Bioaccumulation of organotin compounds in the marbled electric ray (Torpedo marmorata) in the northern Adriatic Sea.

Organotin compounds (OTC), tri-, di- and monobutyl tin, were determined in the tissues of marbled electric ray (Torpedo marmorata) in the Adriatic Sea. Marbled electric ray specimens were provided by local fishermen from three localities in the northern Adriatic: area close to the shipyard in Seca, the natural protected area Strunjan Nature Reserve and along the west Istrian coast. To assess the concentration of OTC in the environment, sediment samples were also analysed. After an adequate extraction of OTC from both matrices, their concentrations were determined by GC-ICP-MS. The results indicate that the accumulation of TBT (tributyltin) and DBT (dibutyltin) in the marbled electric ray is related to the possible pollution sources, since their total concentrations were significantly higher (p < 0.001) in the area close to the shipyard (up to 69 µg Sn kg-1, w.w.) in comparison to the other two areas less affected by direct pollution (up to 7 µg Sn kg-1, w.w.). TBT concentrations ranged from 2 to 42 µg Sn kg-1, w.w., DBT concentrations were in the range from 2 to 22 µg Sn kg-1, w.w., and MBT concentrations were mostly below the detection limit with the highest up to 4 µg Sn kg-1, w.w. The proportion of the three determined congener concentrations in sediment samples indicate a temporally older pollution with these compounds, with prevailing DBT and MBT concentrations up to 30 µg Sn kg-1, w.w., and much lower TBT concentrations up to 7 µg Sn kg-1, w.w. According to our results, marbled electric ray could be considered as an ideal bioindicator of environmental pollution due to its ecological characteristics.

Composting of recovered rock wool from hydroponics for the production of soil amendment.

Due to its fibrous structure and high water holding capacity, rock mineral wool (RMW) has boosted the development of hydroponics. Consequently, the amount of waste RMW has also increased tremendously, which has stimulated the research and development of RMW reuse options. In this study, composting and degradability of RMW from hydroponics (gRMW) were tested in combination with different ratios of biowaste compost, including physical and chemical properties of the starting and final materials, and potential ecological hazards of the final product. gRMW had high water holding capacity and low organic matter content, which was easily degradable. Limits of toxic elements according to EU regulation were not exceeded. Degraded gRMW mixtures with compost did not exhibit toxicity to plants or aquatic bacteria and showed intermediate or limited habitat function for earthworms, which preferred the sole gRMW not mixed with compost. Overall, degraded gRMW exhibited parameters of safe soil amendment.

Determination of copper and other trace elements in serum samples from patients with biliary tract cancers: prospective noninterventional nonrandomized clinical study protocol.

BACKGROUND: Biliary tract cancers (BTCs) are usually diagnosed at an advanced stage, when the disease is incurable. Currently used tumor biomarkers have limited diagnostic value for BTCs, so there is an urgent need for sensitive and specific biomarkers for their earlier diagnosis. Deregulation of the homeostasis of trace elements is involved in the carcinogenesis of different cancers, including BTCs. The objective of the study is to determine/compare the total concentrations of copper (Cu), zinc (Zn) and iron (Fe) and the proportions of free Cu and Cu bound to ceruloplasmin (Cp) and the isotopic ratio of 65Cu/63Cu in serum samples from healthy volunteers and cancer patients using inductively coupled plasma-mass spectrometry-based methods (ICP-MS). PATIENTS AND METHODS: In this prospective, noninterventional, nonrandomized study 20 patients and 20 healthy volunteers will be enrolled to identify serum Cu, Zn and Fe levels, Cu isotopic fractionation as a predictive biomarker of response to systemic therapy of BTCs, which will be evaluated by computed tomography. Newly developed analytical methods based on ICP-MS will be applied to metal-based biomarker research in oncology. CONCLUSIONS: In the study the comparison of the total concentration of selected trace elements, the proportion of free Cu and Cu bound to Cp and the isotopic ratio of 65Cu/63Cu in serum samples from healthy volunteers and cancer patients will be conducted to provide the foundation for the development of a BTC cancer screening methodology and the data on their usability as a potential predictive biomarker for BTCs of response to systemic therapy.

Fine particulate matter (PM2.5) exposure assessment among active daily commuters to induce behaviour change to reduce air pollution.

Fine particulate matter (PM2.5), a detrimental urban air pollutant primarily emitted by traffic and biomass burning, poses disproportionately significant health risks at relatively limited exposure during commuting. Previous studies have mainly focused on fixed locations when assessing PM2.5 exposure, while neglecting pedestrians and cyclists, who often experience higher pollution levels. In response, this research aimed to independently validate the effectiveness of bicycle-mounted low-cost sensors (LCS) adopted by citizens, evaluate temporal and spatial PM2.5 exposure, and assess associated health risks in Ljubljana, Slovenia. The LCS quality assurance results, verified by co-location field tests by air quality monitoring stations (AQMS), showed comparable outcomes with an average percentage difference of 21.29 %, attributed to humidity-induced nucleation effects. The colder months exhibited the highest air pollution levels (µ = 32.31 µg/m3) due to frequent thermal inversions and weak wind circulation, hindering vertical air mixing and the adequate dispersion of pollutants. Additionally, PM2.5 levels in all sampling periods were lowest in the afternoon (µ = 12.09 µg/m3) and highest during the night (µ = 61.00 µg/m3) when the planetary boundary layer thins, leading to the trapping of pollutants near the surface, thus significantly affecting diurnal and seasonal patterns. Analysis of exposure factors revealed that cyclists were approximately three times more exposed than pedestrians. However, the toxicological risk assessment indicated a minimal potential risk of PM2.5 exposure. The collaborative integration of data from official AQMS and LCS can enhance evidence-based policy-making processes and facilitates the realignment of effective regulatory frameworks to reduce urban air pollution.

Assessment of dimethyl sulphide odorous emissions during coal extraction process in Coal Mine Velenje.

Underground coal extraction at Coal Mine Velenje occasionally gives rise to odour complaints from local residents. This manuscript describes a robust quantification of odorous emissions of mine sources and a model-based analysis aimed to establish a better understanding of the sources, concentrations, dispersion, and possible control of odorous compounds during coal extraction process. Major odour sources during underground mining are released volatile sulphur compounds from coal seam that have characteristic malodours at extremely low concentrations at micrograms per cubic metre (µg/m3) levels. Analysis of 1028 gas samples taken over a 6-year period (2008-2013) reveals that dimethyl sulphide ((CH3)2S) is the major odour active compound present in the mine, being detected on 679 occasions throughout the mine, while hydrogen sulphide (H2S) and sulphur dioxide (SO2) were detected 5 and 26 times. Analysis of gas samples has shown that main DMS sources in the mine are coal extraction locations at longwall faces and development headings and that DMS is releasing during transport from main coal transport system. The dispersion simulations of odour sources in the mine have shown that the concentrations of DMS at median levels can represent relatively modest odour nuisance. While at peak levels, the concentration of DMS remained sufficiently high to create an odour problem both in the mine and on the surface. Overall, dispersion simulations have shown that ventilation regulation on its own is not sufficient as an odour abatement measure.

Environmental Acceptability of Geotechnical Composites from Recycled Materials: Comparative Study of Laboratory and Field Investigations.

The environmental properties of three geotechnical composites made by recycling wastes were investigated on a laboratory scale and in the field with the use of lysimeters designated for the revitalization of degraded mining sites. Composites were prepared by combining the mine waste with paper-mill sludge and foundry sand (Composite 1), with digestate from municipal waste and paper ash (Composite 2), and with coal ash, foundry slag and waste incineration bottom ash (Composite 3). The results of laboratory leaching tests proved that Composites 1 and 3 are environmentally acceptable, according to the legislative limits, as the potentially hazardous substances were immobilized, while in Composite 2, the legislative limits were exceeded. In the field lysimeters, the lowest rate of leaching was determined for optimally compacted Composites 1 and 3, while for Composite 2 the leaching of Cu was high. This study proved that optimally installed Composites 1 and 3 are environmentally acceptable for use in construction as an alternative to virgin materials, for the revitalization of degraded mining sites or, along with Composite 2, for closure operations with landfills. In this way, locally available waste streams are valorised and channelized into a beneficial and sustainable recycling practice.

Reduction of hexavalent chromium using bacterial isolates and a microbial community enriched from tannery effluent.

We investigated microbial growth in increasing concentrations of hexavalent chromium (Cr(VI)) and its reduction by a microbial community enriched from tannery effluent and by the bacterial strains isolated from the enriched community. The bacterial growth was monitored by measuring the optical cell density (OD650), while the Cr(VI) concentration in the samples was determined using spectrophotometry and liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC-ICP-MS). At a Cr(VI) concentration of 100 mg/L, the isolates affiliated with Pseudomonas aeruginosa (P. aeruginosa) reached higher optical cell densities, but were in general less effective for Cr(VI) reduction than the isolates affiliated with Mammaliicoccus sciuri (M. sciuri). All three M. sciuri isolates and only one of the seven P. aeruginosa isolates were able to reduce 50% of the Cr(VI) with an initial concentration of 100 mg/L within 24 h (pH 7.1), while the six isolates affiliated with P. aeruginosa were less effective. Compared to the isolated, individual bacterial strains, the enriched microbial community was better adapted to the elevated Cr(VI) concentrations, but needed a longer time (48 h) to reduce the Cr(VI) with the same efficacy as the most efficient individual isolates. The ability of the enriched microbial community and the isolated bacterial strains to reduce the Cr(VI) highlights their potential for use in the rapid bioremediation of wastewaters contaminated with Cr(VI).

Simultaneous speciation of chromate, molybdate and arsenate in lysimetric water from geotechnical composites installed in field lysimeters.

Anion-exchange high performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC-ICP-MS) was used for simultaneous speciation of chromate, molybdate and arsenate. The repeatability of measurement tested for multielemental standard solution of chromate, molybdate and arsenate (50 ng mL-1 of Cr, Mo and As, pH 12) was ± 0.9%, ± 4.9% and ± 4.1%, respectively. Limits of quantification (LOQs) were low (0.53 ng mL-1 for chromate and arsenate and 1.03 ng mL-1 for molybdate, expressed as elemental concentrations). A wide linear concentration range (from LOQs to 500 ng mL-1) was obtained. The performances of this method enabled simultaneous speciation analysis in samples of water from lysimeters, in which three geotechnical composites, made of recycled waste, were installed in parallel in compacted and uncompacted, 20 times less dense form. The release of toxic chemical species of elements into lysimetric waters from each composite was studied. The results revealed that the degree of compaction and the composition of composites both have a significant influence on leaching of chromate, molybdate and arsenate. The study proved that multielemental speciation analysis is fast and cost-effective method for investigations of environmental impacts of materials, made from recycled waste, and can be used in other similar applications.

Speciation and Bio-Imaging of Chromium in Taraxacum officinale Using HPLC Post-column ID-ICP-MS, High Resolution MS and Laser Ablation ICP-MS Techniques.

A new analytical procedure for the speciation of chromium (Cr) in plants by high performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC-ICP-MS) was developed using a strong anion-exchange Mono Q column for the separation of the Cr species. To optimize the analytical procedure, Cr complexes were first synthesized from Cr-nitrate with the addition of an excess of ligand (90°C). Cr-oxalate, Cr-malate, Cr-citrate, Cr-aconitate and Cr-quinate complexes and Cr-nitrate (pH 6.5) were chromatographically separated from Cr(VI) by applying linear gradient elution from 100% water to 100% NH4Cl at a flow rate of 1.5 ml min-1 in 10 min. The column recoveries ranged from 100 to 104%. The exception was Cr-aconitate (column recovery 33%), where a quantitative synthesis was not possible. Good repeatability of the measurements (relative standard deviations better than ± 3%) and low limits of detection (below 0.37 ng ml-1 Cr) were achieved for the individual Cr species. The developed analytical procedure was applied to Cr speciation for dandelions (Taraxacum officinale) grown in soil with a high Cr content and a study of the uptake and metabolism of Cr species in dandelions grown in soil with a low Cr content treated with solutions of Cr(VI) or Cr-nitrate (5000 ng ml-1 Cr, pH 6.5) for 48 h. The separated Cr species were quantified by post-column isotope dilution ICP-MS, while the identification was based on retention times and was also supported by mass spectra obtained with high resolution mass spectrometry (HR-MS). The data indicate that for dandelions grown in Cr-rich soil and that treated with Cr-nitrate (pH 6.5), the Cr was mainly accumulated in the roots, while in plants treated with Cr(VI) (pH 6.5), the Cr was evenly distributed between the roots and the leaves. The Cr species found in dandelion roots and leaves were Cr-aconitate, Cr-malate, and Cr-quinate. The results revealed that Cr(VI) was completely reduced and metabolized to Cr(III) complexes. LA-ICP-MS data showed that the Cr in a leaf of dandelion grown in Cr-rich soil was localized mainly at the apex of the leaf.

Spatial and temporal variability and sources of dissolved trace elements in the Sava River (Slovenia, Croatia).

The spatial and temporal variability of dissolved trace elements (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sb, Sr, Ti, U, V and Zn) in the upper and middle reaches of the Sava River during two campaigns (2007/2008 and 2017/2018) was examined. The study also included important tributaries and wastewater effluents. No crucial change in metal concentrations in the Sava River water between the two sampling periods was detected. Elements Co, Cr, Cu, Fe, Sb and Zn had higher concentrations at several sites in the first period, whereas Ba, Cd and Pb in the second period. The influence of wastewater discharges proved to be negligible. The highest levels of potentially toxic metals (Cd, Cr, Cu, Sb, V and Zn) were found downstream of the industrial town of Sisak. Concentration-discharge relationship of dissolved elements showed a chemostatic behaviour for As, Cr, Cu, Sr and V and chemodynamic behaviour for all other elements. The UNMIX model, used to identify and quantify metal sources, indicated that soil weathering was the main source of most elements (Al, As, Ba, Co, Cu, Fe, Li, Ni, Sb, Sr and V), with an anthropogenic contribution for Cd, Mo, Pb, Ti and Zn, while Mn and U were associated with colloid formation. The Sava River was defined as moderately polluted regarding metals, whose water quality meets environmental quality standards (EQS). These results may help to better understand the behaviour of dissolved metals in rivers under anthropogenic pressure and to control pollution in the Sava River Basin.

High spatial resolution imaging of cisplatin and Texas Red cisplatin in tumour spheroids using laser ablation isotope dilution inductively coupled plasma mass spectrometry and confocal fluorescence microscopy.

Oncology research uses different imaging techniques to provide information about the spatial distribution of the chemotherapy drugs used for the targeted tissues. Among them, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is increasingly being used to track the spatial distribution of metal-based chemotherapeutics in different tissue samples. In this investigation, instrumental parameters were optimized for the bioimaging of Pt in HT29 tumour spheroids treated with cisplatin (CDDP) or Texas Red cisplatin (TR-CDDP) using LA-ICP-MS. A high spatial resolution, using pixel dimensions of 2.0 µm × 2.5 µm, and a high sensitivity, with the limits of detection (LOD) better than 0.78 mg kg-1 Pt, was achieved. Matrix-matched gelatine standards and/or isotope dilution (ID) analyses were used to quantify the amount of Pt. Differences between the results of the Pt concentrations determined by the two quantification were less than 4%. The results of the LA analysis revealed that the Pt in the CDDP-treated tumour spheroids was localized primarily in the outer rim of the spheroids and to a lesser extent in the intermediary layer and the necrotic core. Due to the steric effects, significantly lower Pt concentrations were accumulated in the spheroids treated with TR-CDDP (2.2 times lower than in CDDP-treated spheroids, normalized to the spheroid volume), while the Pt was mostly distributed in the areas of the outer rim. Finally, imaging with confocal fluorescence microscopy, which is commonly used in oncology research, was compared with that by LA-ICP-MS. The results of the two complementary techniques demonstrated good agreement in terms of the spatial distribution of the TR-CDDP, while the intensity of the fluorescence matched well with the concentrations of Pt determined with LA-ICP-MS.

Priority and emerging organic microcontaminants in three Mediterranean river basins: Occurrence, spatial distribution, and identification of river basin specific pollutants.

There is a worldwide growing use of chemicals by our developed, industrialized, and technological society. More than 100,000 chemical substances are thus commonly used both by industry and households. Depending on the amount produced, physical-chemical properties, and mode of use, many of them may reach the environment and, notably, the aquatic receiving systems. This may result in undesirable and harmful side-effects on both the human and the ecosystem's health. Mediterranean rivers are largely different from Northern and Central European rivers in terms of hydrological regime, climate conditions (e.g. air temperature, solar irradiation, precipitation), and socio-economics (e.g. land use, tourism, crop types, etc.), with all these factors leading to differences in the relative importance of the environmental stressors, in the classes and levels of the pollutants found and their environmental fate. Furthermore, water scarcity might be critical in affecting water pollution because of the lowered dilution capacity of chemicals. This work provides raw chemical data from different families of microcontaminants identified in three selected Mediterranean rivers (the Sava, Evrotas, and Adige) collected during two sampling campaigns conducted in 2014 and 2015 in three different matrices, namely, water, sediments, and biota (fish). More than 200 organic micropollutants were analyzed, including relevant groups like pharmaceuticals, personal care products, perfluorinated compounds, pesticides, pyrethroid insecticides, flame retardants, and persistent organic pollutants. Data obtained were summarized with some basic statistics for all compound families and matrices analyzed. Observed occurrence and spatial patterns were interpreted both in terms of compound physical-chemical properties and local environmental pressures. Finally, their spatial distribution was examined and their ecotoxicological risk in the water phase was assessed. This allowed locating, at each basin, the most polluted sites ("hot spots") and identifying the respective river basin specific pollutants (RBSPs), prioritizing them in terms of the potential ecotoxicological risk posed to the aquatic ecosystems.

Study of interferences and procedures for their removal in the spectrophotometric determination of ammonium and selected anions in coloured wastewater samples.

Ammonium and selected anions were determined in wastewater samples with highly complex matrices by spectrophotometry using the reagent-kit method. For this purpose, the interferents of coloured compounds and S2-, SO32-, CO32- and Cl-, which are often present in wastewater samples, were systematically investigated in the spectrophotometric determination of ammonium, nitrate, chloride, sulphate, fluoride and phosphate. After this, innovative procedures for their removal were proposed. For sample decolourization, a DEAE column was used to determine ammonium, while a Florisil column was used for the colour removal and anions' determination. S2- and CO32- were eliminated from the samples by adding HCl or HNO3, which transformed them into gases H2S and CO2. The stepwise addition of CaCl2 to the sample, adjusted to pH 8, initiated the formation of CaSO3, which was removed by filtration. Cl- was removed by the addition of Ag2O, which formed a AgCl precipitate that was removed from the solution by filtration. The accuracy of the determination was tested with spike-recovery tests, which showed recoveries for the analytes in the spiked samples ranging from 95 to 105%. The repeatability of the measurements of nitrate, chloride, sulphate and phosphate in the wastewater samples was better than ±1%, while that for the ammonium and fluoride samples was ±2 and ±5%, respectively. The data from the present investigation revealed that the developed procedures for the decolourization and stepwise removal of interferents enabled accurate spectrophotometric determination of ammonium, nitrate, chloride, sulphate, fluoride and phosphate by using cuvette tests in complex wastewater and environmental water samples.

Kinetics of interaction of Cr(VI) and Cr(III) with serum constituents and detection of Cr species in human serum at physiological concentration levels.

A novel analytical method, based on monolithic convective interaction media (CIM) chromatography coupled to UV and inductively coupled plasma mass spectrometry (ICP-MS) detectors, was developed to investigate the kinetics of interactions of Cr(VI) and Cr(III) with serum constituents, and perform Cr speciation at physiological concentration levels. Cr(VI) was separated from Cr-transferrin (Cr-Tf) and Cr-albumin (Cr-HSA) on a CIM diethylamino (DEAE) column using linear gradient elution from 100% buffer A (50 mM Tris-HCl + 10 mM NaHCO3, pH 7.4) to 60% buffer B (buffer A + 2 M NH4Cl) in 10 min at a flow rate of 1 mL min-1. Good column recovery of separated Cr species (close to 100%) and satisfactory method repeatability (RSDs below 8%) was obtained. Kinetics of interaction of Cr(VI) and Cr(III) with serum constituents were followed after human serum was doubly spiked with enriched 50Cr(VI) and 53Cr(III) solutions, and speciation analysis applied from 5 min up to 48 h after spiking. The results showed that in serum 53Cr(III) rapidly interacted with Tf, while 50Cr(VI) reduction was slow. 48 h after spiking, more than 90% of added 53Cr(III) was bound to Tf and the remaining 10% associated with HSA. About 20% of spiked 50Cr(VI) was still present in serum, while the resulting 50Cr(III) was bound predominantly to Tf. High sensitivity of the developed speciation procedure enabled detection of Cr-Tf complex as the main Cr species in human serum at physiological concentration levels. To the best of our knowledge, Cr-Tf concentrations in serum of unexposed individuals have not been reported yet.

Binding Kinetics of Ruthenium Pyrithione Chemotherapeutic Candidates to Human Serum Proteins Studied by HPLC-ICP-MS.

The development of ruthenium-based complexes for cancer treatment requires a variety of pharmacological studies, one of them being a drug's binding kinetics to serum proteins. In this work, speciation analysis was used to study kinetics of ruthenium-based drug candidates with human serum proteins. Two ruthenium (Ru) complexes, namely [(η6-p-cymene)Ru(1-hydroxypyridine-2(1H)-thionato)Cl] (1) and [(η6-p-cymene)Ru(1-hydroxypyridine-2(1H)-thionato)pta]PF6 (2) (where pta = 1,3,5-triaza-7-phosphaadamantane), were selected. Before a kinetics study, their stability in relevant media was confirmed by nuclear magnetic resonance (NMR). Conjoint liquid chromatography (CLC) monolithic column, assembling convective interaction media (CIM) protein G and diethylamino (DEAE) disks, was used for separation of unbound Ru species from those bound to human serum transferrin (Tf), albumin (HSA) and immunoglobulins G (IgG). Eluted proteins were monitored by UV spectrometry (278 nm), while Ru species were quantified by post-column isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS). Binding kinetics of chlorido (1) and pta complex (2) to serum proteins was followed from 5 min up to 48 h after incubation with human serum. Both Ru complexes interacted mainly with HSA. Complex (1) exhibited faster and more extensive interaction with HSA than complex (2). The equilibrium concentration for complex (1) was obtained 6 h after incubation, when about 70% of compound was bound to HSA, 5% was associated with IgG, whereas 25% remained unbound. In contrast, the rate of interaction of complex (2) with HSA was much slower and less extensive and the equilibrium concentration was obtained 24 h after incubation, when about 50% of complex (2) was bound to HSA and 50% remained unbound.

Monolithic chromatography on conjoint liquid chromatography columns for speciation of platinum-based chemotherapeutics in serum of cancer patients.

BACKGROUND: Monolithic chromatography using convective interaction media (CIM) disks or columns can be used in the separation step of speciation analysis. When different monolithic disks are placed in one housing, forming conjoint liquid chromatography (CLC) monolithic column, two-dimensional separation is achieved in a single chromatographic run. METHODS: Here, we assembled low-pressure (maximum 50 bar) CLC monolithic column, which consists of two 0.34 mL shallow CIM monolithic disks and high-pressure CLC column (maximum 150 bar) from 0.1 mL analytical high performance short bed CIMac monolithic disks. Both the CLC columns constructed from affinity Protein G and weak anion exchange diethylamine (DEAE) disks, were applied for the speciation of cisplatin, oxaliplatin and carboplatin in spiked standard serum proteins, spiked human serum and serum of cancer patients. The analytical performances of the CLC columns used were evaluated by comparing their robustness, selectivity, repeatability and reproducibility. The separated serum proteins were detected on-line by ultraviolet (UV) and eluted Pt species by inductively coupled plasma mass spectrometry (ICP-MS). For accurate quantification of the separated Pt species (unbound Pt-based chemotherapeutic from species associated to transferrin (Tf), human serum albumin (HSA) and Immunoglobulin G (IgG)), post column isotope dilution (ID)-ICP-MS was used. RESULTS: The data from analyses showed that both tested CLC monolithic columns gave statistically comparable results, with the low-pressure CLC column exhibiting better resolving power and robustness. It also enables more effective cleaning of monolithic disks and to analyse larger series of serum samples than the high-pressure CLC column. Analyses of serum samples of cancer patients treated with cisplatin or carboplatin showed that Pt-chemotherapeutics were bound preferentially to HSA (around 80%). The portion of unbound Pt in general did not exceed 2%, up to 5% of Pt was associated with Tf and approximately 20% with IgG. Column recoveries, calculated as a ratio between the sum of concentrations of Pt species eluted and concentration of total Pt in serum samples, were close to 100%. CONCLUSIONS: Low-pressure CLC column exhibited greater potential than high-pressure CLC column, and can be thus recommended for its intended use in speciation analysis of metal-based biomolecules.

The effect of stabilization on the utilization of municipal sewage sludge as a soil amendment.

This study assesses the potential use of different types of stabilized sewage sludge as a soil amendment by considering their physicochemical characteristics, nutritional status, and their trace metal and radionuclide content. The concentrations of trace metals and radionuclides were determined using ICP-OES and gamma-ray spectrometry, respectively. For determining nutritional status and chemical characterization, this study followed standard ISO-recommended procedures. Data analysis revealed that anaerobic sludge contains higher concentrations of Cr, Hg, and Ni compared to aerobic and non-biologically stabilized sludge. A similar observation was observed in the case of 226Ra, 210Pb, 228Ra, and 228Th. Furthermore, the high levels of P and N in aerobic sludge suggest that biologically stabilized sludge has the potential to be a good fertilizer. In addition, the study finds strong evidence that nutrients are involved in the adsorption of metals and radionuclides onto sludge biomass. Overall, eight of the nine studied sludge samples are safe for agricultural use since the concentrations of trace metals fall well below the limits set by Croatian legislation (NN 38/08). In addition, the levels of radionuclides do not pose a radiological risk. This means that soil conditioning with sewage sludge remains a viable strategy for nutrient recovery from municipal waste, although long-term impact assessments of repeated applications are necessary.

Potentially toxic elements in muscle tissue of different fish species from the Sava River and risk assessment for consumers.

Fish from the Sava River are consumed daily by the local people: therefore, concern has been raised about the health implications of eating contaminated fish. In the present study, potentially toxic elements (PTE), such as Zn, Cu, Cr, Ni, Cd, Pb, As, Hg, and methylmercury (MeHg), were determined in ichthyofauna that are commonly consumed. PTE were determined in the fish muscle tissue. Fish were sampled at 12 locations from the source of the Sava River to its confluence with the Danube River during two sampling campaigns, namely; in 2014 under high water conditions and in 2015 under normal water conditions. Due to the different water regimes, different fish species were collected for chemical analysis. We observed that the concentrations of elements analysed in the fish muscle tissue were generally very low, except for those of Hg. Moreover, more than 90% of Hg present in the fish was in its most toxic form, namely MeHg. Especially in fish from the 2015 sampling campaign, Hg and MeHg concentrations increased with fish size, trophic level, and in the downstream direction. In addition, for Pb and As, and to some extent for Cd and Cr, spatial differences were detected in both years. The highest concentrations of PTE were detected in fish from sites with intensive industrial and agricultural activities. The consumption of fish in general does not pose a health risk for the PTE studied, except for Hg/MeHg at selected contaminated sites.

Potentially toxic elements in water, sediments and fish of the Evrotas River under variable water discharges.

Among different stressors like drought, hydro-morphological alterations, and pollution from agricultural activities, nutrients, organic compounds and discharges from wastewater treatment plants (WWTPs), potentially toxic elements (PTE) may also contribute to the overall pollution of the Evrotas River, Greece. Nevertheless, information on pollution of elements in water and sediments in this river is scarcely documented. There is also no information available on the impact of elemental pollution from the aquatic environmental compartments on biota. To fill these gaps, in this study, water, sediment and fish samples were collected from four sampling sites along the Evrotas River under variable flow regimes (July 2015, higher discharge; June 2016, low discharge and September 2016, minimum discharge). Total and dissolved element concentrations in water samples, total and acetic acid extractable contents in sediments, and element concentrations in fish samples were determined by inductively coupled plasma mass spectrometry and significant relationships between samples were established using correlation analysis. The concentrations of PTE (Ni, Cr, Cd, As, Pb, Zn and Cu) in water were generally low, while elevated Ni and Cr contents were found in sediments (up to 150 and 300 mg/kg, respectively), with total Cr concentration in water and sediment being positively correlated. The ecological risk posed by the simultaneous presence of PTE in sediments evaluated by calculating the Probable Effect Concentration Coefficient (PEC-Q), demonstrated that PEC-Qs, which were above the critical value of 0.34, derived mostly from Cr and Ni inputs. Since their mobile sediment fraction was extremely low, Cr and Ni origin is most probably geogenic. The analysis of elements in the target fish species, the Evrotas chub, showed low to moderate PTE concentrations, with Pb being positively correlated with total Pb concentration in water. Moderate Zn concentrations found in fish samples from the Evrotas are possibly derived from pesticides and fertilizers.

Levels of regulated POPs in fish samples from the Sava River Basin. Comparison to legislated quality standard values.

Fish samples of different species (i.e. rainbow trout (Onchorhynchus mykiss), barbel (Barbus barbus) and European chub (Squalius cephalus)) were collected from the Sava River Basin for a preliminary investigation of the levels of PCDD/Fs, PCBs, PBDEs and PFAS as a whole. Concentrations of PCDD/Fs, in terms of pg WHO-TEQ/g ww, were below the maximum limit established at the Commission Regulation (EU) No 1259/2011. On the contrary, when DL-PCBs were also included, levels increase up to 11.7 pg WHO-TEQPCDD/Fs+DL-PCBs/g ww in a particular case, with two samples out of a total of ten exceeding the maximum set at this EU Regulation and the EQS established at the European Directive regarding priority substances in the field of water policy (0.0065 ng WHO-TEQPCDD/Fs+DL-PCBs/g ww). A similar trend was also observed for NDL-PCBs, whit the same two samples, from the lower stretch of the river basin, exceeding the maximum limit allowed at the EU Regulation (125 ng/g ww). For PBDEs, levels found in all the samples exceeded the EQS (0.0085 ng/g ww) up to more than a thousand times and 40% of the samples presented PFOS values above the EQS. Data from this study were compared to values reported at the literature for fish from other geographical areas.