Sci Total Environ
September 2024
Elucidating the factors affecting the transfer of naturally occurring radionuclides (NOR) between environmental compartments is a key part of the assessment of ecosystem's exposure to naturally occurring radionuclide materials (NORM). For that, the sorption and desorption solid-liquid distribution coefficients (K) of radium (Ra) were quantified in a collection of 31 soil samples with contrasting edaphic properties under controlled conditions in laboratory batch experiments. Ra sorption was demonstrated to be moderate to high, with K (Ra) values ranging from 10 to 10 L kg.
View Article and Find Full Text PDFThe presence of fluoroquinolone (FQ) antibiotics in soils may cause a threat to human health due to overexposure and the generation of antibiotic resistance genes. Understanding their sorption behavior in soils is important to predict subsequent FQ (bio) availability. Here, FQ sorption in pure soil organic (i.
View Article and Find Full Text PDFFluoroquinolone antibiotics (FQs) are of concern due to their disrupting effects on environmental bacterial communities. Evaluating FQ sorption by soil components is important to understand their interaction with soils and to address their environmental (bio)availability. However, data in soil organic components, especially humic acids, are scarce.
View Article and Find Full Text PDFSci Total Environ
February 2023
The evaluation of the sorption affinity of fluoroquinolone antibiotics (FQs) in soils, by means of the derivation of solid-liquid distribution coefficients (K), is a valuable information for assessing their environmental mobility. Aiming to develop K (FQ) prediction tools in soils, in the first stage of this study we constructed a K (FQ) sorption dataset using current literature data. Furthermore, additional sorption and desorption data for norfloxacin were obtained in seven different soils of contrasting properties.
View Article and Find Full Text PDFA prototype tool has been developed for deriving sediment distribution coefficients,, in the marine environment by harvesting simultaneous measurements of activity concentrations of radionuclides in seawater and sediments based on the International Atomic Energy Agency's Marine Radioactivity Information System (MARIS). As a case study, thevariability in the Baltic Sea was investigated as this region has been extensively monitored by HELCOM since 1984 resulting in a comprehensive dataset with good spatial and temporal coverage and required ancillary parameters. The prototype tool was used to derive a dataset ofapparentvalues derived from measurements of seawater and sediment in quasi-equilibrium conditions from the Baltic Sea over a period of approximately 35 years.
View Article and Find Full Text PDFThe use of carbon-rich sorbents to remove and/or immobilize perfluoroalkyl substances (PFAS) in contaminated environmental scenarios is attracting increasing interest. The identification of key sorbent properties responsible for PFAS sorption and the development of models that can predict the distribution coefficients (K) for PFAS sorption in these materials are crucial in the screening of candidate materials for environmental remediation. In this study, sorption kinetics, sorption isotherms, and the effects of pH, calcium concentration and dissolved organic carbon (DOC) content on PFAS sorption were evaluated in four representative carbon-rich materials: two biochars with contrasting properties, a compost, and charcoal fines rejected by the metallurgical industry.
View Article and Find Full Text PDFSamarium (Sm) sorption from aqueous solutions was evaluated in biochars (derived from castor meal (CM), eucalyptus forest residues (CE), sugarcane bagasse (SB) and green pericarp of coconut (PC)) and in other carbon-rich materials (coal fines (CF); two commercial activated charcoals (GAC, NGAC)) by applying batch and continuous-flow sorption experiments. Batch experiments revealed great K values, in the range of 10-10 L kg, and high Sm sorption percentages (>97%, except for SB) in the range of environmental representative concentrations, using as-received materials, with no further treatments. Maximum sorption capacities were derived from sorption isotherms using the Langmuir model (from 1.
View Article and Find Full Text PDFA simple parametric model was developed to predict the sorption of perfluoroalkyl substances (PFASs) in soils. Initially, sorption and desorption solid-liquid distribution coefficients (K and K respectively) of eight PFASs (five perfluoroalkyl carboxylates, PFCAs, and three perfluoroalkane sulfonates, PFSAs) in seven soils with organic carbon (OC) content ranging from 1.6 to 41% were quantified using batch experiments.
View Article and Find Full Text PDFThe ALLIANCE Strategic Research Agenda (SRA) for radioecology is a living document that defines a long-term vision (20 years) of the needs for, and implementation of, research in radioecology in Europe. The initial SRA, published in 2012, included consultation with a wide range of stakeholders (Hinton et al., 2013).
View Article and Find Full Text PDFThe solid-liquid distribution coefficient (K) is a key input parameter in radioecological models. However, its large variability hampers its usefulness in modelling transport processes as well as its accuracy in representing soil-radionuclide interactions. For the specific case of radiocaesium, the analyses of a Cs K soil dataset (769 entries) showed that values varied over a five order of magnitude range, and the resulting Cs K best estimate (calculated as a geometric mean = 2.
View Article and Find Full Text PDFThe solid-liquid distribution coefficient (K) is a key input parameter in radioecological risk models. However, its large variability hampers its usefulness in modelling transport processes as well as its accuracy in representing soil-radionuclide interactions. To assist in the selection of K values and their cumulative distribution functions for study areas without site specific information, a critically reviewed dataset was developed, containing more than 5000 soil K entries for 83 elements and an additional 2000 entries of K data for 75 elements gathered from a selection of other geological materials.
View Article and Find Full Text PDFA general approach is presented to derive probabilistic radionuclide distribution coefficients (K) in soils from a K dataset. The main aim was to derive informed estimates with a low inherent uncertainty by restricting the K value data to subsets based on key soil factors and the experimental approach used to calculate the K value (e.g.
View Article and Find Full Text PDFThis work investigates the sorption of heavy metals by low-cost, byproducts such as charcoal fines (CF), waste green sand, and rice husk ash, in order to examine the feasibility of their use as alternative filter materials for metal-contaminated waters. The sorption of Cd, Cu, Pb, and Zn was investigated in batch experiments and sorption isotherms were constructed. The three byproducts showed high metal removal efficiencies (>95%, regardless of the metal concentration tested).
View Article and Find Full Text PDFThe sorption and desorption behaviour of samarium (Sm), an emerging contaminant, was examined in soil samples at varying Sm concentrations. The obtained sorption and desorption parameters revealed that soil possessed a high Sm retention capacity (sorption was higher than 99% and desorption lower than 2%) at low Sm concentrations, whereas at high Sm concentrations, the sorption-desorption behaviour varied among the soil samples tested. The fractionation of the Sm sorbed in soils, obtained by sequential extractions, allowed to suggest the soil properties (pH and organic matter solubility) and phases (organic matter, carbonates and clay minerals) governing the Sm-soil interaction.
View Article and Find Full Text PDFThe 2014 Strategic Research Agenda (SRA) for Radioecology identified the key challenge in education and training (E&T) as being 'to maintain and develop a skilled workforce in Europe and world-wide, through university candidates and professionals trained within radioecology' since 'scientific research in radioecology and application of that knowledge … requires scientists and workers with adequate competence and appropriate skills.' Radioecology is a multidisciplinary science and E&T is needed by both students and professionals within research, industry and radiation protection. In order to address these needs, the EU COMET project has developed an E&T web platform and arranged a number of field courses, training courses, PhD and MSc courses, refresher courses and workshops, drawing on the COMET consortium to assemble relevant experts.
View Article and Find Full Text PDFMotivation: Computational prediction of protein-protein complex structure by docking can provide structural and mechanistic insights for protein interactions of biomedical interest. However, current methods struggle with difficult cases, such as those involving flexible proteins, low-affinity complexes or transient interactions. A major challenge is how to efficiently sample the structural and energetic landscape of the association at different resolution levels, given that each scoring function is often highly coupled to a specific type of search method.
View Article and Find Full Text PDFThe effect of the addition of industrial by-products (gypsum and calcite) on the leaching of As and metals (Cu, Zn, Ni, Pb and Cd) in a soil contaminated by pyritic minerals was monitored over a period of 6 months at a two-pit pilot plant. The contaminated soil was placed in one pit (non-remediated soil), whereas a mixture of the contaminated soil (80% w/w) with gypsum (10% w/w) and calcite (10% w/w) was placed in the other pit (remediated soil). Soil samples and leachates of the two pits were collected at different times.
View Article and Find Full Text PDFThe sorption behaviour of three perfluoroalkyl substances (PFASs) (perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutanesulfonic acid (PFBS)) was studied in sewage sludge samples. Sorption isotherms were obtained by varying initial concentrations of PFOS, PFOA and PFBS. The maximum values of the sorption solid-liquid distribution coefficients (Kd,max) varied by almost two orders of magnitude among the target PFASs: 140-281 mL g(-1) for PFOS, 30-54 mL g(-1) for PFOA and 9-18 mL g(-1) for PFBS.
View Article and Find Full Text PDFObjectives: To describe the clinical characteristics of fire smoke inhalation victims and carboxyhemoglobin values (Sp- CO) recorded with a portable pulse carbon monoxide (CO) oximeter at rescue sites in Catalonia. To assess the contribution of SpCO information to decision-making during emergency transfers.
Material And Methods: Retrospective observational study.
The sorption behaviour of three perfluoroalkyl substances (PFASs), perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutane sulfonic acid (PFBS), was studied in six soils with contrasting characteristics, especially in the organic carbon content. Sorption isotherms were obtained by equilibrating the soil samples with 0.01 mol L(-1) CaCl2 solutions spiked with increasing concentrations of the target PFAS.
View Article and Find Full Text PDFMeasles incidence declined until becomes a sporadic reporting and infrequent notification in the last decade. The reemergence of the disease reached 744 cases in 2012, a rate of 14.50×10(5) inhabitants.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
February 2014
Reusing sewage sludge as a soil fertiliser has become a common alternative to disposal. Although this practice has a few benefits, it may contribute to the medium- and long-term contamination of the trophic chain because sewage sludge may contain heavy metals and organic contaminants. As the leaching of contaminants may depend on the sludge pre-treatment, the leaching of heavy metals (Cu, Ni, Pb, Zn and Cr) and alkylphenolic compounds (APCs) (octylphenol (OP), nonylphenol (NP), nonylphenol-mono-ethoxylate (NP1EO)) was investigated in five fresh and 40 °C dried sewage sludge samples from north-eastern Spain.
View Article and Find Full Text PDFThe competitive effect of La and Lu (analogues of radionuclides appearing in radioactive waste) in the sorption in four smectites was examined. Sorption and desorption distribution coefficients (K(d); K(d,des)), and desorption rates (R(des)) were determined from batch tests in two media: deionized water and, to consider the influence of cement leachates, 0.02 mol L(-1) Ca.
View Article and Find Full Text PDFThe sorption reversibility of La and Lu (considered as actinide analogues) onto a set of smectites (bentonite FEBEX; hectorite, HEC; MX80; saponite, SAP; Otay montmorillonite, SCa-3; and Texas montmorillonite, STx-1) was studied to estimate actinide retention by smectites that are candidates for use as engineered barriers in deep geological repositories. The sorption distribution coefficients (K(d)) and the reversibility parameters (desorption distribution coefficients (K(d,des)), adjusted distribution coefficients (K(d,adj)), and desorption rates (R(des))) were determined from batch tests in two ionic media: deionized water and Ca 0.02 mol L(-1).
View Article and Find Full Text PDFThe objective of this study was to compile data, based on an extensive literature survey, for the soil solid-liquid distribution coefficient (K(d)) and soil-to-plant transfer factor (TF) for nickel. The K(d) best estimates were calculated for soils grouped according to texture and organic matter content (sand, loam, clay and organic) and soil cofactors affecting soil-nickel interaction, such as pH, organic matter, and clay content. Variability in K(d) was better explained by pH than by soil texture.
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