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Rok 2019
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A Three-Step Approach to Estimation of Reduction Potentials of Natural Mixtures of Antioxidants Based on DPPH Test; Illustration for Catechins and Cocoa
PublikacjaThe aim of this study is to propose a methodology to assess electrochemical properties of complex mixtures of antioxidants, such as plant extracts, based on the results of simple and popular DPPH test. The first, most difficult step, involves determinations of standard reduction potentials (E0) for the series of purified compounds (here catechins). The next step is the calculation of stoichiometric values (n10) based on the results...
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Adsorption of Cr(VI) in aqueous solution using sago bark (Metroxylon sagu) as a new potential biosorbent
PublikacjaThis paper investigated the ability of sago bark (Metroxylon sagu) as a new potential biosorbent in removing Cr(VI) in batch system. The optimum adsorption capacity of sago bark (Metroxylon sagu) was 61.73 mg/g achieved at pH 3, agitation rate of 100 rpm, contact time 60 min, particle size ≤32 μm, and initial concentration of Cr(VI) 1,000 mg/L at room temperature (25°C). The adsorbent regeneration was carried out using 0.01 M HNO3...
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Aluminium in glacial meltwater demonstrates an association with nutrient export (Werenskiöldbreen, Svalbard)
PublikacjaThe aluminium (Al) cycle in glacierised basins has not received a great deal of attention in studies of biogeochemical cycles. As Almay be toxic for biota, it is important to investigate the processes leading to its release into the environment. It has not yet been ascertained whether filterable Al (passing through a pore size of 0.45 m) is incorporated into biogeochemical cycles in glacierised basins. Our study aims to determine...
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Analiza produktów degradacji emitowanych podczas regeneracji gumy
PublikacjaWyznaczenie profilu emisji oraz wytypowanie charakterystycznych związków chemicznych uwalnianych z powierzchni opracowanych materiałów polimerowych może stanowić jeden z elementów kontroli ich jakości. W pracy przedstawiono wyniki badań emisji związków chemicznych z grupy lotnych związków organicznych uwalnianych z odpadów gumowych podczas ich przetwórstwa przy użyciu współbieżnej wytłaczarki dwuślimakowej. Ponadto, przedstawiono...
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Analytical applications and physicochemical properties of ionic liquid-based hybrid materials: A review
PublikacjaIonic liquids with their unique properties found so far numerous analytical applications. Among them ionic liquids immobilized on the surface or within the pores of a solid support were successfully utilized in extraction techniques dedicated to preconcentration of the analytes from food, environmental and biological samples. In this review we focus on comprehensive summarizing of available literature data on the examples of ionic...
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Analytical chemistry with biosolvents
PublikacjaOne of the current trends in green analytical chemistry is the introduction of green solvents, some of which are biobased. At the same time, the development of the biorefinery concept has allowed more biochemicals to be obtained with increased efficiency and from a wider range of feedstocks. The first examples of the use of biosolvents in analytical applications included extractions performed with alcohols, esters, and terpenes....
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Analytical procedures for short chain chlorinated paraffins determination - How to make them greener?
PublikacjaThe aim of the following paper was to gather current scientific information about the analytical protocols dedicated to measuring the content level of short-chain chlorinated paraffins (SCCPs) in various types of environmental samples. Moreover, the data about the basic validation parameters of applied procedures for SCCPs determination are listed. The main issue which is highlighted in the paper is the possibility of the application...
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ANTIOXIDANT POWER SERIES (APS) AS A TOOL FOR RATIONAL DESIGN AND ASSESSMENT OF HEALTH PROMOTING PROPERTIES OF FUNCTONAL FOODS BASED ON ANTIOXIDANT PHYTOCHEMICALS
PublikacjaOver past decades, plantborne antioxidants dominated so called "translational research" in the area of food, nutrition, and disease prevention. Among consumers and producers, such phytochemicals are synonyms of nutriceuticals. Popularity and commercial success of antioxidants stems from mechanistic studies suggesting the involvement of reactive oxygen species in etiology of chronic diseases. However, epidemiology failed to provide...
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Antybiotyki aminoglikozydowe - problemy i wyzwania współczesnej analityki
PublikacjaZwiększające się zużycie produktów farmaceutycznych i ich przedostawanie się do środowiska naturalnego, jest jednym z istotnych problemów współczesnego świata. Legislacja dotycząca zawartości antybiotyków w środowisku naturalnym, żywności pochodzenia zwierzęcego, jak również w przypadku kontroli składu produktów farmaceutycznych ulega ciągłym zaostrzeniom. Stawia to przed analitykami coraz to nowe wyzwania polegające na opracowaniu...
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Application of GC-MS/MS technique for the determination of benzodiazepines in blood samples
PublikacjaAbstract Benzodiazepines (BZD) are widely used as pharmaceuticals in medicine. However, due to psychostimulatory effect of BZD, in the last decade, they are more and more often used as drugs of abuse. These compounds produce similar effects to classical illicit drugs and are sold as “legal” alternatives to them as new psychoactive substances (NPS). Currently new BZD, named designer benzodiazepines (DBZD), are synthesized each year...
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Application of ion chromatography with pulsed amperometric detection for the determination of trace cyanide in biological samples, including breast milk
PublikacjaCyanide (CN) is the biomarker of exposure to the components of tobacco smoke, although its presence in biological samples is also due to the consumption of products containing cyanogenic glycosides. In this work, we determine the concentration of the free cyanide in urine, saliva and breast milk matrices, using ion chromatography with pulsed amperometric detection (IC-PAD). IC-PAD is an emerging method, with only few documented...
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Application of ionic liquids in microextraction techniques: Current trends and future perspectives
PublikacjaIonic liquids (ILs) with their unique properties found so far numerous analytical applications. Among them ILs both in their liquid form and immobilized on the surface or within the pores of a solid support were successfully utilized in microextraction techniques. The scope of this review will cover a comprehensive summarizing of available literature data on selected properties of ILs playing a key role in analytical purposes,...
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Application of micellar electrokinetic chromatography for detection of silver nanoparticles released from wound dressing
PublikacjaThe recent emergence of nanotechnology has provided a new therapeutic modality in case of silver nanoparticles. Dressings containing silver form the basis for the treatment of burns and wounds, either acute or chronic ones. The aim of the study was to examine silver release from the different wound dressings: commercially available (Atrauman Ag, Aqua- cel Ag) and experimental (FKDP-AgNPs) using MEKC. In order to characterize prepared keratin...
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Application potential of dummy molecularly imprinted polymers as solidphase extraction sorbents for determination of low-mass polybrominated diphenyl ethers in soil and sediment samples
PublikacjaDespite the introduction of restrictive regulations in the USA and the European Union, polybrominated diphenyl ethers (PBDEs) are still found in various types of environmental and biological samples at significant concentration levels. The presence of these persistent organic pollutants in the environment raises important issues because of their negative impact on immunological and neurological systems, and on the hormonal balances...
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Assessment of the Bulgarian Wastewater Treatment Plants’ Impact on the Receiving Water Bodies
PublikacjaDeterioration of water quality is a major problem world widely according to many international non-governmental organizations (NGO). As one of the European Union (EU) countries, Bulgaria is also obliged by EU legislation to maintain best practices in assessing surface water quality and the efficiency of wastewater treatment processes. For these reasons studies were undertaken to utilize ecotoxicological (Microtox®, Phytotoxkit...
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Beneficial effects and potential risks of tomato consumption for human health: An overview
PublikacjaTomato and its derived products have a very interesting nutritional value in addition to prominent antioxidant,anti-inflammatory, and anticancer activities. In terms of tomatoes are generally quite safe to eat. However,overall consumption varies from individual to individual. Indeed, either beneficial or harmful effects of plantsor their derived products are closely related to quality, including the presence of biologically active...
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Biomarkers of alcohol consumption in body fluids - possibilities and limitations of application in toxicological analysis
PublikacjaEthyl alcohol is the most popular legal drug, but its excessive consumption causes social problems. Despite many public campaigns against alcohol use, car accidents, instances of aggressive behaviour, sexual assaults and deterioration in labor productivity caused by inebriated people is still commonplace. Fast and easy diagnosis of alcohol consumption is required in order to introduce proper and effective therapy, and is crucial...
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Biopsy needles coated with the antimicrobial coatings
PublikacjaDrug delivery systems are used to achieve higher therapeutic effects of medicaments in a specific diseased site with minimal toxicological effect. The used of biopolymers in drug delivery systems ensure the biocompatibility, biodegradability and low immunogenicity. Drug delivery systems enhance the drug delivery actively and can be used in different diseases. In this study, two types of polymer coatings were prepared and were...
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Bisphenols (A, S, and F) affect the basic hormonal activity determined for pharmaceuticals – Study of Saccharomyces cerevisiae
PublikacjaPharmaceuticals and analogs of bisphenol A (BPA) are increasingly threatening environmental pollutants. In this study, mixtures of selected pharmaceuticals (diclofenac sodium salt, chloramphenicol, oxytetracycline hydrochloride, fluoxetine hydrochloride, estrone, ketoprofen, progesterone, gemfibrozil and androstenedione) were prepared with BPA and its two analogs (namely, bisphenols F and S) at such ratios to reflect environmentally...
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Calculating the Partition Coefficients of Organic Solvents in Octanol/Water and Octanol/Air
PublikacjaPartition coefficients define how a solute is distributed between two immiscible phases at equilibrium. The experimental estimation of partition coefficients in a complex system can be an expensive, difficult, and time-consuming process. Here a computational strategy to predict the distributions of a set of solutes in two relevant phase equilibria is presented. The octanol/water and octanol/air partition coefficients are predicted...
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Chemical variability of Rhododendron tomentosum (Ledum palustre) essential oils and their pro-apoptotic effect on lymphocytes and rheumatoid arthritis synoviocytes
PublikacjaRhododendron tomentosum (Ledum palustre) is an aromatic plant traditionally used for alleviating rheumatic complaints which makes it a potential candidate for a natural drug in rheumatoid arthritis (RA) treatment. However, the effects of plants’ volatiles on apoptosis of synovial fibroblasts and infiltrating leucocytes of RA synovia, have not been reported. Volatile fraction of R. tomentosum is chemically variable and chemotypes...
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Chemometrics and Statistics | Multicriteria Decision Making
PublikacjaThis contribution describes the application of Multicriteria Decision Making tools in analytical chemistry. The general scheme of MCDM is presented to show its general steps. The most frequently applied in analytical sciences MCDM techniques – AHP, ELECTRE, PROMETHEE and TOPSIS – are briefly described and their advantages and disadvantages are discussed. The applications in analytical chemistry are selection of an appropriate...
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Chromatgrafia cieczowa. Teoria i praktyka
PublikacjaKsiążka zawiera całokształt wiedzy dotyczącej chromatografii ciecvzowej - kolumnowej i cienkowarstwowej. Opisane zostały wszystkie techniki chromatografii cieczowej, zarówno w zakresie teorii chromatografii, jak i praktycznych zastosowań.
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Ciecze jonowe jako medium sorpcyjne w mikroekstrakcji do pojedynczej kropli Cz. I. Podstawy teoretyczne zagadnienia
PublikacjaTechnika mikroekstrakcji do pojedynczej kropli stanowi sztandarowy przykład rozwiązania technicznego spełniającego wymogi stawiane przez ideę zielonej chemii analitycznej.
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Ciecze jonowe jako medium sorpcyjne w mikroekstrakcji do pojedynczej kropli. Cz.II. Praktyka analityczna
PublikacjaPomimo rosnącego zainteresowania metodami analitycznymi opartymi na użyciu cieczy jonowych ich sprzężenie wraz z techniką mikroekstrakcji do pojedynczej kropli nie osiągnęło zadowalającej popularności oraz akceptacji ze strony środowiska naukowego.
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Comparative Greenness Evaluation
PublikacjaGreenness of analytical procedure is multivariable aspect as many greenness criteria should be taken into consideration. On the other hand, modern analytical chemistry offers dozens of analytical procedures, based on different sample preparation and final determination techniques that are used for the determination of a given analyte in a given matrix. For such complex decision-making processes, multi-criteria decision analysis...
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Comparison of GC–MS and MEKC methods for caffeine determination in preworkout supplements
PublikacjaIn this study, GC–MS- and MEKC-based methods for determination of caffeine (CAF) in preworkout supplements were developed and validated. The proposed protocols utilized minimal sample preparation (simple dilution and syringe filtration). The developed methods achieved satisfactory validation parameters, i.e. good linearity (R2 0.9988 and R2 0.9985 for GC–MS- and MEKC-based method, respectively), satisfactory intraand interaccuracy...
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Comparison of Redox Properties of Flavonoid Aglycones and Corresponding Glycosides and Their Mixtures in the Cellular Model
PublikacjaFlavonoids are polyphenolic compounds commonly found in plants. As dietary components, they have been shown to exhibit numerous pro-health properties that are believed to be associated with their antioxidant effects. In this study, the antioxidant activity of four flavonoid compounds was determined by cellular antioxidant activity assay using HT29 cells as a model of the alimentary tract. The strongest impact on cellular redox...
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Concentration levels of selected analytes in the gas phase of an e-cigarette aerosol
PublikacjaThe aerosols generated from e-cigarettes are composed of liquid and gas phases resulting from vapourized e-liquid. The apportioning of substances from e-liquid into the liquid and gas phases during e-cigarette use has not been extensively studied. Partitioning of e-liquid components between the gas and the liquid phase of the aerosol influences the substances inhaled and exhaled by the users, leading to second-hand exposure. It...
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Concentrations and loads of DOC, phenols and aldehydes in a proglacial arctic river in relation to hydro-meteorological conditions. A case study from the southern margin of the Bellsund Fjord – SW Spitsbergen
PublikacjaClimate warming accelerates the melting and thawing of cryosphere components. Therefore, it favours the release of contaminants stored in High-Arctic glaciers for many years. The rate of land-based glacier retreat is of particular importance for the hydrological regime of glacial rivers, but also for the chemical composition of their waters. In this study, we examined 84 surface water samples collected during a period of 42 days...
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Determination and identification of organic acids in wine samples. Problems and challenges.
PublikacjaFor long time, organic acids were underestimated. However, during last two decades there is an increasing interest of natural compounds having antioxidant, antimicrobial and anti-inflammatory properties thus organic acids are very preferable. Wine stands as one of the sources of organic acids since they are responsible for its organoleptic and aestethic character. Nevertheless, it is important to not exceed acceptable level of...
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Determination of Antioxidant Activity of Vitamin C by Voltammetric Methods
PublikacjaVoltammetric methods—cyclic (CV) and differential pulse voltammetry (DPV) are considered the most appropriate way to evaluate antioxidant activity of redox active compounds. They provide information about both mechanism and kinetics of electrochemical oxidation of antioxidants as well as their physical and chemical properties such as the redox potential or the number of electrons transferred. These methods are helpful for understanding...
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Determination of free tyrosine in equestrian supplements by LC–MS/MS and comparison of its quantity with total free amino acids content in view of doping control
PublikacjaThe reports on the probable beneficial impact of tyrosine (TYR) supplementation on performance enhancement have contributed to the growth of interest in TYR in equestrian sports field and related industries, such as the manufacture of dietary and nutritional supplements. In this study, the first attempt to the assessment of horses exposure to TYR during nutritional supplementation was demonstrated by quantification of unbound TYR...
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Determination of heavy metals in eyeshadows from China
PublikacjaPersonal care products and cosmetics are used daily by many people, causing local exposure to certain chemical substances through the application directly inside the oral cavity, on the skin, lips, eyes, and mucosa. Eyeshadows are among the most commonly used types of cosmetics. According to scientifc reports, they may contain heavy metals, especially in non-original products. The exposure to said heavy metals may cause local skin...
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Determination of polycyclic aromatic hydrocarbons (PAHs) and other organic pollutants in freshwaters on the western shore of Admiralty Bay (King George Island, Maritime Antarctica).
PublikacjaOrganic 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...
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Determination of selected parameters/ analytes in surface water samples collected in the surroundings of the capital of Spitsbergen (Longyearbyen)
PublikacjaPolar regions are extremely sensitive to pollution such as harmful gases, particles or toxic substances which affect the Arctic climate and ecosystems. Spitsbergen, as well as all Arctic region, because of its geographically distant location and lack of industry sector, should be free of chemical pollution. Despite this, many pollutants could be found in the Polar environment, for example in freshwaters. Their occurrence is related...
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Dietary antioxidants as a source of hydrogen peroxide
PublikacjaStudies of 54 antioxidants revealed that 27 of them, mainly polyphenols, generated hydrogen peroxide (H2O2) when added to Dulbecco’s modified Eagle’s medium (DMEM), other media used for culture of mammalian and yeast cells and phosphate-buffered saline. The most active antioxidants were: propyl gallate (PG), (−)-epigallocatechin gallate (EGCG) and quercetin (Q). Chelex treatment and iron chelators decreased H2O2 generation suggesting...
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Diethyl carbonate as a green extraction solvent for chlorophenol determination with dispersive liquid–liquid microextraction
PublikacjaThe principles of green analytical chemistry indicate that the search for greener organic solvents for extraction applications is crucial. In this study diethyl carbonate (DEC) is proved to be a green solvent, as it is relatively nontoxic, obtainable from renewable resources and biodegradable. Here it is applied as an extraction solvent for chlorophenol determination in water samples with dispersive liquid–liquid microextraction....
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Differences between selected volatile aromatic compound concentrations in sludge samples in various steps of wastewater treatment plant operations
PublikacjaSewage sludge, one of the main wastes generated during wastewater treatment, constitutes an important source of emissions of volatile chemical compounds such as volatile aromatic compounds These substances may undergo various changes as a result of operations and unit processes, which affects their concentrations in sewage sludge. An important factor determining the potential hazardousness of volatile organic compounds is the quality...
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Dispersive liquid-liquid microextraction combined with gas chromatography–mass spectrometry for in situ determination of biogenic amines in meat: Estimation of meat's freshness
PublikacjaA dispersive liquid-liquid microextraction (DLLME) gas chromatography–mass spectrometry (GC–MS) technique was developed for the determination of selected biogenic amines (BAs) in samples of poultry, pork and beef. Prior to the extraction process, an appropriate volume of sodium hydroxide solution was added to each of the portioned samples. Next, samples were homogenized, centrifuged and finally sonicated at an increased temperature....
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DNA Methylation Changes Induced by Redox-Active Compounds—Choosing the Right PCR-Based Method
PublikacjaThe impact of catechins on the expression profile of redox-related genes in HT29 cell line has been studied recently by our group using Oxidative Stress RT2 Profiler PCR Array. Within the examined panel of 84 genes, the down-regulation of SRXN1 gene was unique among other up-regulated genes. We hypothesized that the observed down-regulation resulted from DNA methylation and have exploited this observation to choose the proper strategy...
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Dynamiczna technika analizy fazy nadpowierzchniowej
PublikacjaDążność do uzyskiwania miarodajnej informacji analitycznej na temat rodzaju oraz ilości związków chemicznych emitowanych z powierzchni materiałów polimerowych stanowi istotny czynnik w procesie rozwoju technik analitycznych, jako nieodzowny element kontroli jakości opracowywanych materiałów użytkowych. W pracy naświetlono najważniejsze informacje na temat rozwiązań konstrukcyjnych i aparaturowych zaliczanych do dynamicznych technik...
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Electronic Noses in Medical Diagnostics
PublikacjaElectronic nose technology is being developed in order to identify aromas in a way parallel to the biologic olfaction. When applied to the field of medicine, such device should be able to identify and discriminate between different diseases. In recent years this kind of approach finds application in medical diagnostics, and especially in disease screening. Despite the fact that devices utilizing chemical sensor arrays are not routinely...
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Environmental characteristics of a tundra river system in Svalbard. Part 1: Bacterial abundance, community structure and nutrient levels
PublikacjaThe Arctic hosts a set of unique ecosystems, characterised by extreme environmental conditions and undergoing a rapid change resulting from the average temperature rising. We present a study on an aquatic ecosystem of the Revelva catchment (Spitsbergen), based on samples collected from the lake, river and their tributaries, in the summer of 2016. The landscape variety of the study site and the seasonal change in the hydrological...
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Environmental characteristics of a tundra river system in Svalbard. Part 2: Chemical stress factors
PublikacjaBacterial communities in the Arctic environment are subject to multiple stress factors, including contaminants, although typically their concentrations are small. The Arctic contamination research has focused on persistent organic pollutants (POPs) because they are bioaccumulative, resistant to degradation and toxic for all organisms. Pollutants have entered the Arctic predominantly by atmospheric and oceanic long-range transport,...
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Evaluation of Health Hazard Due to Emission of Volatile Organic Compounds from Various Processing Units of Wastewater Treatment Plant
PublikacjaThe paper describes an attempt at health risk assessment and odour concentration determination in the most important units of a wastewater treatment plant. The cancer risk (CR) and hazard index (HI) parameters in selected measurement locations were calculated based on the results of chromatographic analyses (GCxGC-TOF-MS) and the United States Environmental Protection Agency (US EPA) guidelines. No exceedance of the CR and HI acceptable...
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Evaluation of the influence of grapevine growing conditions on wine quality
PublikacjaScientists are increasingly interested in the viticulture concept of terroir, which states that unique properties of wine are strictly related to the environmental conditions under which grapes are cultivated. The aim of the research was to compare the parameters characterizing wines produced in Poland, such as pH, conductivity, total organic carbon (TOC), and concentration of anions (F−, Cl−, NO2−, NO3−, PO43−, SO42−). It was...
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Evaluation of the use of reindeer droppings for monitoring essential and non-essential elements in the polar terrestrial environment
PublikacjaExcess or toxic metals, non-metals and metalloids can be eliminated from the organism by deposition in inert tissue (e.g. fur) or excretion with body secretions, urine and faeces. Droppings are one of the main routes for the elimination of multiple elements and they can be collected without direct contact with the animal. Contaminant concentration has been examined in non-lethally collected tissues of several species (especially...
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Examination of fresh water chemistry in maritime Antarctica during austral summer 2017
PublikacjaDue to the fact that Antarctica is one of the least polluted places on Earth, it is a perfect place to observe the spread of global pollution. Therefore, research conducted on this continent is important due to the possibility of investigating the type of pollution and their way of transport. This work considers presence of organic contaminants in Maritime Antarctica in unexplored until now, Lions Rump headland. Qualitative and...
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FROM HARVESTING TO DISTILLATION - EFFECT OF ANALYTICAL PROCEDURES ON THE YIELD AND CHEMICAL COMPOSITION OF RHODODENDRON TOMENTOSUM (LEDUM PALUSTRE) ESSENTIAL OIL
PublikacjaRhododendron tomentosum possesses the anti-inflammatory, analgesic and antimicrobial properties, determined by the chemical composition of its essential oil. The effects of place (Miszewko, Lubichowo) and time of harvesting (June, November) as well as drying (air-drying, oven-drying, freeze-drying) and isolation (in Deryng, Clevenger and Likens-Nickerson apparatus) procedures on the yield and quality of R. tomentosum essential...