Effects of dietary exposure to the pyrethroid pesticide esfenvalerate on medaka (Oryzias latipes)

The pyrethroid insecticide esfenvalerate is widely used on orchard crops throughout California. In the aquatic environment, this compound is likely to accumulate in sediments, food particles and benthic organisms due to its lipophilicity and environmental persistence. This pilot project tested the hypothesis that esfenvalerate is toxic to medaka (Oryzias latipes) when taken up with the diet. For 7 days fish were fed diets, which contained esfenvalerate in three different concentrations (4, 21, 148 mg/kg, measured). Endpoints measured were mortality, fecundity, fertilization and hatching success of embryos, viability of larvae and cellular stress protein (hsp60, hsp70, hsp90) levels. The toxicity of aqueous exposure of medaka to esfenvalerate was also determined. Whereas the 96-h LC50 in the aqueous exposure was <9.4 microg/l, the dietary exposure did not cause mortality. Possible effects of dietary esfenvalerate were seen on fertilization and hatching success and the number of non-viable larvae. Expression of hsp60 and hsp90 showed a dose-dependent response pattern.     

Effect of oxygen fugacity and water on phase equilibria of a hydrous tholeiitic basalt

The influence of oxygen fugacity and water on phase equilibria and the link between redox conditions and water activity were investigated experimentally using a primitive tholeiitic basalt composition relevant to the ocean crust. The crystallization experiments were performed in internally heated pressure vessels at 200 MPa in the temperature range 940–1,220°C. The oxygen fugacity was measured using the H₂-membrane technique. To study the effect of oxygen fugacity, three sets of experiments with different hydrogen fugacities were performed, showing systematic effects on the phase relations and compositions. In each experimental series, the water content of the system was varied from nominally dry to water-saturated conditions, causing a range of oxygen fugacities varying by ~3 log units per series. The range in oxygen fugacity investigated spans ~7 log units. Systematic effects of oxygen fugacity on the stability and composition of the mafic silicate phases, Cr–spinel and Fe–Ti oxides, under varying water contents were recorded. The Mg# of the melt, and therefore also the Mg# of olivine and clinopyroxene, changed systematically as a function of oxygen fugacity. An example of the link between oxygen fugacity and water activity under hydrogen-buffered conditions is the change in the crystallization sequence (olivine and Cr–spinel) due to a change in the oxygen fugacity caused by an increase in the water activity. The stability of magnetite is restricted to highly oxidizing conditions. The absence of magnetite in most of the experiments allows the determination of differentiation trends as a function of oxygen fugacity and water content, demonstrating that in an oxide-free crystallization sequence, water systematically affects the differentiation trend, while oxygen fugacity seems to have a negligible effect.     

The influence of the void fraction on the particle migration: A coupled computational fluid dynamics–discrete element method study about drag force correlations

Granular soils subjected to flow through their soil skeleton can show a behaviour in which fine particles migrate through the pore space between coarser particles. This process is called internal instability or suffusion. This contribution deals with the numerical analysis of the migration of fine particles in a soil column subjected to fluid flow with unresolved coupled computational fluid dynamics–discrete element method (CFD–DEM) with special regards to the used drag force correlation. The contribution investigates the influence of the Schiller–Naumann model and its extension with a voidage term on the migration behaviour of fine particles. The voidage term is further varied with a parameter, which controls the impact of the change of the void fraction on the drag force. It could be observed that the Schiller–Naumann model does not yield in a suffusive behaviour while the extended models show significant particle migration. Thereby, increasing the impact of the void fraction on the drag force results in stronger particle migration. These results reveal the need for good validation techniques. They indicate how the drag force correlation can be adapted to depict the correct particle migration behaviour.     

Bioassay‐directed fractionation for analyzing estrogens in surface waters of the German Baltic Sea

A reversed‐phase fractionation method with subsequent biological and chemical analysis has been developed to estimate the contributions of the most potent estrogens to observed estrogenic effect potentials. Surface water samples were taken in the German Baltic Sea (Inner Wismar Bay and Darss Peninsula, sampling campaign July 2003) and were separated into seven individual fractions. Three fractions showed significant estrogenic activities and clear dose‐dependant responses were obtained in the yeast estrogen screen (YES). In the 2nd fractions liquid chromatographic‐electrospray‐tandem mass spectrometric (LC‐ESI‐MS‐MS) analyses showed the presence of bisphenol A (Inner Wismar Bay: 4.8 ng L^–1 and 6 ng L^–1; Darss Peninsula: 0.91 ng L^–1 and 1.7 ng L^–1) and ethinylestradiol (Inner Wismar Bay: 2.0 ng L^–1 and 6.0 ng L^–1; Darss Peninsula: < MDL and 1.7 ng L^–1), whereas estrogenic activities in the YES were only around 10% of the positive control E2. Although not identified prior in the total extract the natural hormones estradiol (Inner Wismar Bay: 0.13 ng L^–1 and 0.19 ng L^–1; Darss Peninsula: 0.12 ng L^–1 and 0.16 ng L^–1) and estriol (Inner Wismar Bay: < MDL and 0.33 ng L^–1; Darss Peninsula: < MDL) could be detected in the 3rd fractions, where high estrogenic potentials could be observed. The 4th fractions showed high responses as well and estrone were herein quantified with concentrations of 0.16 ng L^–1 and 0.18 ng L^–1 (Darss Peninsula) up to 0.37 ng L^–1 (Inner Wismar Bay). Measured and calculated estradiol equivalents for individual fractions correlated very well (R² = 0.78), when disregarding results of the 2nd fraction, where high deviations occurred.     

Production of Drinking Water from Highly Contaminated Surface Waters: Removal of Organic,Inorganic, and Microbial Contaminants Applying Mobile Membrane Filtration Units

In military out of area missions of the Bundeswehr, it can be necessary to produce drinking water even from highly polluted surface waters containing a variety of organic, inorganic, and microbiological contaminants. Thus, mobile drinking water purification systems must be able to remove such contaminants as far as possible to meet the requirements of the German and European drinking water regulation/directive. Presently, two novel drinking water purification units applying membrane filtration undergo intensive long‐term trials carried out by the Bundeswehr. If these trials positively proof the functionality of these units and their ability to remove all possible contaminants they shall substitute so far available devices which use large amounts of chemicals and charcoal filtration for water purification.In the course of a research project, the functionality of the new devices and their efficacy to remove high amounts of algae, microbes, and organic and inorganic pollutants are additionally tested in “worst‐case” field studies. In September 2000, the first mobile drinking water purification unit was tested at the Teltowkanal in Berlin, Germany.This canal was chosen because it carries high burdens of municipal sewage effluents. The results from the fatigue test confirmed the ability of the water purification unit to reduce the concentrations of all contaminants meeting the maximum tolerance levels set by the German/European drinking water regulation.The pre‐filtration device was very effective in removing algae and solid particles to protect the membranes from clogging and to enable an almost maintenance‐free operation. Residues of pharmaceuticals and some other organic contaminants have almost totally been removed from the surface water where they were detected at individual concentrations up to the μg/L‐level.     

Statistical Classification of Different Petrographic Varieties of Aggregates by Means of Near and Mid Infrared Spectra

The increasing interest of the construction aggregates industry in reducing production costs and the costs resulting from improper use of construction materials leads to the question whether it is possible to statistically identify some rock variants by their reflectivity of near-infrared and mid-infrared light. Infrared spectroscopy allows quantitative and qualitative analysis of minerals in a reliable manner, whereas the classification of rocks is complicated by the fact that the optic behavior of minerals forming the rock often appears muted. In addition, minor constituents may dominate the spectrum. Furthermore the relevant spectra form high dimensional data, which are extremely difficult to analyse statistically, especially when curves are very similar. Common methods of multivariate statistics for this type of data, used in chemometric studies, followed by linear discriminant analysis, do not lead to acceptable classification error rates. In this paper wavelets are used in order to reduce dimensionality. As wavelets are better able to mirror local behavior of curves, they are more suitable for selecting characteristic features. The approximation is analyzed in terms of its classification properties using Mahalanobis distance or flexible discriminant analysis.     

Application of sequence stratigraphic concepts to the Upper Cretaceous Tununk Shale Member of the Mancos Shale Formation,south-central Utah: Parasequence styles in shelfal mudstone strata

Although sequence stratigraphic concepts have been applied extensively to coarse-grained siliciclastic deposits in nearshore environments, high-resolution sequence stratigraphic analysis has not been widely applied to mudstone-dominated sedimentary successions deposited in more distal hemipelagic to pelagic settings. To examine how sequence stratigraphic frameworks can be derived from the facies variability of mudstone-dominated successions, the Tununk Shale Member of the Mancos Shale Formation in south-central Utah (USA) was examined in detail through a combination of sedimentological, stratigraphic and petrographic methods. The Tununk Shale accumulated on a storm-dominated shelf during the second-order Greenhorn sea-level cycle. During this eustatic event, the depositional environment of the Tununk Shale shifted laterally from distal middle shelf to outer shelf, then from an outer shelf to an inner shelf environment. At least 49 parasequences can be identified within the Tununk Shale. Each parasequence shows a coarsening-upward trend via upward increases in silt and sand content, thickness and lateral continuity of laminae/beds, and abundance of storm-generated sedimentary structures. Variations in bioturbation styles within parasequences are complex, although abrupt changes in bioturbation intensity or diversity commonly occur across parasequence boundaries (i.e. flooding surfaces). Due to changes in depositional environments, dominant sediment supply and bioturbation characteristics, parasequence styles in the Tununk Shale show considerable variability. Based on parasequence stacking patterns, eleven system tracts, four depositional sequences and key sequence stratigraphic surfaces can be identified. The high-resolution sequence stratigraphic framework of the Tununk Shale reveals a hierarchy of stratal cyclicity. Application of sequence stratigraphic concepts to this thick mudstone-dominated succession provides important insights into the underlying causes of heterogeneity in these rocks over multiple thickness scales (millimetre-scale to metre-scale). The detailed sedimentological characterization of parasequences, system tracts and depositional sequences in the Tununk Shale provides conceptual approaches that can aid the development of high-resolution sequence stratigraphic frameworks in other ancient shelf mudstone successions.     

Effect of water on tholeiitic basalt phase equilibria: an experimental study under oxidizing conditions

To investigate the effect of water on phase relations and compositions in a basaltic system, we performed crystallization experiments at pressures of 100, 200 and 500 MPa in a temperature range of 940 to 1,220°C using four different water contents. Depending on the water activity, the oxygen fugacity varied between 1 and 4 log units above the quartz-magnetite-fayalite buffer. Addition of water to the dry system shifts the solidus > 250°C to lower temperatures and increases the amount of melt drastically. For instance, at 1,100°C and 200 MPa, the melt fraction increases from 12.5 wt% at a water content of 1.6 wt% to 96.3% at a water content of 5 wt% in the melt. The compositions of the experimental phases also show a strong effect of water. Plagioclase is shifted to higher anorthite contents by the addition of water. Olivine and clinopyroxene show generally higher MgO/FeO ratios with added water, which could also be related to the increasing oxygen fugacity with water. Moreover, water affects the partitioning of certain elements between minerals and melts, e.g., the Ca partitioning between olivine and melt. Plagioclase shows a characteristic change in the order of crystallization with water that may help to explain the formation of wehrlites intruding the lower oceanic crust (e.g., in Oman, Macquarie Island). At 100 MPa, plagioclase crystallizes before clinopyroxene at all water contents. At pressures > 100 MPa, plagioclase crystallizes before clinopyroxene at low water contents (e.g. < 3 wt%), but after clinopyroxene at H₂O in the melt > 3 wt%. This change in crystallization order indicates that a paragenesis typical for wehrlites (olivine–clinopyroxene–without plagioclase) is stabilized at low pressures typical of the oceanic crust only at high water contents. This opens the possibility that typical wehrlites in the oceanic crust can be formed by the fractionation and accumulation of olivine and clinopyroxene at 1,060°C and > 100 MPa in a primitive tholeiitic basaltic system containing more than 3 wt% water. The comparison of the experimental results with evolution trends calculated by the thermodynamic models “MELTS” and “Comagmat” shows that neither model predicts the experimental phase relations with sufficient accuracy.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.