Models such as the Biotic Ligand Model (BLM) predict how natural organic matter (NOM) and competing ions (e.g., Ca(2+), H(+) and Na(+)) affect metal bioavailability and toxicity in aquatic organisms. However, such models focus upon individual metals, not metal mixtures. This study determined whether Pb and Cd interact at the gill of rainbow trout (Oncorhynchus mykiss) when trout were exposed to...

The lipophilic nucleoside, G 1, extracts Pb(2+) picrate from water into organic solvents to give structures based on the hydrogen-bonded G-quartet. Crystal structures indicate important differences between (G 1)(8)-Pb(2+) and (G 1)(8)-K(+). The divalent Pb(2+) templates a smaller G(8) cage than does K(+), as judged by the M-O6 bond length, O6-O6 diagonal distance, and inter-tetramer separation....

1:1 and 1:2 lead(II) complexes with 2,9-dimethyl-1,10-phenanthroline (Dmphen), {[Pb(Dmphen)(NO3)n] and [Pb(Dmphen)2(ClO4)2]} have been synthesized and characterized by CHN elemental analysis, IR, 1H NMR, 13C NMR and 207Pb NMR spectroscopy. The structure of these complexes was confirmed by X-ray crystallography. The single crystal X-ray data of [Pb(Dmphen)(NO3)n] show the complex to be polymeric...

The effect of the dosing vehicle (e.g., dough) on the ability of an in vitro gastrointestinal (IVG) method to predict relative bioavailable Pb associated with soil ingestion was evaluated. Bioaccessible Pb determined by the IVG method was compared with relative bioavailable Pb measured from dosing trials using juvenile swine for 18 contaminated soils ranging from 1270 to 14200 mg Pb kg(-1). Bio...

The role of apurinic/apyrimidinic endonuclease1/redox factor-1 (Ref-1) on the lead (Pb)-induced cellular response was investigated in the cultured endothelial cells. Pb caused progressive cellular death in endothelial cells, which occurred in a concentration- and time-dependent manner. However, Ref-1 overexpression with AdRef-1 significantly inhibited Pb-induced cell death in the endothelial ce...

Stream sediments from the mining and smelting district of Príbram, Czech Republic, were studied to determine the degree, sources and dispersal of metal contamination using a combination of bulk metal and mineralogical determinations, sequential extractions and Pb isotopic analyses. The highest metal concentrations were found 3-4 km downstream from the main polymetallic mining site (9800 mg Pb k...

Lead (Pb) released from anthropogenic sources and stored in environmental repositories can be a potential source for secondary pollution. Here we develop a novel approach for tracking Pb from atmospheric deposition and other sources in the environment using fallout (210)Pb as a tracer, and apply the method to samples collected from Richmond Park, London, the UK. The mean ratio of (210)Pb to tot...

The effect of aging on the bioaccessibility of As and Pb in three soils spiked with As (40 or 400 mg kg(-1)), Pb (150 or 1500 mg kg(-1)) or As + Pb (40 mg kg(-1) As and 150 mg kg(-1) Pb) were investigated using the physiologically based extraction test (PBET). Prolonged aging in soils resulted in a decrease in As/Pb bioaccessibility, especially within the first month. After 76 weeks, As/Pb bioa...

We coupled the diffusive gradients in thin-films (DGT) technique with two sequential extraction methods to investigate the influence of aging on As and Pb fractionation and availability in three soils spiked with As (40 or 400mgkg(-1)), Pb (150 or 1500mgkg(-1)) or As+Pb (40mgkg(-1) As and 150mgkg(-1) Pb). During aging, As moved from the more available (non-specifically and specifically sorbed) ...