We are happy to announce that our colleague, Jonathan De Raedt, defended his dissertation to earn his doctoral degree on March 7, 2019! During his PhD, his research focused on the combined effects of dispersal and chemical stressors on algae communities.
Congratulations, Jonathan! We wish you the best of luck in all your future endeavors, wherever these may take you!
Recent studies have shown that toxicity of metals to Daphnia magna depends on the temperature. In a population experiment, we investigated if the effect of temperature on nickel (Ni) sensitivity observed on the apical level can be extrapolated to the population level. However, we observed no consistent population-level effects of Ni at concentrations that significantly affected reproduction. An individual-based model (IBM) with the dynamic energy budget (DEB) theory for Daphnia magna was calibrated based on Ni toxicity data at three temperatures (15, 20 and 25°C). Using the model, we confirmed the unexpected absence of Ni effects at the population level.
Over the past decade, significant advances have been made to unravel molecular mechanisms of stress response in different ecotoxicological model species. Within this study, we focus on population level transcriptomic responses of a natural population of Daphnia magna to heavy metals. We aim to characterize the population level transcriptomic responses, which include standing genetic variation, and improve our understanding on how populations respond to environmental stress at a molecular level.
The laboratory of Environmental Toxicology and Aquatic Ecology, Environmental Toxicology Unit - GhEnToxLab (Ghent University) is looking for a full time Scientific Researcher.
1-year research project: Population models to improve ecological risk assessment of nickel
Sea spray aerosols (SSAs) have profound effects on our climate and ecosystems. They also contain microbiota and biogenic molecules which could affect human health. Yet the exposure and effects of SSAs on human health remain poorly studied. Here, we exposed human lung cancer cells to extracts of a natural sea spray aerosol collected at the seashore in Belgium, a laboratory-generated SSA, the marine algal toxin homoyessotoxin and a chemical inhibitor of the mammalian target of rapamycin (mTOR) pathway.
In this study we developed a novel, mechanistic model where we predict effects of Cu on aquatic invertebrate populations (Lymnaea stagnalis – the great pond snail). Lymnaea stagnalis is particularly sensitive species to various metals
and the precise mechanism for metal toxicity for this species are not fully understood. In this research, we extrapolated Cu toxicity effects from various studies and food sources to the population level. To improve inter-study comparability, we used a biotic ligand model to correct for the water chemistry. At the population level, the range in EC10 decreased significantly compared at the individual level. This model is the first developed at Arche Consulting and the University of Ghent where we promote the use of ecological models for the risk assessment of chemicals.