We report the solid-liquid partitioning of Cd, Cu, Ni, Pb, and Zn in 60 organic horizon samples of forest soils from the Hermine Watershed (St-Hippolyte, PQ, Canada). The mean Kd values are respectively 1132, 966, 802, 3337 and 561. Comparison of those Kd coefficients to published compilation values show that the Kd values are lower in acidic organic soil horizons relative to the overall mean Kd values compiled for mineral soils. But, once normalized to a mean pH of 4.4, the Kd values in organic soil horizons demonstrate the high sorption affinity of organic matter, which is either as good as or up to 30 times higher than mineral soil materials for sorbing trace metals. Regression analysis shows that, within our data set, pH and total metal contents are not consistent predictors of metal partitioning. Indeed, metal sorption by the solid phase must be studied in relation to complexation by dissolved organic ligands, and both processes may sometime counteract one another.
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Lipophilicity and blood partitioning are important determinants for predicting toxicokinetics using physiologically-based toxicokinetic (PBTK) modeling. In this study, the logarithm of the -octanol:water partition coefficient (log) and the blood-to-plasma concentration ratio ( ) were for the first time experimentally determined for the pyrrolizidine alkaloids (PAs) intermedine, lasiocarpine, monocrotaline, retrorsine and their -oxides (PANOs). Validated assays for log (miniaturized shake-flask method) and (LC-MS/MS-based depletion assay) determination were compared to an ensemble of models.
View Article and Find Full Text PDFNat Chem
January 2025
Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, State Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, Wuhan, China.
The properties and functions of metal-organic frameworks (MOFs) can be tailored by tuning their structure, including their shape, porosity and topology. However, the design and synthesis of complex structures in a predictable manner remains challenging. Here we report the preparation of a series of isomeric pillar-layered MOFs, and we show that their three-dimensional topology can be controlled by altering the layer stacking.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of California Riverside, Chemistry Department, Chemistry Department, 92521, Riverside, UNITED STATES OF AMERICA.
Although metal-organic frameworks are coordination-driven assemblies, the structural prediction and design using metal-ligand interactions can be unreliable due to other competing interactions. Leveraging non-coordination interactions to develop porous assemblies could enable new materials and applications. Here, we use a multi-module MOF system to explore important and pervasive impact of ligand-ligand interactions on metal-ligand as well as ligand-ligand co-assembly process.
View Article and Find Full Text PDFEnviron Pollut
January 2025
Xi'an Jinborui Ecological Tech. Co., Ltd., Xi'an, 710065, China.
As a crucial component of soil organic matter, humic acid (HA) persists in soil and exert a complex interaction with hydrophobic organic pollutants, yet its specific role still remains unclear. In this study, HA was obtained from weathered coal via alkaline dissolution and acidic precipitation for the adsorption of benzo[a]anthracene (BAA). Subsequently, an aging simulation was employed to assess its long-term performance.
View Article and Find Full Text PDFSci Total Environ
January 2025
Centro de Genómica, Ecología y Medio Ambiente (GEMA), Universidad Mayor, Campus Huechuraba, Santiago, Chile; Institute of Environment, Florida International University, University Park, Miami, FL 33199, USA; Data Observatory Foundation, Santiago, Chile. Electronic address:
Semi-volatile organic compounds (SVOCs) are widely distributed across the globe, including polar regions. This study investigates the distribution and bioconcentration of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in soils and Colobanthus quitensis, while also estimating potential emission sources. Results indicated high concentrations of PAHs in soils and plants from the Sub-Antarctic region, while OCPs and PCBs were more prevalent in the Antarctic region, with higher contaminant concentrations found in soils than in plant tissues.
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