCPs has changed little, from 4.5 to 5.1 pg/m3 (Figure 9 and Table 11) (Jiang et al., 2021; Ma et al., 2014). Ma et al. collected atmospheric gas phase and particle phase samples on King George Island, Antarctic, and systematically studied the content level,
homologous distribution characteristics, pollution sources and gas/solid distribution behavior of CPs in the Antarctic atmosphere. SCCPs were measured in all atmospheric samples in Antarctic, especially in the atmospheric particle and gas phases at King George Island, Antarctic. The concentration of SCCPs ranged from 9.6 to 21 pg/m3, with an average of 15 pg/m3.
Through two regression models (the Junge–Pankow model and the KOA-based model), Ma et al.
also found that the absorption mode of organic matter by aerosols played an important role in the distribution and migration of CPs in the atmosphere in remote areas of Antarctic (Ma et al., 2014). Lu et al. further established three different models (the J–P model, H–B model, and L–M–Y model) to estimate and measure the gas/particle distribution process of local CPs. It was found that the steady-state model (J–P model) rather than the equilibrium state models (J–P model and H–B model) better represented the gas/particle distribution process of CPs in Antarctic, which provides some help for the long-term study of CP concentration levels (Jiang et al., 2021).
Table 11: Occurrence of SCCPs in air (pg/m3) in the Antarctic
Location Sampling Time Sample Number Range Mean
King George Island,
Antarctic 2014-2018 120 70-4200 1200
King George Island,
Antarctic 2013 24 9.6-21 15
Source: Jiang et al. 2021, Ma et al. 2014.
6.3.2 SCCPs in soil
As an environmental matrix, soil is the basis of terrestrial ecosystems. Environmental pollutants can enter and accumulate in high trophic organisms through the chain of soil-plant-herbivore-carnivore, and this is especially true for persistent organic pollutants that have lipophilic and biomagnification characteristics, such as SCCPs. The source of SCCPs in the soil in Antarctic and the Arctic is not a direct emission source; rather, it is mainly the material exchange between the soil and atmosphere. The average concentrations of SCCPs in Antarctic and Arctic soils were 14.8 and 7.1 ng/g, respectively, which proved the extensive occurrence of SCCPs in polar soils (Table 12) (Li et al., 2016, Li et al., 2017).
Table 12: Concentrations of SCCPs (ng/g) in soil in the Arctic and the Antarctic
Location Sampling Time Sample Number Mean Concentration
King George Island and
Ardley Island, Antarctic 2012-2013 8 15
Ny-Ålesund, Arctic 2011-2012 7 7.1
Source: Li et al. 2016, Li et al. 2017.
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Figure 8: Annual mean concentrations of SSCCP and SMCCP (pg/m3) in air samples at Zeppelin (Svalbard, Norway), 2013-2020
Source: Bohlin-Nizzetto et al. 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021.
Figure 9: Annual mean concentrations of SCCPs and MCCPs (pg/m3) in air samples at the Great Wall Station (Georgia King Island, Fildes Peninsula of Antarctic), 2013-2018
Source: Jiang et al. 2021, Ma et al. 2014.
2013 2014 2015 2016 2017 2018
0 500 1000 1500 2000 2500
∑SCCPs ∑MCCPs
Concentration (pg/m3 )
0 20 40 60 80 100
Concentration (pg/m3 )
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Table 13: Concentrations of SCCPs (ng/g) in organism in the Arctic and the Antarctic
Location Sampling Time Tissue Range Mean Note
King George and Ardley Island 2012-2013 Archeogastropoda 120 dw
King George and Ardley Island 2012-2013 Neogastropoda 89 dw
King George and Ardley Island 2012-2013 Fish 70 dw
King George and Ardley Island 2012-2013 Algae 61 dw
King George and Ardley Island 2012-2013 Moss 42 dw
Southern Ocean 2007-2015 Whales Blubber <MDL-46 lw
Hudson Bay Canada 2013-2014 polar bears liver 120-250 170 lw
Greenland 2012 Black guillemot eggs 490-940 710 ww
Greenland 2012 Glaucous gull liver 170-390 230 ww
Greenland 2014 Glaucous gull liver 170-270 220 ww
East Greenland 2012 Ringed seal blubber 910-1900 1400 ww
Greenland 2014 Ringed seal blubber 710-1200 940 ww
West Greenland 2014 Ringed seal blubber 560-1400 880 ww
Greenland 2012 Polar bear tissue 1200-2700 2200 ww
Greenland 2014 Polar bear tissue 370-1600 880 ww
Ny-Ålesund, Arctic 2011-2012 Brown algae 81 dw
Ny-Ålesund, Arctic 2011-2012 Gammarids 520 dw
Ny-Ålesund, Arctic 2011-2012 Cod 210 dw
Ny-Ålesund, Arctic 2011-2012 Moss 210 dw
Ny-Ålesund, Arctic 2011-2012 Sooty sedge 330 dw
Ny-Ålesund, Arctic 2011-2012 Arctic bell-heather 180 dw
Ny-Ålesund, Arctic 2011-2012 Mountain avens 140 dw
Sklinna and Røst island 2012-2012 Bird egg <MDL-4.8 ww
waters around Iceland 2001-2003 Greenland sharks liver <MDL-5200 lw
Bear Island and Iceland 2001-2004 Liver of fish and seabird 5-88 ww
Revingehed, SkAne 1986 Rabbit muscle 2900 lw
Grimso, Vastmanland 1985-1986 Moose muscle 4400 lw
Ottsjo, Jamtland 1986 Reindeer suet 140 lw
Lake Storvindeln, Lapland 1986 Whitefish muscle 1000 lw
Kongsfjorden, Svalbard 1981 Ringed seal blubber 130 lw
MDL: Method detection limit; dw: dry weight; lw: lipid weight; ww: wet weight
Source: Li et al. 2016, Casa et al. 2019, Letcher et al. 2018, Vorkamp et al. 2017, Li et al. 2017, Huber et al. 2015, Strid et al.
2013, Reth et al. 2006, Jansson et al. 1993.
61 6.3.3 SCCPs in biota
Biological absorption of SCCPs in the environment and continuous enrichment of these pollutants in the body lead to the detection of high concentrations of SCCPs. (Casa et al., 2019;
Huber et al., 2015; Letcher et al., 2018; Strid et al., 2013; Vorkamp et al., 2017). The SCCP content in environmental samples from King George Island and Ardley Island in Antarctic ranged from 3.5 to 257 ng/g, and the average concentration was 76.6 ng/g (Table 13) (Li et al., 2016). The concentration of SCCPs in the ecosystem of the Svalbard Islands in the Arctic ranged from 6.0 to 611 ng/g dw, with an average value of 165 ng/g. Among them, the concentration level of SCCPs in aquatic species was slightly higher than that in terrestrial plant samples (Li et al., 2017). The content level of SCCPs in polar regions was relatively low. Li et al. further studied the long-distance transport mechanism of SCCPs through the composition characteristics of SCCPs in the Antarctic and Arctic. The chlorinated congeners in the Antarctic and Arctic samples were mainly Cl6 congeners, accounting for 38.0% and 34.8% of the total content of SCCPs, respectively. In terms of carbon chain length, short carbon chain (< C10) congeners accounted for the main components in Antarctic and Arctic samples, accounting for 56.1% and 48.6% of the total SCCPs, respectively (Li et al., 2016; Li et al., 2017), which was consistent with the pollution
characteristics of SCCPs in Arctic marine mammals (Tomy et al., 1999). Reth et al. also found that C10 congeners of SCCPs detected in biota in the North Sea were more abundant than those in the Baltic Sea. (Reth et al., 2006)
6.3.4 Environmental pathways
The fractionation of short carbon chain congeners occurred in the environmental samples of the North and South Poles compared with the environmental samples of middle and low latitudes and industrial products. This difference is mainly because short carbon chain congeners have higher volatility than do long carbon chain congeners, and they are more likely to travel over long distances with the atmosphere. C10 congeners have a lower Kow and a higher water solubility than that of other long carbon chain congeners, and they do easily adsorb and settle on water particles, so it is easier for them to migrate globally with the ocean current. The enrichment of short carbon chain and low chlorinated congeners in polar and polar environmental samples is the specific embodiment of the physicochemical properties of different congeners of SCCPs (Tomy et al., 2000).
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