The effects of the IM1-12Br ionic liquid and the oxytetracycline mixture on selected marine and brackish microorganisms.

The number of applications and commercialized processes utilizing ionic liquids has been increasing, and it is anticipated that this trend will persist and even intensify in the future. Ionic liquids possess desirable characteristics, such as low vapor pressure, good water solubility, amphiphilicity, and stability. Nevertheless, these properties can influence their environmental behavior, resulting in resistance to biotic and abiotic degradation and subsequent water contamination with more harmful derivatives. However, there is a notable scarcity of data regarding the impact of mixtures comprising ionic liquids and other micropollutants. Identifying potential potentiation of ionic liquids (Ils) toxicity in the presence of other xenobiotics is a proactive risk assessment measure. Therefore, the study aims to fill an important knowledge gap and identify possible interactions between imidazolium-based ionic liquid (IM1-12Br) and the common antibiotic oxytetracycline (OXTC). During 11-day experiments, selected marine, brackish and freshwater microorganisms (diatom Phaeodactylum tricornutum, cyanobacterium Microcystis aeruginosa and green algae Chlorella vulgaris) were exposed to binary mixtures of target substances. The assessed responses encompassed chlorophyll a kinetic parameters related to photosynthesis efficiency, as well as pigment concentrations, specifically phycobilin content. Additionally, the impact on the luminescent marine bacterium Aliivibrio fischeri has been evaluated. Significant effects on the growth, photosynthetic processes, and pigment content were observed in all the targeted microorganisms. The concentration addition (CA) and independent action (IA) mathematical models followed by the Model Deviation Ratio (MDR) evaluation enabled the identification of mainly synergistic interactions in the studied mixtures. The findings of present study offer valuable insights into the impacts of ionic liquids and other organic micropollutants.

Effects of beach wrack on the fate of mercury at the land-sea interface - A preliminary study.

Since the 1970s, the amount of aquatic plants and algae debris, called beach wrack (BW), has increased along the shores of industrialised regions. The strong ability of primary producers to accumulate pollutants can potentially result in their deposition on the beach along with the BW. Despite that, the fate and impact of such pollutants on sandy beach ecosystems have not been investigated so far. This study examines the fate of neurotoxic mercury and its labile and stable fractions in BW on sandy beaches of the Puck Bay (Baltic Sea). In addition to BW, beach sediments and wrack-associated macrofauna were also analysed. Rough estimations showed that Puck Bay beaches (58.8 km) may be a temporary storage of 0.2-0.5 kg of mercury, deposited on them along with the BW annually. A large proportion of Hg (89 ± 16%) in a BW was labile and potentially bioavailable. The contribution of Hg fractions in the BW was conditioned by the degree of its decomposition (molar C:N:P ratio). With the progressive degradation of BW, a decrease in the contribution of Hg adsorbed on its surface with a simultaneous increase in the proportion of adsorbed (intracellular), mercury was observed. BW accumulation decreased oxygen content and redox potential and increased methylmercury content in underlying sediments, indicating methylation. Hg concentrations in the studied fauna were up to 4 times higher than in the BW. The highest values occurred in a predatory sand bear spider and the lowest in a herbivorous sand hopper. Regardless of trophic position, most of Hg (92-95%) occurred as an absorbed fraction, which indicates about a 30% increase in relation to its share of BW. These findings suggest the significant role of BW as a mercury carrier in a land-sea interface and increased exposure of beach communities to the adverse effects of mercury in coastal ecosystems.

Micropollutants in urban wastewater: large-scale emission estimates and analysis of measured concentrations in the Baltic Sea catchment.

Wastewater treatment plants (WWTPs) transmit many chemical contaminants to aquatic environments. Quantitative data on micropollutant emissions via WWTPs are needed for environmental risk assessments and evaluation of mitigation measures. This study compiled published data on substances analysed in effluents from WWTPs in the Baltic Sea region, assessed country related differences in the data sets and estimated micropollutant inputs to the Baltic Sea catchment. Concentration data were found for 1090 substances analysed at 650 WWTPs. Heterogeneity and low number of data points for most substances hindered adequate comparisons of country specific concentrations. Emission estimates were made for the 280 substances analysed in at least five WWTPs in years 2010 to 2019. For selected substances, mass loads were compared to previously published estimations. The study provides data useful for national and Baltic Sea-scale pressure analysis and risk assessments. However, it also highlights the need for broad scope monitoring of micropollutants in wastewater.

The Toxic Effects of Antibiotics on Freshwater and Marine Photosynthetic Microorganisms: State of the Art.

Antibiotic residues have been commonly detected worldwide in freshwater, estuarine, and marine ecosystems. The review summarizes the up-to-date information about the toxic effects of over 60 antibiotics on nontarget autotrophic microorganisms with a particular focus on marine microalgae. A comprehensive overview of the available reports led to the identification of significant knowledge gaps. The data on just one species of freshwater green algae (Raphidocelis subcapitata) constitute 60% of the total information on the toxicity of antibiotics, while data on marine species account for less than 14% of the reports. Moreover, there is a clear knowledge gap regarding the chronic effects of antibiotic exposure (only 9% of studies represent exposition time values longer than 7 days). The review summarizes the information on different physiological endpoints, including processes involved in photosynthesis, photoprotective and antioxidant mechanisms. Currently, the hazard assessment is mostly based on the results of the evaluation of individual chemicals and acute toxicity tests of freshwater organisms. Future research trends should involve chronic effect studies incorporating sensitive endpoints with the application of environmentally relevant concentrations, as well as studies on the mixture effects and combined environmental factors influencing toxicity.

Presence of mercury and methylmercury in Baltic Sea sediments, collected in ammunition dumpsites.

Methylmercury (MeHg) is the most toxic and dangerous form of mercury occurring in the environment. MeHg is highly bioaccumulative in organisms and undergoes biomagnification via the food chain. In the Baltic Sea munition dumpsites, methylmercury can be formed from mercury fulminate contained in primary explosives, as environmental conditions there favour methylation. MeHg in analysed sediments ranged from 19 to 2362 pg g-1d.w., the concentration of mercury (HgTOT) ranged from 4 to 294 ng g-1 d.w., and the values of MeHg/Hg ratio ranged from 0.1 to 2.0%. The obtained results confirmed that munition dumpsites are a source of mercury. The concentration of MeHg is elevated in a wider area than immediately next to dumped munitions. Presented results suggest that physical processes responsible for sediment and near-bottom water movement are diffusing MeHg signal, making munition dumpsites rather a diffuse source of MeHg than a number of point sources associated with particular munitions.

Exposure status of sea-dumped chemical warfare agents in the Baltic Sea.

About 50 000 tons of chemical weapons (CW) were dumped to the Baltic Sea after the Second World War. Munitions are located in the deep areas of the Baltic Sea, and there they act as a point source of contamination to the ecosystem. Corroded munitions release chemical warfare agents (CWAs) to nearby water and sediments. In this study we investigated known dumpsites (Bornholm, Gotland and Gdansk Deep) and dispersed chemical munitions, to evaluate the extent of contamination of nearby sediments, as well as to assess the degradation process of released CWA. It was found that CWA-related phenylarsenic chemicals (Clark I, Clark II and Adamsite) and sulfur mustard are released to the sediments and undergo environmental degradation to chemicals, of which some remain toxic. The extent of pollution of released CWAs and their corresponding degradation products reaches more than 250 m from the CW objects, and seem to follow a power curve decrease of concentration from the source. Bornholm Deep is characterised with the highest concentration of CWAs in sediments, but occasional concentration peaks are also observed in the Gdansk Deep and close to dispersed munitions. Detailed investigation of spreading pattern show that the range of pollution depends on bottom currents and topography.

Volcanic related methylmercury poisoning as the possible driver of the end-Devonian Mass Extinction.

The end-Devonian global Hangenberg event (359 Ma) is among the most devastating mass extinction events in Earth's history, albeit not one of the "Big Five". This extinction is linked to worldwide anoxia caused by global climatic changes. These changes could have been driven by astronomical forcing and volcanic cataclysm, but ultimate causes of the extinction still remain unclear. Here we report anomalously high mercury (Hg) concentration in marine deposits encompassing the Hangenberg event from Italy and Austria (Carnic Alps). The Hangenberg event recorded in the sections investigated can be here interpreted as caused by extensive volcanic activity of large igneous provinces (LIPs), arc volcanism and/or hydrothermal activity. Our results (very large Hg anomalies) imply volcanism as a most possible cause of the Hangenberg event, similar to other first order mass extinctions during the Phanerozoic. For the first time we show that apart from anoxia, proximate kill mechanism of aquatic life during the event could have been methylmercury formed by biomethylation of a volcanically derived, huge concentration of inorganic Hg supplied to the ocean. Methylmercury as a much more toxic Hg form, potentially could have had a devastating impact on end-Devonian biodiversity, causing the extinction of many pelagic species.

Submarine groundwater discharge as a source of pharmaceutical and caffeine residues in coastal ecosystem: Bay of Puck, southern Baltic Sea case study.

Even though the occurrence of pharmaceuticals in the water environment is thought to be a potential problem for human health and aquatic organisms, the level of knowledge of their sources and presence in the marine ecosystem is still insufficient. Therefore, this study was designed to determine the emergence of sixteen pharmaceuticals and caffeine in groundwater, submarine groundwater discharge (SGD), rivers and coastal seawater in the southern Baltic Sea. It has been recognized that chemical substances load associated with SGD can affect coastal ecosystems equally or even greater than surface runoff. Hence, the Bay of Puck, which is an active groundwater discharge area, has been chosen as a model study site to assess the preliminary risk of pharmaceutical and caffeine residues supply in coastal ecosystem. A special focus was placed on tracing the possible sources of pollution for groundwater and SGD based on the composition of collected samples. Five pharmaceuticals (carbamazepine, sulfapyridine, sulfamethoxazole, ketoprofen and diclofenac) and caffeine were detected in varying concentrations from below the detection limit to 1528.2 ng L-1. Caffeine and diclofenac were the most widespread compounds. Groundwater was mostly enriched in the analysed compounds and consequently SGD has been recognized as an important source of identified pharmaceutical and caffeine residues to the Bay of Puck. A predicted no-effect concentration (PNEC) was determined in order to perform an environmental risk assessment of five pharmaceuticals and caffeine detected in water samples. Finally, future challenges and potential amendments in monitoring strategies are discussed.

Impact of hydrotechnical works on outflow of mercury from the riparian zone to a river and input to the sea.

The aim of this research was to assess the impact of hydrotechnical works within the riverbed and riparian zone on the mobility of mercury in soil and its outflow to the river and the sea. Deepening and reconstruction of the riverbed or the cutting of reeds, influenced the fate of mercury in the river system. However, only activitis that disturbed the riperian zone increased mobilization of Hg in soils. Hg transformations in these places were controled by inflow of fresh organic matter in soil and sediments as well as by oxidation-reduction potential. In areas where reducing conditions occurred, mercury released from the soil was incorporated into the sediment. However, in areas where oxidizing conditions prevailed in the sediment, mercury flowing out of the soil occurred mainly in dissolved form and most of it was transported downstream from where it could reach the sea.

Sea-dumped ammunition as a possible source of mercury to the Baltic Sea sediments.

After World War II, as a move toward Germany demilitarization, up to 385,000 t of munitions were sunk in the Baltic Sea. Munition containing various harmful substances, including chemical warfare agents (CWA) and explosives, that can affect marine biota were dumped on the seafloor. Some of those objects contained mercury, either as elemental mercury or mercury compounds (e.g., mercury fulminate, a common explosive primer), and thus could act as a specific local source of mercury in the dumping areas. Unfortunately, there is a lack of information on how dumped munitions impact the mercury concentrations in the Baltic Sea sediments. This report aims to answer the question how much sedimentary mercury in the dumping areas originates from munitions and to determine to what extent the mercury present in those areas originates from mercury fulminate. Concentrations of total sedimentary mercury- HgTOT in samples collected from conventional (Kolberger Heide) and chemical (Bornholm Deep) munitions dumping sites are characterized by high variability. However, an increase in HgTOT concentrations was observed with a decreasing distance to particular munition objects at both study sites. Moreover, mercury speciation in sediments from Kolberger Heide proves that the mercury there can be traced back directly to mercury fulminate. Results of our study confirm that munitions dumpsites are a local point sources of mercury. Due to the ecosystem constrains, varying transport modes and pathways, and both unknown and varying decomposition rates, these sea-bed mercury concentrations are hard to evaluate quantitatively. Therefore we recommend that further detailed studies should be conducted to assess sedimentary mercury provenience in munitions dumpsites more accurately.

Legacy and emerging pollutants in the Gulf of Gdansk (southern Baltic Sea) - loads and distribution revisited.

Coastal marine areas of densely populated countries are exposed to a wide array of human activities having an impact on their ecological status. The Baltic Sea is particularly susceptible to pollution by hazardous substances (limited water exchange, shallowness, and large catchment area). Polish media regularly reports ecological catastrophes in the Gulf of Gdansk area caused by eg. shipwrecks leaking. Thus, there is a need of a broad scientific based report on recent contaminant loads and distribution. In this review paper, we report loads of contaminants from different obvious and non-obvious sources. We also gather data on legacy and new emerging contaminant concentrations measured in the Gulf of Gdansk within the last decade (2008-2018). The paper also includes available biological effect measurements performed recently as well as a summary of needs and gaps to be filled for the development of reliable risk assessment.

Presence, concentrations and risk assessment of selected antibiotic residues in sediments and near-bottom waters collected from the Polish coastal zone in the southern Baltic Sea - Summary of 3years of studies.

Concentrations of selected antibiotic compounds from different groups were measured in sediment samples (14 analytes) and in near-bottom water samples (12 analytes) collected in 2011-2013 from the southern Baltic Sea (Polish coastal zone). Antibiotics were determined at concentration levels of a few to hundreds of ng g-1 d.w. in sediments and ng L-1 in near-bottom waters. The most frequently detected compounds were sulfamethoxazole, trimethoprim, oxytetracycline in sediments and sulfamethoxazole and trimethoprim in near-bottom waters. The occurrence of the identified antibiotics was characterized by spatial and temporal variability. A statistically important correlation was observed between sediment organic matter content and the concentrations of sulfachloropyridazine and oxytetracycline. Risk assessment analyses revealed a potential high risk of sulfamethoxazole contamination in near-bottom waters and of contamination by sulfamethoxazole, trimethoprim and tetracyclines in sediments. Both chemical and risk assessment analyses show that the coastal area of the southern Baltic Sea is highly exposed to antibiotic residues.

Contamination of the southern Baltic Sea waters by the residues of selected pharmaceuticals: Method development and field studies.

In this study the occurrence of thirteen pharmaceuticals in seawaters collected from southern Baltic Sea was evaluated for the first time. It was performed by applying newly developed analytical procedure. The method was characterized in terms of its basic validation parameters as well as matrix effects, extraction efficiency and absolute recovery. The results were expressed as result ± expanded uncertainty, which was estimated according to the Guide to the Expression of Uncertainty in Measurement. Additionally, in order to verify the influence of variable parameters of the analyzed samples on method performance parameters, chemometric analysis was carried out. The obtained results revealed that residues of pharmaceuticals were present in seawaters at a concentration level of ng L(-1). Trimethoprim, sulfamethoxazole and enrofloxacin were most frequently detected compounds. The highest concentration was determined for ketoprofen (135.0 ± 10.9 ng L(-1)). Marine pollution potential hotspots were found in enclosed or semi-enclosed bodies of water.

A new approach for the estimation of expanded uncertainty of results of an analytical method developed for determining antibiotics in seawater using solid-phase extraction disks and liquid chromatography coupled with tandem mass spectrometry technique.

Although the uncertainty estimate should be a necessary component of an analytical result, the presentation of measurements together with their uncertainties is still a serious problem, especially in the monitoring of the presence of pharmaceuticals in the environment. Here we discuss the estimation of expanded uncertainty in analytical procedures for determining residues of twelve pharmaceuticals in seawaters using solid-phase extraction (SPE) with H2O-Philic BAKERBOND speed disks and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Matrix effects, extraction efficiency and absolute recovery of the developed analytical method were determined. A validation was performed to obtain the method's linearity, precision, accuracy, limits of detection (LODs) and quantification (LOQs). The expanded uncertainty of the data obtained was estimated according to the Guide to the Expression of Uncertainty in Measurement and ISO 17025:2005 standard. We applied our method to the analysis of drugs in seawaters samples from the coastal area of the southern Baltic Sea. As a result, a new approach (concerning the uncertainty estimation as well as the development of analytical method) to the analysis of pharmaceutical residues in environmental samples is presented. The information given here should facilitate the introduction of uncertainty estimation in chromatographic measurements on a much greater scale than is currently the case.