A modeling approach to predict population-level impact of silver (Ag) to rainbow trout (Oncorhynchus mykiss).

Metal bioavailability plays a pivotal role in determining the toxicity of silver (Ag) to freshwater fish, such as rainbow trout (Oncorhynchus mykiss). The current study builds on an existing sodium balance model, a physiological extension of biotic ligand models (BLM). This model mechanistically describes the impact of Ag on Na ionoregulation in rainbow trout and predicts lethal effects under various Ag bioavailability conditions.

Comparative in vivo toxicokinetics of silver powder, nanosilver and soluble silver compounds after oral administration to rats.

Silver (Ag; massive, powder and nanoform) and Ag compounds are used in industrial, medical and consumer applications, with potential for human exposure. Uncertainties exist about their comparative mammalian toxicokinetic ('TK') profiles, including their relative oral route bioavailability, especially for Ag massive and powder forms. This knowledge gap impedes concluding on the grouping of Ag and Ag compounds for hazard assessment purposes.

European freshwater silver monitoring data do not suggest a potential European-wide risk.

European legislations frequently focus on substances that are of potential concern to human or environmental health, such as "priority substances" under the Water Framework Directive 2000/60/EC ("WFD") that are identified as substances posing a significant risk to or via the aquatic environment. The EU REACH regulation also requires the assessment of the environmental risks of chemicals put on the EU market. To properly assess the potential risk of a substance, high-quality representative monitoring data should be compared with a safe threshold concentration.

Setting a Protective Threshold Value for Silver Toward Freshwater Organisms.

Driven by Regulation (EC) No. 1272/2008 and the European Water Framework Directive 2000/60/EC, we have re-evaluated the available chronic freshwater ecotoxicity data for ionic silver (Ag) using strict data quality criteria. In addition, we generated new chronic ecotoxicity data for species potentially sensitive to Ag (the rotifer Brachionus calyciflorus, the cyanobacteria Anabaena flos-aquae, and the aquatic plant Lemna minor) using Ag nitrate as the test substance.

Effects of Silver Nitrate are a Conservative Estimate for the Effects of Silver Nanoparticles on Algae Growth and Daphnia magna Reproduction.

Silver (Ag) salts have been shown to be highly toxic to freshwater organisms. There is nevertheless still a high level of uncertainty as to the aquatic effects of Ag nanoparticles (AgNPs), and how these relate to the effects of soluble Ag salts. As part of the substance evaluation for Ag of the European Union Registration, Evaluation, Authorisation, and Restriction of Chemicals regulation, we have generated new data to justify read-across from soluble Ag salts to AgNPs.

Transformation-dissolution reactions partially explain adverse effects of metallic silver nanoparticles to soil nitrification in different soils.

Risk assessment of metallic nanoparticles (NPs) is critically affected by the concern that toxicity goes beyond that of the metallic ion. The present study addressed this concern for soils with silver nanoparticles (AgNPs) using the Ag-sensitive nitrification assay. Three agricultural soils (A, B, and C) were spiked with equivalent doses of either AgNP (diameter = 13 nm) or AgNO .

Experimental parameters affecting sensitivity and specificity of a yeast assay for estrogenic compounds: results of an interlaboratory validation exercise.

In vitro assays are considered as the first step in a tiered approach to compound screening for hormonal activity. Although many new assays have been developed in recent years, little attention has been paid towards assay validation. Our objective was to identify critical experimental parameters in a yeast estrogen screen (YES) that affect its sensitivity and specificity.

Flame retardants, surfactants and organotins in sediment and mysid shrimp of the Scheldt estuary (The Netherlands).

Sediment and mysids from the Scheldt estuary, one of the largest and most polluted estuaries in Western Europe, were analyzed for a number of contaminants that have been shown to possess endocrine-disrupting activity, i.e. organotins, polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), tetrabromobisphenol A (TBBPA), nonylphenol ethoxylates (NPE) and transformation products, nonylphenol (NP) and nonylphenol ether carboxylates (NPEC).

In vitro and in vivo estrogenicity and toxicity of o-, m-, and p-dichlorobenzene.

The estrogenicity of o-, m-, and p-dichlorobenzene (DCB) was evaluated with a yeast estrogen screen (YES) and zebrafish (Danio rerio) vitellogenin (VTG) assays. With the YES, p-DCB and m-DCB were found to be estrogenic in a concentration-responsive manner. The relative potency measured with the YES (relative to 17beta-estradiol) was 2.

Induction of vitellogenesis in 17alpha-ethinylestradiol-exposed rainbow trout (Oncorhynchus mykiss): a method comparison.

Juvenile rainbow trout, Oncorhynchus mykiss, were exposed to the synthetic estrogen 17alpha-ethinylestradiol (EE(2)) through injection (1, 10, 25 and 50 microg EE(2)/g fish/week) and via water exposure (1, 10 and 100 ng EE(2)/l). After seven (injection and water exposure) and 14 days (only for water exposure), blood and plasma vitellogenin concentrations were quantified using indirect endpoints, i.e.