Sources and composition of chemical pollution in Maritime Antarctica (King George Island), part 1: Sediment and water analysis for PAH sources evaluation in the vicinity of Arctowski station.

The paper presents a study regarding the identification of polycyclic aromatic hydrocarbons (PAHs) in fresh waters and surface sediments on the western shore of Admiralty Bay over four sampling seasons from 2017 to 2018. The results were compared to literature data from 2016 to provide a more comprehensive image of the environmental fate of PAHs over the years. The highest value of Σ PAHs was 82.9 ng/L and 445 ng/g dw in water and sediment samples, respectively. The analysis of PAH indicator ratio values showed that pyrogenic or mixed sources contribute to the PAH pollution in Antarctic sediments and water more than does petroleum. The main source is the combustion of biomass (e.g. as a result of fires) and coal, and PAHs are mostly associated with the activity of stations or are transported to a lesser extent by long-range atmospheric transport (LRAT) from South America. The values of the ΣLMW/ΣHMW ratio in sediments indicate that petrogenic sources contribute to PAH contamination, but among the six PAH ratios tested, petrogenic sources were identified as dominant in approximately 17-19% of cases. Lack of coherence in the obtained results confirms the mixed origin of PAHs in the studied samples. Although the differentiation of PAHs sources is still ambiguous, caution is recommended in light of the Antarctic system's evident and rapid response to global and local PAH emissions, and the dependency of accumulation and release cycle processes on weather conditions. A reduction in petrol usage in favour of renewable energy sources, and restriction of tourism are strongly recommended for better preservation of the pristine Antarctic environment.

First evaluation of wastewater discharge influence on marine water contamination in the vicinity of Arctowski Station (Maritime Antarctica).

In Antarctica, waste is generated mainly during scientific research programmes and related logistics. In this study, the impact of wastewater on the western shore of Admiralty Bay was investigated during austral summer in 2017 and 2019. A range of physicochemical parameters and the presence of selected trace metals, formaldehyde and different groups of surfactants were determined in wastewater coming from Arctowski Station and in nearby coastal waters. The presence of selected trace metals (e.g., Cr: 2.7-4.4 µg/L; Zn: 15.2-37.3 µg/L; and Ni: 0.9-23.3 µg/L) and the sums of cationic (0.3-1.5 mg/L), anionic (3.1-1.7 mg/L), and non-ionic (0.6-2.4 mg/L) surfactants in wastewater indicated the potential influence of anthropogenic factors on sea water. The determined surfactants are found in many hygiene products that end up in the waste water tank after human use and, if untreated, can be released into surface waters with discharge. In addition, the levels of some trace metals indicate that they cannot come only from natural sources, but are the result of human activity. The reported data show disturbances in the marine environment caused by non-treated wastewater discharge, e.g. by comparing the obtained results from the values of the no observed effect concentrations (NOECs) on selected Antarctic bioindicators, and provide information for the implementation of proper wastewater treatment at any Antarctic station in the future.

Interrelation of quality parameters of surface waters in five tidewater glacier coves of King George Island, Antarctica.

For further understanding of glacial meltwater's (GMW) impacts on marine environments, five coves adjacent to diverse glaciers of King George Island, Antarctica were investigated through surface measurements of water quality parameters. Measurements were conducted 49 times during January, February and March of 2019, with sampling performed in unprecedently close proximity to glacial fronts (<50 m distance from glacier termini in each cove) to create a unique dataset. Four out of five of the coves were inspected through vertical profiling to show water-column stratification. The findings showed synchronized GMW influence causing decreases of salinity, temperature, and dissolved organic matter contents, combined with increased pH, turbidity, and dissolved oxygen values. GMW presence was most correlated with dissolved organic matter content (93% of the cases >0.5 correlation noted with either turbidity or salinity) and least correlated with water temperature (from 22% to 77% of the cases with >0.5 correlation, dependent on the cove). In contrast to previous studies, the pH values of seawater infused with GMW were higher than those of the surrounding water. GMW was shown to stay in the boundary surface layer of the water column. Phytoplankton pigment quantities depending on the localization, time and distance from the glacial termini presented varied response to GMW (positive, negative or ambivalent with hotspots of simultaneous high GMW and phytoplankton quantities). The positive response to glacial water input was more often noted in measurements of phycoerythrin (from 0 to 80% of the cases depending on the cove) rather than chlorophyll A (from 0 to 25%) and maximum quantities of both biological pigments were found at a depth of approximately 5-10 m.

Seashore sediment and water chemistry at the Admiralty Bay (King George Island, Maritime Antarctica) - Geochemical analysis and correlations between the concentrations of chemical species.

This study covers water and sediment chemical characteristics by the western shore of Admiralty Bay (King George Island, Antarctica) in 2016. Chemical processes between sediment and water have been described based on the determination of ions, metals, non-metals, and TOC concentrations. Rock weathering is an important source of Fe, Ni, Co, Al in the seashore area. The PCA shows the impact of acidification in the release metals from sediment. Our results indicate that riverine mineral fluxes need to be accounted for as the volume of melt increases in response to climate change. Based on geoaccumulation indexes (anthropogenic fingerprint), we observed an increased concentration of Pb (Igeo = 1.643), in the lake near station facilities and Cd in the area of Ecology Glacier (Igeo > 1.389). Taking into account climate change and the intensification of anthropopressure, our study indicates that Antarctica requires a special focus on the seasonal dynamics of mineral content and pollution assessment.

Determination of polycyclic aromatic hydrocarbons (PAHs) and other organic pollutants in freshwaters on the western shore of Admiralty Bay (King George Island, Maritime Antarctica).

Organic contamination in freshwater samples has never been investigated at the western shore of Admiralty Bay. Therefore, the presence of polycyclic aromatic hydrocarbons (PAHs) in five different sites distributed along a shore running from the Arctowski Station to the Baranowski Glacier was studied. Moreover, organic compounds such as n-alkanes, toluene and ethylbenzene were also noted. Increased ΣPAHs in late Austral summer 2016 are the result of long-range atmospheric transport of air masses from South America, confirmed by 10-day backward air mass trajectories analysis. The presence of n-alkanes and other hydrocarbons, as well as the evaluation of PAH indices (e.g. ΣLMW/ΣHMW* > 1), shows the use of fuel and indicate local human activity. As a final conclusion, our analysis indicates a mixed origin of PAHs (global and local). The presence of PAHs and other hydrocarbons in the water environment may constitute a potentially negative effect on the Antarctic ecosystem and it should be investigated in detail during further research (//*ΣLMW-sum of low molecular weight PAHs (two- and three-ring PAHs); ΣHMW-sum of high molecular weight PAHs (four- and five-ring PAHs)//). Graphical abstract.

Impact of a newly-formed periglacial environment and other factors on fresh water chemistry at the western shore of Admiralty Bay in the summer of 2016 (King George Island, Maritime Antarctica).

This study provides a comprehensive analysis of the inorganic chemistry of flowing water at the western shore of Admiralty Bay. In the water samples, ions, and major and trace metals (and B) were detected and quantified. Additionally, the parameters of pH, specific electrolytic conductivity (SEC25) and total organic carbon (TOC) were determined. Moreover, multivariate data set was created and Principal Component Analysis (PCA) was performed. Generally, the water has low total content of the measured mineral constituents <100mgL-1. PCA analysis we distinguished two groups of chemical variables shaping water chemistry in the investigated creeks: I - components of marine aerosol origin (presence of Na+, Cl- and B) and II - those associated with chemical weathering processes (presence of Al and Fe). Furthermore, the results showed that the flowing water in the newly-formed periglacial areas (formed over the last 30years) are rich in easily soluble Al and Fe and have lower total measured contents of mineral constituents during the summer period than creeks in non-glacial catchments. Permafrost influence on water chemistry is difficult to identify. The rather insignificant difference between TOC concentrations in waters during summer indicates that permafrost is not a store of organic matter in the studied area. Moreover, local biological factors (lichens and mosses) and those limited to the sea-shore vicinity (seabirds and mammals activity) are significant sources of PO43-, NO3-, and NH4+. Despite the described geological and biological features influencing water chemistry, the impact of anthropogenic activity still needs to be verified, especially in terms of heavy metal concentrations.