Survey of Appearance and temporal concentrations of polar organic pollutants in Saxon waters.

Integrative passive samplers such as the Chemcatcher are often proposed as alternatives for conventional grab sampling of surface waters. So far, their routine application for regulatory monitoring is hampered (among others) by the fact that TWA concentrations may depend significantly on the design and specifics of the samplers employed. The presented study addresses this issue, focusing on the uptake of polar organic pollutants in three different Chemcatcher configurations and polydimethylsiloxane (PDMS) sheets in the field. Covering waste water treatment plant effluents, creeks, and rivers, samplers were deployed for periods of 14-21 days in eight trials over the course of one year. 33 organic pesticides, 14 transformation products and 31 pharmaceuticals could be detected at least once in TWA concentrations ranging from 0.03 ng/L to 16.5 µg/L. We show that through employing generic, i.e. sampler specific, rather than compound specific sampling rates, the variation among results from three integrative passive sampler designs yields linear correlations with an offset of less than 0.1 and correlation coefficients r2 > 0.8. In this way, TWA concentrations enable the identification of low-concentration xenobiotics of concern, which may support regulatory monitoring correspondingly.

Passive sampling of herbicides above sediments at sites with losses of submerged macrophytes in a mesotrophic lake.

Declines of submerged macrophytes (SUM) were monitored in littoral zones of the deep, mesotrophic lake Suhrer See (Northern Germany) since 2017. Drastic losses coincided with intense agriculture in sandy sub-catchments and precipitation. All lines of evidence pointed to a causal connection with subsurface discharge indicating that herbicide application might have caused the effects. Passive sampling was applied in 2022 to elucidate, whether herbicides were really present at sites of losses and if so, in ecotoxicological relevant concentrations. Samplers were exposed on top of lake sediments in 2 m depth and under worst case conditions, i.e., at sites, known for losses of the whole functional group of SUM and at the beginning of the vegetation period. At this time, SUM diaspores were most vulnerable to repression of development and the subsurface discharge was high in the same instance. The potential ecotoxicological relevance of detected herbicide concentrations was assessed with a toxic units (TU) approach, with reference to acute effect concentrations (EC50 of green algae, 72 h, growth). The TU ranged from 0.001 to 0.03. Most concentrations exceeded the threshold of relevance set by an assessment factor of 1000, i.e., TU > 0.001. Locally applied herbicides acted by suppressing developmental stages, and the sum of TU exceeded 0.02 at all sites, mainly due to diflufenican. Not applied locally, terbuthylazine and its relevant metabolites, including terbutryn, acted by inhibiting photosynthesis, and the sum of TU reached 0.005. On this base, diflufenican was assessed to be likely a main stressor, all other detected herbicides to be potentially relevant. Uncertainties and knowledge gaps were specified. The result of the chemical risk assessment was counterchecked for consistence with biological monitoring data within a whole lake perspective. Concepts of empirical and advanced causal attribution methodology were applied to get a grip to the ecological causal field and to protection.

226Ra measurement via gamma-ray spectrometry of 222Rn progeny - quantification of radon losses from sample capsules.

Radium-226 detection in sediment samples is generally executed by means of gamma-ray spectrometry. Data evaluation relies (besides the 186.2 keV 226Ra gamma peak) on the combined analysis of major gamma peaks that are produced by the short-lived radon (222Rn) daughters 214Pb and 214Bi. Precondition for this detection approach is equilibrium decay of all members of the decay chain between 226Ra and 214Bi. In closed systems, this equilibrium is reached after about five half-lives of 222Rn (19 days). However, a closed system can only be guaranteed if the capsule which contains the sample prevents diffusive escape of radon. Such radon-tightness cannot be guaranteed for a wide range of plastic materials. Due to its polymer structure, plastic material generally tends to allow radon diffusion and hence radon loss from the sample resulting in a disturbance of the required decay equilibrium. The paper introduces an approach that allows quantifying radon loss from sample capsules by direct radon measurements using mobile radon detection equipment. The experimental findings are supported by theoretical considerations. An examined alternative approach based on the offset of the 186.2 keV data point from an efficiency function that is calculated exclusively from short-lived radon progeny peaks in the gamma-ray spectrum did not prove to be applicable due to a lack of supporting peaks in the low-energy section of the spectrum.

Calibration of the Chemcatcher® passive sampler and derivation of generic sampling rates for a broad application in monitoring of surface waters.

We determined sampling rates for 34 pesticides, five pesticide transformation products, and 34 pharmaceutical compounds with the Chemcatcher (CC) passive sampler in a laboratory-based continuous-flow system at 40 cm/s and ambient temperature. Three different sampling phases were used: styrene divinylbenzene disks (SDB-XC), styrene divinylbenzene reversed phase sulfonate disks (SDB-RPS), and hydrophilic lipophilic balance disks (HLB), in all cases covered with a diffusion-limiting polyethersulfone membrane. The measured sampling rates range from 0.007 L/d to 0.193 L/d for CC with SDB-XC (CC-XC), from 0.055 L/d to 0.796 L/d for CC with SDB-RPS (CC-RPS), and from 0.018 L/d to 0.073 L/d for CC equipped with HLB (CC-HLB). Comparison with sampling rates from literature enabled to derive generic sampling rates that can be used for compounds with unknown uptake kinetics such as transformations products and new compounds of interest. Field trial results demonstrate that the presently derived generic sampling rates are suitable for estimating time-weighted average concentrations within reasonable uncertainty limits. In this way, Chemcatcher passive sampling can be applied approximately to a broad range of solutes without the need for deriving compound-specific sampling rates, which enable compliance checks against environmental quality standards and further risk assessment.

Exploring the partitioning of hydrophobic organic compounds between water, suspended particulate matter and diverse fish species in a German river ecosystem.

Background: Bioaccumulation of hydrophobic organic compounds (HOCs) along freshwater food chains is a major environmental concern as top predators in food webs are relevant for human consumption. To characterize and manage the associated risks, considerable numbers of organisms are sampled regularly for monitoring purposes. However, ethical and financial issues call for an alternative, more generic and more robust approach for assessing the internal exposure of fish that circumvents large variability in biota sampling due to interindividual differences. Passive sampling devices (PSDs) offer a fugacity-based approach for pollutant enrichment from different abiotic environmental compartments with a subsequent estimation of bioaccumulation in fish which we explored and compared to HOC concentrations in fish as determined using traditional approaches. Results: In this study, concentrations in silicone-based PSDs applied to the water phase and suspended particulate matter (SPM) of a river polluted with HOCs were used to estimate the concentration in model lipids at thermodynamic equilibrium with either environmental compartment. For comparison, muscle tissue of seven fish species (trophic level 1.8 to 2.8) was extracted using traditional exhaustive solvent extraction, and the lipid-normalized concentrations of HOCs were determined. The PSD-based data from SPM proved to be a more conservative estimator for HOCs accumulated in fish than those from water. Body length of the fish was found to be more suitable to describe increasing accumulation of HOCs than their trophic level as derived from stable isotope analysis and might offer a suitable alternative for future studies. Conclusions: By combining fugacity-based sampling in the abiotic environment, translation into corresponding concentrations in model lipids and body length as an indicator for increasing bioaccumulation in fish, we present a suggestion for a robust approach that may be a meaningful addition to conventional monitoring methods. This approach potentially increases the efficiency of existing monitoring programs without the need to regularly sacrifice vertebrate species. Supplementary Information: The online version contains supplementary material available at 10.1186/s12302-022-00644-w.

Complex chemical cocktail, containing insecticides diazinon and permethrin, drives acute toxicity to crustaceans in mountain lakes.

Mountain lakes have long been perceived as pristine environments. However, atmospheric deposition of persistent organic pollutants (POPs) have been shown to expose these sensitive ecosystems to chemical pollution. Little is known on how this pollution impacts aquatic ecosystems at high altitudes. We combined passive sampling with liquid and gas chromatography high resolution mass spectrometry (LC- and GC-HRMS) to screen the water of eight lakes in three different regions of the French Pyrenees. In total, we screened for 479 organic chemicals including POPs, polycyclic aromatic hydrocarbons (PAHs), legacy and current-use pesticides, biocides, and musk fragrances. We detected a complex cocktail of 151 individual chemicals and used their toxic unit summation (ΣTU) to assess toxicity for crustaceans and algae. While risks for algae never reached chronic risks, this was always the case for crustaceans. Acute toxic risk thresholds for crustaceans were even exceeded in several of our sites. At sites with acute toxic risk levels (> 0.1 ΣTU) crustaceans were completely absent or showed a low abundance. We conclude that crustaceans were at least partly impacted by the high toxic risks driven by the insecticides diazinon and permethrin. These drugs are widely used to protect livestock from blue tongue disease transmitted by sucking insects, suggesting free roaming livestock as local source. Our results provide important evidence on toxic chemical pollution in relatively remote mountain areas, with important consequences for aquatic mountain ecosystems.

Pesticides are the dominant stressors for vulnerable insects in lowland streams.

Despite elaborate regulation of agricultural pesticides, their occurrence in non-target areas has been linked to adverse ecological effects on insects in several field investigations. Their quantitative role in contributing to the biodiversity crisis is, however, still not known. In a large-scale study across 101 sites of small lowland streams in Central Europe, Germany we revealed that 83% of agricultural streams did not meet the pesticide-related ecological targets. For the first time we identified that agricultural nonpoint-source pesticide pollution was the major driver in reducing vulnerable insect populations in aquatic invertebrate communities, exceeding the relevance of other anthropogenic stressors such as poor hydro-morphological structure and nutrients. We identified that the current authorisation of pesticides, which aims to prevent unacceptable adverse effects, underestimates the actual ecological risk as (i) measured pesticide concentrations exceeded current regulatory acceptable concentrations in 81% of the agricultural streams investigated, (ii) for several pesticides the inertia of the authorisation process impedes the incorporation of new scientific knowledge and (iii) existing thresholds of invertebrate toxicity drivers are not protective by a factor of 5.3 to 40. To provide adequate environmental quality objectives, the authorisation process needs to include monitoring-derived information on pesticide effects at the ecosystem level. Here, we derive such thresholds that ensure a protection of the invertebrate stream community.

Calibration and field application of the Atlantic HLB Disk containing Chemcatcher® passive sampler - Quantitative monitoring of herbicides, other pesticides, and transformation products in German streams.

The Chemcatcher® (CC) passive sampler containing an Atlantic HLB-L Disk (AD) was calibrated in a laboratory-based flow-through tank over 21 days under stirring for 38 polar organic pesticides with log Kow ranging from -1.7 to 3.8. The resultant sampling rates Rs range from 0.025 to 0.068 L/d. In 2018, field trials were conducted in the German rivers Mulde and Havel, as well as in 7 agricultural streams in Lower Saxony and Saxony-Anhalt. For 36 detected pesticides, the overall low concentrations were 0.2 to 49.4 ng/L. The determined pesticide profiles reflect agricultural use and were dominated by triazine herbicides including transformation products, by neonicotinoid insecticides, and by the herbicide mecoprop. Additional single hot spots were provided by the herbicides metamitron, isoproturon, and MCPA (showing the overall largest value of 49.4 ng/L). Notably, the detected waterborne pesticides include banned herbicides and associated transformation products in concentration ratios suggesting also recent input. This concerns in particular atrazine and its transformation products 2-OH-atrazine, deethylatrazine and deisopropylatrazine. An extended target screening of AD-CC extracts from the river Havel revealed the additional presence of other organic micropollutants including biocides, surfactants and industrial chemicals, and demonstrated the AD-CC applicability up to log Kow of 4.5.

Diffusion coefficients of polar organic compounds in agarose hydrogel and water and their use for estimating uptake in passive samplers.

Diffusion coefficient (D) is an important parameter for prediction of micropollutant uptake kinetics in passive samplers. Passive samplers are nowadays commonly used for monitoring trace organic pollutants in different environmental matrices. Samplers utilising a hydrogel layer to control compound diffusion are gaining popularity. In this work we investigated diffusion of several perfluoroalkyl substances, currently used pesticides, pharmaceuticals and personal care products in 1.5% agarose hydrogel by measuring diffusion coefficients using two methods: a diffusion cell and a sheet stacking technique. Further, diffusion coefficients in water were measured using Taylor dispersion method. The sheet stacking method was used to measure D at 5, 12, 24, and 33 °C in order to investigate temperature effect on diffusion. Median D values ranged from 2.0 to 8.6 × 10-6 cm2 s-1 and from 2.1 to 8.5 × 10-6 cm2 s-1 for the diffusion cell and sheet stack methods respectively. For most compounds, the variability between replicates was higher than the difference between values obtained by the two methods. Rising temperature from 10 to 20 °C increases the diffusion rate by the factor of 1.41 ± 0.10 in average. In water, average D values ranged from 3.03 to 10.0 × 10-6 cm2 s-1 and were comparable to values in hydrogel, but some compounds including perfluoroalkyl substances with a long aliphatic chain could not be evaluated properly due to sorptive interactions with capillary walls in the Taylor dispersion method. Sampling rates estimated using the measured D values were systematically higher than values estimated from laboratory sampler calibration in our previously published study, by the factor of 2.2 ± 1.0 in average.

Polyethersulfone as suitable passive sampler for waterborne hydrophobic organic compounds - Laboratory calibration and field test in the Sosiani river, Kenya.

We report the application of polyethersulfone (PES) membrane as a cost-saving and less labour-intensive single-phase passive sampler for waterborne hydrophobic organic compounds (HOCs) like organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs). The uptake kinetics of 31 HOCs from water to porous polyethersulfone (PES) membranes and their partitioning behaviour were investigated in laboratory studies. Sampling rates (Rs) of HOCs with PES were determined in a range from 1.15 to 12.9 L/d. The uptake of test chemicals and the elimination of analogous (pre-loaded) performance reference compounds (PRCs) showed anisotropy, both under laboratory and field conditions, implying that PRCs are not suitable for determining in situ sampling rates with PES. The PES-water partition coefficients (Kpw) are, on average, ten times higher than the related Kow. A Linear Solvation Energy Relationship for modelling the measured log Kpw with PES under inclusion of all available published data yields a poor fit in comparison to what is usually obtained with homogeneous polymers like polydimethylsiloxane or low-density polyethylene. At least a strong linear relationship was found between log Rs and log Kpw for the narrow log Kow range of HOCs investigated in this work which can be used for interpolation to other HOCs in this range. The PES membranes were also tested in a field trial in a tropical river against the well-established silicone rubber (SR) sheets. With laboratory-based Rs for PES generated under field-relevant temperature and water flow velocity it was possible to obtain time-weighted average concentrations in the lower ng/L range which are comparable (within a factor of two) with those derived from accumulated amounts in SR sheets (using in situ sampling rates).

Evaluation of polar organic chemical integrative and hollow fibre samplers for the determination of a wide variety of organic polar compounds in seawater.

The calibration of two passive samplers for the determination of 20 emerging organic compounds in seawater is described in this work: i) a new version of polar organic chemical integrative sampler (POCIS) containing 100 mg of mixed-mode anion exchanger (Strata X-AW) and 100 mg of polymeric HLB (Plexa) sorbent materials and using a highly porous Nylon membrane (30-µm pore size) and ii) polyethersulfone (PES) hollow fibre. Among the studied contaminants, herbicides, hormones, life style products (stimulants and artificial sweeteners), industrial chemicals (corrosion inhibitor and fluorinated compounds), personal care products and several pharmaceuticals were included. In the case of POCIS, both the sorbents and the Nylon membranes were extracted and analysed independently. The calibration set up consisted on a continuous-flow tank that was fed with a continuous flow of seawater (2 L/h) and a stock mixture of contaminants (20 mL/h), assuring a nominal concentration of ~ 600 ng/L (each analyte) in the tank. The uptake was linear in POCIS sorbent and Nylon membranes but exponential for PES hollow fibres. Furthermore, the highest sampling rates (Rs) values were obtained in POCIS sorbent (between 2.7 for acetaminophen and 491 mL/day for perfluoro-n-octanoic acid, PFOA) followed by Nylon membranes (between 3.6 for OBT and 50 mL/day for telmisartan) and the lowest were those from PES fibres (between 1.7 for bezafibrate and 157 mL/day for butylparaben). Additionally, five deuterated compounds ([2H5]-atrazine, [2H3]-amitriptyline, [2H7]-irbesartan, [2H3]-ketoprofen and [2H9]-progesterone) were studied as candidates for performance reference compounds (PRCs) in both POCIS and PES, and though [2H5]-atrazine, [2H9]-progesterone and [2H3]-amitriptyline showed acceptable results in the case of POCIS, only [2H5]-atrazine provided a good validation. In the case of PES fibres, the PRC corrections did not provide acceptable results due to a low dissipation of the PRCs. Finally, POCIS were deployed in two sites of the low part of the estuary of Bilbao (northern Spain) from where water samples were also taken and analysed. As a result, in addition to the overall good agreement between the passive and active samplings, passive samplers allowed the determination of several compounds that were below the detection limits in the active sampling.

Passive sampling for spatial and temporal monitoring of organic pollutants in surface water of a rural-urban river in Kenya.

Passive sampling is an emerging monitoring strategy for surface waters and can be applied in a range of environments including remote locations. Silicone rubber (SR) as a robust single-phase passive sampler was applied to characterize the spatial and temporal variability of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs) and three phthalates, namely, dibutyl phthalate (DBP), benzyl butyl phthalate (BBP) and bis(2-ethylhexyl)phthalate (DEHP) in a tropical river traversing rural and urban catchments. OCPs and PCBs were not detected. Up to 31.8ng/L of freely dissolved concentrations of PAHs were quantified and were dominated by the lower molecular weight members. Mean concentrations of DBP, BBP and DEHP were 72.6ng/L, 3.9ng/L and 7.1ng/L respectively. However, in sampling for phthalates using SR, quality control and assurance remains the key challenge and must always be ensured. Spatial variability in concentrations was evident and could be related to land use. Temporal variability was not significant.

Pesticides from wastewater treatment plant effluents affect invertebrate communities.

We quantified pesticide contamination and its ecological impact up- and downstream of seven wastewater treatment plants (WWTPs) in rural and suburban areas of central Germany. During two sampling campaigns, time-weighted average pesticide concentrations (cTWA) were obtained using Chemcatcher® passive samplers; pesticide peak concentrations were quantified with event-driven samplers. At downstream sites, receiving waters were additionally grab sampled for five selected pharmaceuticals. Ecological effects on macroinvertebrate structure and ecosystem function were assessed using the biological indicator system SPEARpesticides (SPEcies At Risk) and leaf litter breakdown rates, respectively. WWTP effluents substantially increased insecticide and fungicide concentrations in receiving waters; in many cases, treated wastewater was the exclusive source for the neonicotinoid insecticides acetamiprid and imidacloprid in the investigated streams. During the ten weeks of the investigation, five out of the seven WWTPs increased in-stream pesticide toxicity by a factor of three. As a consequence, at downstream sites, SPEAR values and leaf litter degradation rates were reduced by 40% and 53%, respectively. The reduced leaf litter breakdown was related to changes in the macroinvertebrate communities described by SPEARpesticides and not to altered microbial activity. Neonicotinoids showed the highest ecological relevance for the composition of invertebrate communities, occasionally exceeding the Regulatory Acceptable Concentrations (RACs). In general, considerable ecological effects of insecticides were observed above and below regulatory thresholds. Fungicides, herbicides and pharmaceuticals contributed only marginally to acute toxicity. We conclude that pesticide retention of WWTPs needs to be improved.

Applicability of polydimethylsiloxane (PDMS) and polyethersulfone (PES) as passive samplers of more hydrophobic organic compounds in intertidal estuarine environments.

The uptake calibration of three passive samplers, stir-bars, MESCO/stir-bars and polyethersulfone tubes (PESt), was assessed in seawater at different salinities for 17 organic compounds including organochlorine compounds, pesticides, phthalates, musk fragrances and triclosan. The calibration procedure was accomplished by exposing the samplers to a continuous flow of fortified seawater for up to 14days under laboratory conditions. Prior to the exposure, stir-bars and MESCO/stir-bars were loaded with a known amount of deuterated PAH mixture as performance reference compounds (PRC). For most of the studied compounds, the sampling rates (Rs, mL·day-1) were determined for each sampler at two salinities (15 and 30‰) and two nominal concentrations (25 and 50ng·L-1). Among the tested devices, though PES can be an outstanding cheap alternative to other passive samplers, naked or free stir-bars provided the best results in terms of uptake rates (i.e., the Rs values ranged from 30 to 350mL·day-1). Regarding the variation of the salinity, the Rs values obtained with naked stir-bars were statistically comparable in the full range of salinities (0-30‰) but the values obtained with MESCO/stir-bars and PESt were salinity dependent. Consequently, only stir-bars assured the required robustness to be used as passive samplers in intertidal estuarine environments. Finally, the stir-bars were applied to estimate the time-weighted average concentration of some of those contaminants in the feeding seawater of the experimental aquaria at the Plentzia Marine Station (Basque Country) and low levels of musks fragrances (0.1-0.2ng·L-1) were estimated.

Perfluoroalkyl acids in aqueous samples from Germany and Kenya.

Continuous monitoring of chemicals in the environment is important to control their fate and to protect human health, flora, and fauna. Perfluoroalkyl acids (PFAAs) have been detected frequently in different environmental compartments during the last 15 years and have drawn much attention because of their environmental persistence, omnipresence, and bioaccumulation potential. Water is an important source of their transport. In the present study, distributions of PFAAs in river water, wastewater treatment plant (WWTP) effluent, and tap water from eastern part of Germany and western part of Kenya were investigated. Eleven perfluorocarboxylic acids (PFCAs) and five perfluorosulfonic acids (PFSAs) were analyzed using liquid chromatography/tandem mass spectrometry. Sum of mean concentrations of eight PFAAs detected in drinking tap water from Leipzig was 11.5 ng L-1, dominated by perfluorooctanoic acid (PFOA, 6.2 ng L-1). Sums of mean riverine concentrations of PFAAs detected in Pleiße/White Elster, Saale, and Elbe (Germany) were 24.8, 54.3, and 26.8 ng L-1, respectively. Annual flux of PFAAs from River Saale was estimated to be 164 ± 23 kg a-1. The effluent of WWTP in Halle was found to contain four times higher levels of PFAAs than river water and was dominated by perfluorobutane sulfonate (PFBS) with 32 times higher concentration than the riverine level. It advocates that WWTPs are the point source of contaminating water bodies with PFAAs, and short-chain PFAAs are substituting long-chain homologues. Sums of mean riverine concentrations of PFAAs in Sosiani (Kenya) in samples from sparsely populated and densely populated areas were 58.8 and 109.4 ng L-1, respectively, indicating that population directly affected the emissions of PFAAs to surface waters. The discussion includes thorough review and comparison of recently published literature reporting occurrence of PFAAs in aqueous matrices. Graphical abstract Perfluoroalkyl acids in aqueous matrices.

Adsorption of perfluorocarboxylic acids at the silica surface.

Water molecules may force the hydrophobic perfluoroalkyl chain of perfluorocarboxylic acids (PFCAs) to aggregate at hydrophobic siloxane patches ([triple bond, length as m-dash]Si-O-Si[triple bond, length as m-dash]) of the silica surface despite electrostatic repulsion between surface silanol ([triple bond, length as m-dash]SiO-) and the carboxylate (-COO-) headgroup of PFCA. Acidic pH and background cations promote the adsorption further by reducing the anion-anion Coulomb repulsion.

Gas chromatographic determination of perfluorocarboxylic acids in aqueous samples - A tutorial review.

Determination of perfluorocarboxylic acids (PFCAs) by gas chromatography (GC) has been undertaken since 1980. However, only small number of studies can be found in the literature due to the major drawbacks associated with the GC determination of PFCAs such as high detection limits, a small range of analytes, long analysis time, and laborious derivatization prior to chromatographic separation. Liquid chromatography-tandem mass spectrometry (LC-MS2) can overcome these limitations of GC, and therefore has become the method of choice for the determination of PFCAs since 2001. Nevertheless, GC as a low-cost and commonly available analytical technique should not be ignored because of its inherent advantage over LC to identify PFCA isomers in environmental and biological matrices owing to its high-resolution power. In addition, GC provides an opportunity to crosscheck LC-MS2 results that are often suspicious due to background contamination. This tutorial provides an overview of GC methods that have been used for the determination of PFCAs after derivatization. Moreover, performance characteristics of GC-MS are compared with that of LC-MS2. PFCAs in aqueous samples were determined by both analytical techniques, and two sets of measurements were compared using the Bland-Altman plot. For both methods, reasons for false-positive and false-negative results (overestimation and underestimation of the PFCA concentration, respectively) are discussed, and accordingly some advice is offered on how to avoid erroneous results. Finally, major applications of GC and its future perspectives for the determination of PFCAs are discussed.

Uptake calibration of polymer-based passive samplers for monitoring priority and emerging organic non-polar pollutants in WWTP effluents.

The uptake calibration of more than 12 non-polar organic contaminants by 3 polymeric materials is shown: bare polydimetilsiloxane (PDMS, stir-bars), polyethersulfone tubes and membranes (PES) and polyoxymethylene membranes (POM), both in their free form and membrane-enclosed sorptive coating (MESCO). The calibration process was carried out exposing the samplers to a continuous flow of contaminated water at 100 ng mL(-1) for up to 28 days, and, consequently, the sampling rates (Rs, mL day(-1)) of several organic microcontaminants were provided for the first time. In situ Rs values were also determined disposing the samplers in the effluent of a wastewater treatment plant. Finally, these passive samplers were applied to monitor the effluents of two wastewater treatment plants. This application lead to the confirmation of the presence of galaxolide, tonalide and 4-tert-octylphenol at high ng mL(-1) levels, as well as the identification of compounds like some phthalates and alkylphenols at levels below the detection limits for active sampling methods.

Distribution of polychlorinated biphenyls, phthalic acid esters, polycyclic aromatic hydrocarbons and organochlorine substances in the Moscow River, Russia.

The purpose of this study was to investigate the levels of polychlorinated biphenyl (PCB), phthalic acid esters (PAE), polycyclic aromatic hydrocarbons (PAH) and organochlorine substances (OCP) in the Moscow River water. Some studies have reported the occurrence of these substances in the soil of the Moscow region; however, no study has yet established an overview for these compounds in the Moscow River water. In this study the Moscow River water contamination with PAEs, PAHs and OCPs was determined. Obtained results were associated with the resident area located on the river bank, and the possible contamination sources were considered. The obtained data were compared with the data on the contamination of the different world-wide rivers. This research indicates the further study necessity of the Moscow region to cover more contaminated sites and environmental compartments.