Papers by Branislav Vrana
Passive samplers (PSs) can be valuable tools as complementary method in monitoring water quality ... more Passive samplers (PSs) can be valuable tools as complementary method in monitoring water quality in the context of the WFD. Nevertheless, there is still a lack of quality assurance and control (QA/QC) procedures that demonstrate the reliability and the comparability of results obtained by passive sampling. The objective was to assess the potential function and the efficiency of PSs for monitoring pesticides in surface and coastal waters in the context of the WFD.
Introduction 33 2.2 The context: why develop passive air sampling techniques for POPS? 35 2.3 Wha... more Introduction 33 2.2 The context: why develop passive air sampling techniques for POPS? 35 2.3 What approaches can be used? 38 2.4 The choice of sampler designs: features, advantages and potential problems 40 2.4.1 Low-capacity sampling: polymer-coated glass 42 2.4.2 Medium-capacity sampling devices: polyurethane foam disks 43 2.4.3 High-capacity sampling devices: semipermeable membrane devices and XAD-2 resin 44 xv Contents
Journal of Environmental Science and Health Part a Toxic Hazardous Substances Environmental Engineering, Feb 18, 2011
The mechanism of biphenyl biodegradation by Pseudomonas stutzeri was studied. Growth curves on bi... more The mechanism of biphenyl biodegradation by Pseudomonas stutzeri was studied. Growth curves on biphenyl were measured, along with dissolution kinetics of biphenyl and production of biosurfactants by the bacterium. Biphenyl was supplied as pure crystals (the crystal biphenyl), adsorbed to Chromosorb G (the Chromosorb G biphenyl) or XAD-4 particles (the XAD-4 biphenyl). No lag phase was observed on the crystal biphenyl, while this period lasted 3.5-6.0 hours on the Chromosorb G biphenyl. The linear specific growth rates (LSGRs) ranged from 2.00 × 10(-4) to 293 × 10(-4) dry weight grams/L/h (d.w.g/L/h) on these two substrates. The LSGR values were directly proportional to the interfacial area between the solid substrate and the microbial suspension. The XAD-4 biphenyl was not bioavailable to the bacterium. The zero-order rates of dissolution ranged from 2.3 × 10(-5)to 8.0 × 10(-4) g/L/h on the crystal biphenyl and the Chromosorb G biphenyl. No biosurfactant production was observed on any biphenyl substrate. Growth curves, results of dissolution measurements and the scanning electron microscope (SEM) images indicate that Pseudomonas stutzeri takes up biphenyl from the aqueous phase as well as the solid phase of the crystal and the Chromosorb G biphenyl. The mechanism of uptake depends on the initial biphenyl concentration and the particle diameter of the biphenyl substrate.
TrAC Trends in Analytical Chemistry, 2016
Highlights A collaborative trial was performed to assess the variability of passive sampling. ... more Highlights A collaborative trial was performed to assess the variability of passive sampling. The passive sampling process does not cause excessive data variability. Unsatisfactory accuracy of sampler analysis was the main source of variability. Translation from passive sampler to water concentration increases the variability. In future passive sampling and laboratory analysis should be assessed separately.
Environmental science and pollution research international, Jan 25, 2015
Near-ground air (26 substances) and surface seawater (55 substances) concentrations of persistent... more Near-ground air (26 substances) and surface seawater (55 substances) concentrations of persistent toxic substances (PTS) were determined in July 2012 in a coordinated and coherent way around the Aegean Sea based on passive air (10 sites in 5 areas) and water (4 sites in 2 areas) sampling. The direction of air-sea exchange was determined for 18 PTS. Identical samplers were deployed at all sites and were analysed at one laboratory. hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs) as well as dichlorodiphenyltrichloroethane (DDT) and its degradation products are evenly distributed in the air of the whole region. Air concentrations of p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and o,p'-DDT and seawater concentrations of p,p'-DDE and p,p'-DDD were elevated in Thermaikos Gulf, northwestern Aegean Sea. The polychlorinated biphenyl (PCB) congener pattern in air is identical throughout the region, while polybrominated diphenylether (PBDE)patterns are obviously ...
Chemosphere, 1981
Abstract In recognition of the need to estimate biosorption for natural microbial populations, th... more Abstract In recognition of the need to estimate biosorption for natural microbial populations, the variability of partition coefficients for two hydrophobic pollutants to natural populations from a variety of aquatic systems was investigated. Biosorption partition coefficents for ...
In the last five years we have used semipermeable membrane devices (SPMDs) in several field campa... more In the last five years we have used semipermeable membrane devices (SPMDs) in several field campaigns for time-integrative and biomimetic sampling of persistent organic micropollutants (chlorinated hydrocarbons, polycyclic aromatics, etc.) in brooks, rivers, lakes and groundwater wells around Leipzig. These devices are expensive and their processing is time-and solvent-consuming. Therefore we have developed novel types of passive samplers consisting of a membrane which encloses coarse silicone material or polydimethylsiloxane (PDMS) coatings (embedded in a fluid) as the collecting phase. We tested different commercially available materials like 100 µm PDMS fibres from Supelco, Twister bars from Gerstel, silicone tubes and rods from Goodfellow. Also different fluid compositions in the membrane bag were tested. In laboratory flow-through experiments we determined the sampling rates with different sampler types under standard conditions. Preliminary field trials have shown the applicability of the new samplers but have also indicated necessary improvements concerning especially the membrane enclosure used. The general advantages of the new developed passive samplers are i) the simple removing of the collector phase; ii) its processing without further clean-up steps by direct thermodesorption or solvent microextraction; iii) the possibility to spike the collecting phase before deployment with so-called performance reference compounds and iv) that, in addition to chemical target or non-target analysis, the collecting phase can also be subject to biological effect screening (after digestion using an appropriate solvent). Provided further field tests succeed, some of the new samplers will be inexpensive and multifunctional alternatives to established passive samplers (SPMDs, dosimeters) for monitoring persistent (more hydrophobic) organic compounds in aqueous environmental compartments.
Environmental Science and Pollution Research
Triolein-containing semipermeable membrane devices (SPMDs) were employed as passive samplers to p... more Triolein-containing semipermeable membrane devices (SPMDs) were employed as passive samplers to provide data on the bioavailable fraction of organic, waterborne, organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polynuclear aromatic hydrocarbons (PAHs) in streams flowing through a highly polluted industrial area of Bitterfeld in Saxony-Anhalt, Germany. The contamination of the region with organic pollutants originates in wastewater effluents from the chemical industry, from over one-hundred years of lignite exploitation, and from chemical waste dumps. The main objective was to characterise time-integrated levels of dissolved contaminants, to use them for identification of spatial trends of contamination, and their relationship to potential pollution sources. SPMDs were deployed for 43 days in the summer of 1998 at four sampling sites. The total concentration of pollutants at sampling sites was found to range from a low of 0.8 microgram/SPMD to 25 micrograms/SPMD for PAHs, and from 0.4 microgram/SPMD to 22 micrograms/SPMD for OCPs, respectively. None of the selected PCB congeners was present at quantifiable levels at any sampling site. A point source of water pollution with OCPs and PAHs was identified in the river system considering the total contaminant concentrations and the distribution of individual compounds accumulated by SPMDs at different sampling sites. SPMD-data was also used to estimate average ambient water concentrations of the contaminants at each field site and compared with concentrations measured in bulk water extracts. The truly dissolved or bioavailable portion of contaminants at different sampling sites ranged from 4% to 86% for the PAHs, and from 8% to 18% for the OCPs included in the estimation. The fraction of individual compounds found in the freely dissolved form can be attributed to the range of their hydrophobicity. In comparison with liquid/liquid extraction of water samples, the SPMD method is more suitable for an assessment of the background concentrations of hydrophobic organic contaminants because of substantially lower method quantification limits. Moreover, contaminant residues sequestered by the SPMDs represent an estimation of the dissolved or readily bioavailable concentration of hydrophobic contaminants in water, which is not provided by most analytical approaches.
Organic pollutants are often present in the water column at trace concentrations that are difficu... more Organic pollutants are often present in the water column at trace concentrations that are difficult to detect when conventional low volume spot sampling of water is applied. The scope of the sampling campaign performed using passive samplers was the screening of trace organic pollutants and their toxic potentials in the water column of the Danube, as well as the assessment of their spatial distribution along the river. Freely dissolved concentrations of priority substances in the water phase (cfree) can be derived from the uptake of these substances by passive samplers, and because accumulated contaminants represent a large water volume, low limits of quantification can be obtained. Cfree is a more stable parameter than a concentration measured in whole water as the level is not influenced by variable amounts of the substance bound to dissolved and suspended particulate organic matter. Thus, it is very suitable for assessment of trends. Cfree is further considered to play a key role...
Journal of Environmental Monitoring, 2010
Passive sampling devices are increasingly relied upon for monitoring non-polar organic contaminan... more Passive sampling devices are increasingly relied upon for monitoring non-polar organic contaminants in water. While many types of devices are available they have seldom been evaluated alongside each other. We tested six passive sampling devices namely: Chemcatcher, two modified versions of the membrane enclosed sorptive coating (MESCO I (m) and MESCO II), silicone rod and strip and semipermeable membrane device (SPMD). Samplers spiked with a range of performance reference compounds (PRCs) were exposed (5 days) in a continuous flow-through tank using Meuse river water fortified with fluctuating concentrations (20-700 ng L(-1)) of polycyclic aromatic hydrocarbons, polychlorinated biphenyls, hexachlorobenzene and p,p'-DDE. Dissipation rates of PRCs appeared to provide reliable information on exchange kinetics even under these short-term exposure conditions. They accounted for differences between masses of contaminants accumulated by replicate samplers, indicating that the variability between replicates was in part due to differences in water turbulences and hence boundary layer thickness. In this system, resistances in the membrane and boundary layers are likely to be in the same order of magnitude for PRCs. Sampler performance was evaluated by comparing masses accumulated in the devices only for analytes for which uptake was linear (integrative) and limited by transport across the boundary layer. Consistent data were obtained across the range of samplers despite their different configurations, and the analysis being conducted in three separate laboratories. The pattern in analyte masses accumulated by Chemcatcher and MESCO II data could be explained by the extraction and analysis being conducted only on the receiving phase of the samplers and a significant impact of the lag-phase prior to obtaining a steady flux of contaminants across the polyethylene membranes.
The Utilization of Bioremediation to Reduce Soil Contamination: Problems and Solutions, 2003
Comprehensive Analytical Chemistry, 2007
Acta Chimica Slovaca, 2013
Journal of Soils and Sediments, 2014
ABSTRACT Purpose A multi-compartment monitoring study was performed to characterize the effect of... more ABSTRACT Purpose A multi-compartment monitoring study was performed to characterize the effect of environmental variables, such as temperature and water flow as well as sediment characteristics, on the distribution and transport of persistent organic pollutants (POPs) in a dynamic river system during 1 year in an industrial region in central Europe. Materials and methods Waterborne polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed over a period of 1 year at five sampling sites in the Morava River in the Czech Republic. Contaminants were measured monthly in riverbed sediments, freshly deposited sediments, water samples and passive samplers. Results and discussion Sediments are the main carrier of POPs in the river. Distinguishable patterns of PAHs, OCPs and PCBs in sediment indicate that their origin is from distinct sources and different transport pathways. The PAHs were identified as the dominant contaminant group of compounds with a mean concentration in sediment of 5,900 μg kg−1. Such concentrations are up to 10 times higher than in the Danube River, into which Morava drains. In contrast, mean concentrations of PCBs, hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethane and its breakdown products (DDTs) and hexachlorobenzene (HCB) of 6.0, 0.4, 4.2 and 6.0 μg kg1, respectively, are similar to those in the Danube. With some exceptions, no significant difference in composition of surficial riverbed sediments and those collected using sediment traps was observed. Despite the presence of potential local pollutant sources, the differences in contaminant concentrations between sites in the region were in most cases not significant. Variations in POP concentrations in sediments are mainly induced by high flow events, whereas seasonal variability was not observed. Conclusions The changes in contaminant concentrations in Morava River sediments are induced by episodic high flow events that cause erosion of contaminant-containing particles and their deposition at suitable downstream sites.
Water Science & Technology, 2011
The European legislation, and in particular the Water Framework Directive requires the developmen... more The European legislation, and in particular the Water Framework Directive requires the development of cost efficient monitoring tools that can provide the required information for the assessment of water contamination. Passive sampling methods represent one of the novel tools that have a potential to be used in various regulatory monitoring programmes aimed at assessing the levels of chemical pollutants. These methods are particularly interesting for sampling polar organic pollutants in water because they provide representative information of the water quality over extended time periods (days to weeks) in environments with fluctuating contaminant concentrations. This is achieved by integrative sampling of pollutants over the whole sampler deployment period. These tools can be coupled to toxicity testing using bioassays that give information on toxic and ecotoxic hazards associated to substances that are present, these substances being identified or not. In this study the polar organic chemical integrative sampler (POCIS) was used in surface water to evaluate the water contamination by polar organic compounds and their potential toxicity.
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Papers by Branislav Vrana