T Jager

..caliginosa, as well as to those in the field-collected worms. Nevertheless, E. andrei accumulated slightly more than the other species and appeared to be more sensitive to the conditions in soil from one of our sites...

..The rate constant across the skin decreases with K(ow) but was generally higher than data derived from water-only exposure. The relationship with hydrophobicity was less clear for the rate constant across the gut wall...

..As the analysis is process based, population responses under food limitation can be explored, which depends critically on the selected mode of action...

..We observed thatthe no-effect concentration estimated from the receptor model is basically identical to the value from standard DEBtox, illustrating the robustness of this summary statistic...

..This discussion is illustrated with effects data for Daphnia magna, analyzed by the DEBtox model...

..It appears that CPF interacts with senescence by increasing oxidative damage. This assumption fits the data well, but has little consequences for the predicted response at the population level...

..Different modes of action resulted in different patterns in the parameter estimates, and therefore, the toxicity data by themselves reveal insight into the actual mechanism of toxic action...

..We illustrate our method with the interpretation of partial life-cycle data for two polycyclic aromatic hydrocarbons in Daphnia magna...

..The DEB3 model allows for a completely consistent assessment of toxic effects and therefore greater confidence in extrapolating, but poses greater demands on the available data...

..The model is particularly useful when the organism's food source is specifically contaminated and EP cannot be applied...

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..Hence it is a powerful tool to link the chemical and ecological status of surface waters...

..A semi-mechanistic approach yielded further evidence of pore water-related uptake, modulated by competition between H+ and metal ions at the active sites of the membranes...

..candida), although a reduction of uncertainties in metal risk assessment can be reached by consistent use of body residues rather than external concentrations...

..We expect this approach to help in identifying key mechanisms and enable to focus further research in cooperation with modelers and experimentalists to improve our understanding of the mechanisms underlying mixture toxicity...

..Furthermore, representatives of EU Member States and the chemical industry were interviewed to find out their views on applying uncertainty analysis to risk assessment of industrial chemicals...

..Given the fact that toxicity data for single compounds show clear patterns in time, it is to be expected that effects of mixtures will also be strongly dependent on time. The few examples that have been published support this statement...

..We illustrate the methods using data on daphnids and molluscs...

..The strength of the theory is in the combination of why metabolic transformation depends both on the BCF and the body size. We illustrate the application of the theory with several data sets from the literature...

..However, risk assessment can conservatively rely on equilibrium partitioning, but accurate prediction requires quantification of the kinetics of bioavailability...

..The simulation showed that due to the combined effect of the compounds in the mixture effects can be seen at very low concentrations...

..The daphnia data showed less scatter than the fish data, possibly due to the small variance in body sizes, since elimination rates are inversely proportional to body length. The square root relationship fitted these data best...

..Instead, we recommend that a critical assessment of the endpoints of determination become the basis for a need-specific monitoring strategy...

..It is concluded that the RIRA has a higher discriminative value and yields more information compared to the PTB-criterion...

..The proposed approach has potential for predicting toxicity for untested species-compound combinations; however, there is a need for a better definition of 'mode of action' in ecotoxicology...

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..These results show that measuring concentrations of hydrophobic chemicals in a PDMS-coated fiber represents a simple tool to estimate internal concentrations of chemicals in biota exposed to soil...

..Sample calculations indicate that the proposed method may provide a good alternative for currently applied methods for initial risk assessment, particularly if few toxicity data are available...

..This highlights the importance of the interactions between a chemical and the biological characteristics of the organism in determination of the resulting physiological modes of action...

..This study implies that the effect of pesticide application in the field depends on the trophic state of the receiving water body, but also that full recovery of survivors is possible after FV application...

..The interpretation of the results from toxicity tests can be improved through process-based modeling, as demonstrated on the current data set...

..These characteristics appear as similarities among multivariate functions as derived for the beetle...

..This information can be used by sewage treatment plant managers to decide whether the microbial biodegradation activity itself or the desorption from organic carbon to the aqueous phase should be improved...

..Since temperature has such a major impact on toxicity, a temperature correction may be necessary when translating toxicity data from the laboratory to the field...