A method for caesium concentration from North Sea and Baltic Sea seawater samples was tested and optimised for offshore concentration of radiocaesium and seawater volumes up to 150 L. The composite ion-exchanger PotassiumNickel Hexacyanoferrate in a Polyacrylnitrile binding matrix (KNiFC-PAN) with 80% of powdered KNiFC per gram of dry residue was used for this study. The optimised method achieved recoveries of around 99% with a bed volume (BV) of 50 mL of KNiFC-PAN and average flow rates of seawater of around 182 BV per hour (e.g. 9.1 L per hour).

• Klíčová slova
• (134)Cs, (137)Cs, Baltic Sea, Composite ion-exchanger, KNiFC-PAN, North Sea, Offshore, Seawater,
• MeSH
• monitorování radiace metody   MeSH
• mořská voda chemie   MeSH
• radioaktivní látky znečišťující vodu analýza   MeSH
• radioizotopy cesia analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• radioaktivní látky znečišťující vodu MeSH
• radioizotopy cesia MeSH

An automatic flow-based system as a front end to liquid chromatography (LC) for on-line dynamic leaching of microplastic materials (polyethylene of medium density and poly(vinyl chloride)) with incurred phthalates and bisphenol A is herein presented. The microplastic particles were packed in a metal column holder, through which seawater was pumped continuously by resorting to advanced flow methodology. Each milliliter of the leachable (bioaccessible) fraction of chemical additives was preconcentrated on-line using a 10 mm-long octadecyl monolithic silica column placed in the sampling loop of the injection valve of a HPLC system that served concomitantly for analyte uptake and removal of the seawater matrix. After loading of the leachate fraction, the LC valve was switched to the inject position and the analytes were eluted and separated by a monolithic column (Onyx C18HD 100 × 4.6 mm) using an optimized acetonitrile/water gradient with UV detection at 240 nm. The automatic flow method including dynamic flow-through extraction, on-line sorptive preconcentration, and matrix clean-up was synchronized with the HPLC separation, which lasted ca. 9 min. The only two currently available multi-component certified reference materials (CRM) of microplastics (CRM-PE002 and CRM-PVC001) were used for method development and validation. Out of the eight regulated phthalates contained in the two CRMs, only the 2 most polar species, namely, dimethyl phthalate and diethyl phthalate as well as bisphenol A, were leached significantly by the seawater in less than 2 h, with bioaccessibility percentages of 51-100%. The leaching profiles were monitored and modeled with a first-order kinetic equation so as to determine the rate constants for desorption in a risk assessment scenario. Intermediate precision values of bioaccessibility data for three batches of CRMs were for the suite of targeted compounds ≤22%. This work for the first time reports a fully automatic flow method with infinite sink capacity (i.e., using a surplus of extracting solution) for the target species able to mimic the leaching of additives from plastic debris across the water body in marine settings under worst-case extraction conditions.

• Klíčová slova
• Automation, Bisphenol A, Dynamic leaching, Microplastics, Phthalates, Seawater,
• MeSH
• automatizace MeSH
• chemické látky znečišťující vodu analýza   MeSH
• chromatografie kapalinová metody   MeSH
• kinetika MeSH
• mořská voda chemie   MeSH
• plastické hmoty analýza   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH
• plastické hmoty MeSH

A surface plasmon resonance (SPR) phenomenon implemented via D-shaped polymer optical fiber (POF) is exploited to realize cortisol biosensors. In this work, two immonosensors are designed and developed for the qualitative as well as quantitative measurement of cortisol in artificial and real samples. The performances of the POF-based biosensors in cortisol recognition are achieved using different functionalization protocols to make the same antibody receptor layer over the SPR surface via cysteamine and lipoic acid, achieving a limit of detection (LOD) of 0.8 pg/mL and 0.2 pg/mL, respectively. More specifically, the use of cysteamine or lipoic acid changes the distance between the receptor layer and the SPR surface, improving the sensitivity at low concentrations of about one order of magnitude in the configuration based on lipoic acid. The LODs of both cortisol biosensors are achieved well competitively with other sensor systems but without the need for amplification or sample treatments. In order to obtain the selectivity tests, cholesterol and testosterone were used as interfering substances. Moreover, tests in simulated seawater were performed for the same cortisol concentration range achieved in buffer solution to assess the immunosensor response to the complex matrix. Finally, the developed cortisol biosensor was used in a real seawater sample to estimate the cortisol concentration value. The gold standard method has confirmed the estimated cortisol concentration value in real seawater samples. Liquid-liquid extraction was implemented to maximize the response of cortisol in liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis.

• MeSH
• biosenzitivní techniky * metody   MeSH
• hydrokortison * analýza   MeSH
• limita detekce MeSH
• mořská voda * analýza   MeSH
• optická vlákna MeSH
• polymery chemie   MeSH
• povrchová plasmonová rezonance * metody   MeSH
• vodní hospodářství * metody   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hydrokortison * MeSH
• polymery MeSH

Some per- and polyfluoroalkyl substances (PFASs) have been detected ubiquitously in the environment. Owing to the polar character conferred by the presence of the carboxylic or sulfonic acid groups and their resistance to degradation, aquatic environments became their major reservoirs, including marine waters. The procedure of PFAS analysis in aqueous matrices consists usually of solid-phase extraction (SPE) followed by high-performance liquid chromatography coupled to tandem mass spectrometry. Moreover, passive sampling approach using various SPE sorbents may be applied. This study deals with the assessment of retention characteristics of a selected group of PFASs in marine water on three sorbent media widely used in SPE or passive sampling techniques. The influence of type of sorbent, matrix pH, salinity and eluent on the PFAS recovery from aquatic samples was investigated. The best overall extraction conditions were found to be at pH 8 and 50%/100% matrix seawater content using Oasis® HLB/Strata™-X as SPE sorbents and methanol as eluent. The matrix properties found to be the most appropriate for extraction of investigated PFASs from aqueous samples (i.e., pH and salinity levels) match well the natural properties of marine and brackish waters. Acid-base behavior was found to be the main driver influencing the recovery of PFASs. These research findings can be used to optimize PFAS extraction conditions from aquatic samples and also to develop efficient extraction procedures for multiresidual analyses.

• Klíčová slova
• Oasis(®) HLB, Oasis(®) WAX, Per- and polyfluoroalkyl substances, Recovery, Seawater, Strata™-X,
• MeSH
• chemické látky znečišťující vodu analýza   izolace a purifikace   MeSH
• extrakce na pevné fázi metody   MeSH
• fluorokarbony izolace a purifikace   MeSH
• kyseliny sulfonové MeSH
• mořská voda chemie   MeSH
• tandemová hmotnostní spektrometrie metody   MeSH
• vysokoúčinná kapalinová chromatografie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH
• fluorokarbony MeSH
• kyseliny sulfonové MeSH

Certification of trace metals in seawater certified reference materials (CRMs) NASS-7 and CASS-6 is described. At the National Research Council Canada (NRC), column separation was performed to remove the seawater matrix prior to the determination of Cd, Cr, Cu, Fe, Pb, Mn, Mo, Ni, U, V, and Zn, whereas As was directly measured in 10-fold diluted seawater samples, and B was directly measured in 200-fold diluted seawater samples. High-resolution inductively coupled plasma mass spectrometry (HR-ICPMS) was used for elemental analyses, with double isotope dilution for the accurate determination of B, Cd, Cr, Cu, Fe, Pb, Mo, Ni, U, and Zn in seawater NASS-7 and CASS-6, and standard addition calibration for As, Co, Mn, and V. In addition, all analytes were measured using standard addition calibration with triple quadrupole (QQQ)-ICPMS to provide a second set of data at NRC. Expert laboratories worldwide were invited to contribute data to the certification of trace metals in NASS-7 and CASS-6. Various analytical methods were employed by participants including column separation, co-precipitation, and simple dilution coupled to ICPMS detection or flow injection analysis coupled to chemiluminescence detection, with use of double isotope dilution calibration, matrix matching external calibration, and standard addition calibration. Results presented in this study show that majority of laboratories have demonstrated their measurement capabilities for the accurate determination of trace metals in seawater. As a result of this comparison, certified/reference values and associated uncertainties were assigned for 14 elements in seawater CRMs NASS-7 and CASS-6, suitable for the validation of methods used for seawater analysis.

• Klíčová slova
• Certified reference material, Dissolved trace metals, Flow injection analysis, HR-ICPMS, Isotope dilution, Seawater, Standard addition calibration,
• Publikační typ
• časopisecké články MeSH

The microbial diversity and functioning around oceanic islands is poorly described, despite its importance for ecosystem homeostasis. Here, we aimed to verify the occurrence of microbe-driven phenanthrene co-oxidation in the seawater surrounding the Trindade Island (Brazil). We also used Next-Generation Sequencing to evaluate the effects of aliphatic and polycyclic aromatic hydrocarbons (PAHs) on these microbial community assemblies. Microcosms containing seawater from the island enriched with either labelled (9-14C) or non-labelled phenanthrene together with hexadecane, weathered oil, fluoranthene or pyrene, and combinations of these compounds were incubated. Biodegradation of phenanthrene-9-14C was negatively affected in the presence of weathered oil and PAHs but increased in the presence of hexadecane. PAH contamination caused shifts in the seawater microbial community-from a highly diverse one dominated by Alphaproteobacteria to less diverse communities dominated by Gammaproteobacteria. Furthermore, the combination of PAHs exerted a compounded negative influence on the microbial community, reducing its diversity and thus functional capacity of the ecosystem. These results advance our understanding of bacterial community dynamics in response to contrasting qualities of hydrocarbon contamination. This understanding is fundamental in the application and monitoring of bioremediation strategies if accidents involving oil spillages occur near Trindade Island and similar ecosystems.

• Klíčová slova
• Hydrocarbon biodegradation, Hydrocarbonoclastic bacteria, Metagenomics, Microbial ecology, Pristine environment, Trindade Island,
• MeSH
• alkany MeSH
• Alphaproteobacteria účinky léků   metabolismus   MeSH
• Bacteria klasifikace   účinky léků   genetika   metabolismus   MeSH
• biodegradace MeSH
• biodiverzita MeSH
• DNA bakterií genetika   MeSH
• ekosystém MeSH
• fenantreny metabolismus   MeSH
• Gammaproteobacteria účinky léků   metabolismus   MeSH
• látky znečišťující vodu MeSH
• metagenomika MeSH
• mikrobiální společenstva účinky léků   genetika   fyziologie   MeSH
• mořská voda mikrobiologie   MeSH
• ostrovy MeSH
• polycyklické aromatické uhlovodíky farmakologie   MeSH
• pyreny MeSH
• RNA ribozomální 16S metabolismus   MeSH
• uhlovodíky škodlivé účinky   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• znečištění ropou škodlivé účinky   MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Brazílie MeSH
• ostrovy MeSH
• Názvy látek
• alkany MeSH
• DNA bakterií MeSH
• fenantreny MeSH
• látky znečišťující vodu MeSH
• n-hexadecane MeSH Prohlížeč
• polycyklické aromatické uhlovodíky MeSH
• pyrene MeSH Prohlížeč
• pyreny MeSH
• RNA ribozomální 16S MeSH
• uhlovodíky MeSH

Mapping of hydrophobic organic compounds (HOCs) in surface seawater on an east-to-west transect of the South Atlantic Ocean (SAO) and across the Black Sea (BS) in 2016 was performed by a dynamic passive sampling device containing silicone-based passive samplers. In SAO as well as in BS the measurements confirmed freely dissolved concentrations of polychlorinated biphenyls, DDT and its metabolites, chlorobenzenes, cyclodiene pesticides, and brominated flame retardants in the range of units to low hundreds of pg per litre. The findings indicate that the spatial distribution of HOCs and emerging pollutants in the SAO and the BS is influenced by riverine inputs, ocean currents and atmospheric deposition from continental plumes. Observed concentration gradients indicate that eastern SAO receives DDT from sources in South Africa, whereas the emissions of endosulfan originate in South America. Elevated HOC concentrations in the northwestern BS are related to their discharge by rivers from the European continent.

• Klíčová slova
• Brominated flame retardants, Contamination, Free dissolved concentration, Marine pollution, Organochlorine pesticides, Passive sampling, Persistent organic pollutants, Polybrominated diphenyl ethers, Polychlorinated biphenyls, Seawater, Silicone,
• MeSH
• halogenované difenylethery analýza   MeSH
• monitorování životního prostředí MeSH
• mořská voda MeSH
• pesticidy * analýza   MeSH
• polychlorované bifenyly * analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Atlantský oceán MeSH
• Černé moře MeSH
• Jihoafrická republika MeSH
• Jižní Amerika MeSH
• Názvy látek
• halogenované difenylethery MeSH
• pesticidy * MeSH
• polychlorované bifenyly * MeSH

Substantial increases in cardiac output (CO), stroke volume (SV), and gastrointestinal blood flow are essential for euryhaline rainbow trout (Oncorhyncus mykiss) osmoregulation in seawater. However, the underlying hemodynamic mechanisms responsible for these changes are unknown. By examining a range of circulatory and cardiac morphological variables of seawater- and freshwater-acclimated rainbow trout, the present study revealed a significantly higher central venous pressure (CVP) in seawater-acclimated trout (~0.09 vs. -0.02 kPa). This serves to increase cardiac end-diastolic volume in seawater and explains the elevations in SV (~0.41 vs. 0.27 ml/kg) and CO (~21.5 vs. 14.2 ml·min-1·kg-1) when compared with trout in freshwater. Furthermore, these hemodynamic modifications coincided with a significant increase in the proportion of compact myocardium, which may be necessary to compensate for the increased wall tension associated with a larger stroke volume. Following a temperature increase from 10 to 16.5°C, both acclimation groups exhibited similar increases in heart rate (Q10 of ~2), but SV tended to decrease in seawater-acclimated trout despite the fact that CVP was maintained in both groups. This resulted in CO of seawater- and freshwater-acclimated trout stabilizing at a similar level after warming (~26 ml·min-1·kg-1). The consistently higher CVP of seawater-acclimated trout suggests that factors other than compromised cardiac filling constrained the SV and CO of these individuals at high temperatures. The present study highlights, for the first time, the complex interacting effects of temperature and water salinity on cardiovascular responses in a euryhaline fish species.

• Klíčová slova
• cardiac filling pressure, cardiovascular, circulation, osmoregulation, venous capacitance, venous tone,
• MeSH
• centrální žilní tlak fyziologie   MeSH
• minutový srdeční výdej fyziologie   MeSH
• mořská voda * MeSH
• Oncorhynchus mykiss fyziologie   MeSH
• osmoregulace fyziologie   MeSH
• remodelace komor fyziologie   MeSH
• tepový objem fyziologie   MeSH
• tolerance k soli fyziologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

By virtue of their compactness, long-term stability, minimal reagent consumption and robustness, miniaturized sequential injection instruments are well suited for automation of assays onboard research ships. However, in order to reach the sensitivity and limit of detection required for open-ocean determinations of trace elements, it is necessary to preconcentrate the analyte prior its derivatization and subsequent detection by fluorescence. In this work, a novel method for the determination of dissolved zinc (Zn) at subnanomolar levels in seawater is described. The proposed method combines, for the first time, automated matrix removal, extraction of the target element, and fluorescence detection within a miniaturized flow manifold, based on the Lab-On-Valve (LOV) concept. The key feature of the microfluidic manipulation of the sample is flow programming, designed to pass sample through a mini-column where the target analyte and other complexable cations are retained, while the seawater matrix is washed out. Next, zinc is eluted and merged with a Zn selective fluorescent probe (FluoZin-3) at the confluence point of the LOV central channel using two high-precision stepper motor driven pumps that are operated in concert. Finally, the thus formed Zn complex is transported to the LOV flow cell for selective fluorescence measurement. This work describes the characterization and optimization of the method including Solid Phase Extraction using the Toyopearl AF-Chelate-650M resin, and detailed assay protocol controlled by a commercially available software and instrument. The proposed method features a LOD of 0.02 nM, high precision (<3% at 0.1 and 2 nM Zn levels), an assay cycle of 13 min and a reagent consumption of 150 μL FluoZin-3 per sample, which makes the method highly suitable for oceanographic shipboard analysis. The accuracy of the method has been validated through the analysis of seawater reference standards and comparison with ICP-MS determinations on seawater samples collected in the upper 1300 m of the subtropical south Indian Ocean. This work confirms that integration of sample pretreatment with optical detection in the LOV format offers a widely applicable approach to trace analysis of seawater.

• Klíčová slova
• FluoZin-3, GEOTRACES, Lab-On-Valve, Oceanography, Trace analysis, Zn,
• MeSH
• extrakce na pevné fázi metody   MeSH
• fluorescenční barviva chemie   MeSH
• fluorescenční spektrometrie metody   MeSH
• limita detekce MeSH
• miniaturizace MeSH
• mořská voda chemie   MeSH
• polycyklické sloučeniny chemie   MeSH
• referenční standardy MeSH
• stopové prvky analýza   MeSH
• zinek analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fluorescenční barviva MeSH
• FluoZin-3 MeSH Prohlížeč
• polycyklické sloučeniny MeSH
• stopové prvky MeSH
• zinek MeSH

We report the levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in seawater and air, and the air-sea dynamics through diffusive exchange analysis in Fildes Bay, King George Island, Antarctica, between November 2019 and January 30, 2020. Hexachlorobenzene (HCB) was the most abundant compound in both air and seawater with concentrations around 39 ± 2.1 pg m-3 and 3.2 ± 2.4 pg L-1 respectively. The most abundant PCB congener was PCB 11, with a mean of 3.16 ± 3.7 pg m-3 in air and 2.0 ± 1.1 pg L-1 in seawater. The fugacity gradient estimated for the OCP compounds indicate a predominance of net atmospheric deposition for HCB, α-HCH, γ-HCH, 4,4'-DDT, 4,4'-DDE and close to equilibrium for the PeCB compound. The observed deposition of some OCs may be driven by high biodegradation rates and/or settling fluxes decreasing the concentration of these compounds in surface waters, which is supported by the capacity of microbial consortium to degrade some of these compounds. The estimated fugacity gradients for PCBs showed differences between congeners, with net volatilization predominating for PCB-9, a trend close to equilibrium for PCB congeners 11, 28, 52, 101, 118, 138, and 153, and deposition for PCB 180. Snow amplification may play an important role for less hydrophobic PCBs, with volatilization predominating after snow/glacier melting. As hydrophobicity increases, the biological pump decreases the concentration of PCBs in seawater, reversing the fugacity gradient to atmospheric deposition. This study highlights the potential impacts of climate change, through glacier retreat, on the biogeochemistry of POPs, remobilizing those compounds previously trapped within the cryosphere which in turn will transform the Antarctic cryosphere into a secondary source of the more volatile POPs in coastal areas, influenced by snow and ice melting.

• Klíčová slova
• Antarctica, Biodegradation, Human impacts, Legacy, POPs, Snow amplification,
• MeSH
• chlorované uhlovodíky * analýza   MeSH
• hexachlorbenzen analýza   MeSH
• látky znečišťující vzduch * analýza   MeSH
• monitorování životního prostředí MeSH
• mořská voda MeSH
• pesticidy * analýza   MeSH
• polychlorované bifenyly * analýza   MeSH
• zátoky MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Antarktida MeSH
• Názvy látek
• chlorované uhlovodíky * MeSH
• hexachlorbenzen MeSH
• látky znečišťující vzduch * MeSH
• pesticidy * MeSH
• polychlorované bifenyly * MeSH