Passive samplers based on diffusive gradients in thin hydrogel films (DGT) were recently modified for sampling of polar organic compounds in water. However, since the sampling rates of the commonly used DGT design with the surface area of 3.1 cm2 are low, we propose to increase them by applying a two-sided design with a larger sampling surface area of 22.7 cm2. The sampler design consists of two sorptive hydrogel disks compressed between two diffusive hydrogel disk layers strengthened by nylon netting and held together by two stainless steel rings. Sorbent/water distribution coefficients (KSW) were determined, and the sampler was calibrated for monitoring 11 perfluoroalkyl substances and 12 pharmaceuticals and personal care products in water at laboratory conditions using a closed system with artificial flow generated by submersible pumps. A field performance test was conducted at five locations in the Morava River basin in Czech Republic. The median value of laboratory-derived sampling rates was 43 mL day-1 with extreme values of 2 mL day-1 and 90 mL day-1 for perfluorotridecanoic and perfluoroheptanoic acids, respectively. The log KSW values of tested compounds ranged from 3.18 to 5.47 L kg-1, and the estimated halftime to attain sampler-water equilibrium ranged from 2 days to more than 28 days, which is the maximum recommended exposure period, considering potential issues with the stability of hydrogel. The sampler can be used for assessment of spatial trends as well as estimation of aqueous concentration of investigated polar compounds.

• Keywords
• Diffusive gradients in thin films (DGT), Hydrogel, Passive sampling, Polar organic compounds, Water monitoring,
• MeSH
• Water Pollutants, Chemical analysis   MeSH
• Diffusion MeSH
• Fluorocarbons chemistry   MeSH
• Hydrogels chemistry   MeSH
• Heptanoic Acids chemistry   MeSH
• Organic Chemicals chemistry   MeSH
• Rivers chemistry   MeSH
• Sepharose chemistry   MeSH
• Water MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Czech Republic MeSH
• Names of Substances
• Water Pollutants, Chemical MeSH
• Fluorocarbons MeSH
• Hydrogels MeSH
• Heptanoic Acids MeSH
• Organic Chemicals MeSH
• perfluoro-n-heptanoic acid MeSH Browser
• Sepharose MeSH
• Water MeSH

Concentrations and isomer compositions of hexabromocyclododecane (HBCD) were measured in six matrices in the Czech Republic (HBCD technical mixture; consumer products; indoor and outdoor air at industrial, urban and background locations; soils; and sediments) to provide insight into changes in concentrations and isomer profiles between environmental sources and environmental sinks. A distinct gradient of air concentrations was observed, from 1600 ng/m3 in the industrial area to < 10 pg/m3 in urban and background air. Isomer profiles also showed a distinct gradient in air, from 95% γ-HBCD in industrial air to 40% γ-HBCD in background air, suggesting the influence of differential atmospheric transport and phototransformation of γ- to α-HBCD. Concentrations and isomer compositions in consumer products were highly variable and indicated differences between products with intentional addition of HBCD as a flame retardant versus those with HBCD as an impurity, e.g., from recycled plastic. Understanding the isomer-specific environmental distributions and processes remains important for risk assessment and toxicology, considering the continued use of HBCD and the isomer-specific differences in uptake, metabolism, and toxicity, and further, demonstrates the utility of isomer profiles to better understand environmental processes of HBCDs.

• Keywords
• Atmospheric transport, Consumer products, Flame retardants, HBCD, Isomer profiles, Sources,
• MeSH
• Hydrocarbons, Brominated analysis   chemistry   MeSH
• Isomerism MeSH
• Environmental Pollutants analysis   chemistry   MeSH
• Environmental Monitoring methods   MeSH
• Soil chemistry   MeSH
• Flame Retardants analysis   MeSH
• Consumer Product Safety MeSH
• Air analysis   MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Czech Republic MeSH
• Names of Substances
• Hydrocarbons, Brominated MeSH
• hexabromocyclododecane MeSH Browser
• Environmental Pollutants MeSH
• Soil MeSH
• Flame Retardants MeSH

The main topic of this study is a human health risk assessment of a defined exposure scenario in the floodplain soils of the headwater areas of the central European watershed, with the aim of exploring both multivariate and regional data structures. Flood-prone areas are recognized worldwide to be susceptible to contamination and its redistribution. Contributions of various classes of toxic compounds (organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs)) to human health risks were assessed in a screening risk assessment. However, due to the relative nature of our data and a high PAH dominancy over the data ensemble, reliance solely on the standard statistical processing of raw data might lead to incomplete insight into the structure of the multivariate data. Explanatory analysis of the data structure using the compositional approach was found to be beneficial to elucidating human health risk profiles and provided robust evidence that a contrast between agricultural and airborne industrial pollution controlled the whole human toxicological variation of persistent organic pollutants (POPs) in floodplain soils. These results were effectively quantified with the subcomposition of benzo(a)pyrene, DDT, and alpha-hexachlorocyclohexane (aHCH), allowing for an interpretation of structural differences in regional pollution patterns, which conferred different extents and compositions of human health risks in floodplain soils.

• Keywords
• compositional data, floodplain, human health risk, soil pollution,
• MeSH
• Algorithms MeSH
• Hydrocarbons, Chlorinated analysis   MeSH
• Hexachlorocyclohexane analysis   MeSH
• Soil Pollutants analysis   MeSH
• Environmental Pollutants analysis   MeSH
• Humans MeSH
• Environmental Monitoring * MeSH
• Pesticides analysis   MeSH
• Polychlorinated Biphenyls analysis   MeSH
• Polycyclic Aromatic Hydrocarbons analysis   MeSH
• Soil chemistry   MeSH
• Floods * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Europe MeSH
• Names of Substances
• alpha-hexachlorocyclohexane MeSH Browser
• Hydrocarbons, Chlorinated MeSH
• Hexachlorocyclohexane MeSH
• Soil Pollutants MeSH
• Environmental Pollutants MeSH
• Pesticides MeSH
• Polychlorinated Biphenyls MeSH
• Polycyclic Aromatic Hydrocarbons MeSH
• Soil MeSH

Changes in pollutant loads in relatively dynamic river sediments, which contain very complex mixtures of compounds, can play a crucial role in the fate and effects of pollutants in fluvial ecosystems. The contamination of sediments by bioactive substances can be sensitively assessed by in vitro bioassays. This is the first study that characterizes detailed short- and long-term changes in concentrations of contaminants with several modes of action in river sediments. One-year long monthly study described seasonal and spatial variability of contamination of sediments in a representative industrialized area by dioxin-like and endocrine disruptive chemicals. There were significant seasonal changes in both antiandrogenic and androgenic as well as dioxin-like potential of river sediments, while there were no general seasonal trends in estrogenicity. Aryl hydrocarbon receptor-dependent potency (dioxin-like potency) expressed as biological TCDD-equivalents (BIOTEQ) was in the range of 0.5-17.7 ng/g, dry mass (dm). The greatest BIOTEQ levels in sediments were observed during winter, particularly at locations downstream of the industrial area. Estrogenicity expressed as estradiol equivalents (EEQ) was in the range of 0.02-3.8 ng/g, dm. Antiandrogenicity was detected in all samples, while androgenic potency in the range of 0.7-16.8 ng/g, dm dihydrotestosterone equivalents (DHT-EQ) was found in only 30 % of samples, most often during autumn, when antiandrogenicity was the least. PAHs were predominant contaminants among analyzed pollutants, responsible, on average, for 13-21 % of BIOTEQ. Longer-term changes in concentrations of BIOTEQ corresponded to seasonal fluctuations, whereas for EEQ, the inter-annual changes at some locations were greater than seasonal variability during 1 year. The inter- as well as intra-annual variability in concentrations of both BIOTEQ and EEQ at individual sites was greater in spring than in autumn which was related to hydrological conditions in the river. This study stresses the importance of river hydrology and its seasonal variations in the design of effective sampling campaigns, as well as in the interpretation of any monitoring results.

• MeSH
• Biological Assay MeSH
• Water Pollutants, Chemical analysis   MeSH
• Water Pollution, Chemical statistics & numerical data   MeSH
• Dioxins analysis   MeSH
• Endocrine Disruptors analysis   MeSH
• Geologic Sediments chemistry   MeSH
• Environmental Monitoring * MeSH
• Polychlorinated Dibenzodioxins analysis   MeSH
• Polycyclic Aromatic Hydrocarbons analysis   MeSH
• Receptors, Aryl Hydrocarbon MeSH
• Rivers chemistry   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Water Pollutants, Chemical MeSH
• Dioxins MeSH
• Endocrine Disruptors MeSH
• Polychlorinated Dibenzodioxins MeSH
• Polycyclic Aromatic Hydrocarbons MeSH
• Receptors, Aryl Hydrocarbon MeSH