Cooperation for an effect-based investigation of municipal waste waters

Its not happening often that ecotoxicologists are asked by a municipality to investigate their sewage waters. The City of Stolberg together with Wasserverband Eifel-Rur (WVER) did, and we agreed to give 10 samples from their sewage water system a thorough ecotoxicological look, including influents and effluents from the waste water treatment plant Stolberg-Steinfurt.

This small but very interesting project will be covered by the master's thesis of candidate Sarah Johann. We will apply a range of different bioassays to reveal any possible hazardous potential.
Stolberg is a city near Aachen and an industrial hotspot of the region. While they have extensive data on heavy metal concentrations from continuous monitoring, so far no in-depth investigation of organic contamination has been done. Our bioassays are very well suited and sensitive enough to detect such substances through their biological activity.

Any positive results we will gain do not necessarily indicate a problem at all. Concentrations traceable using bioassays are often well below any environmentally or even toxicologically relevant level. Also, we do not expect any severe findings. This is a completely unbiased study, driven by scientific curiosity.

The City of Stolberg and the WVER are just very strict regarding environmental and human safety. They do so much for quality assurance when it comes to their waste waters, they now also want to cover this aspect. For us the project is a fantastic opportunity to get access to well-defined, specific waste water samples from different, very interesting spots, to better understand distribution of contaminants along the sewage water flow, and to prove bioassays as valuable tools for waste water monitoring.

Water to the power of 3 - Quality, Security and Management

The W3-Hydro project ("Water Quality Event Detection for Urban Water Security and Urban Water Management Based on Hydrotoxicological Investigations") is a BMBF-funded collaboration between RWTH Aachen University and the Technion in Haifa, Israel, within the Joint German-Israeli Water Technology Research Program. The project is coordinated by the Institute of Hydraulic Engineering and Water Resources Management (IWW) under the lead of Prof. Holger Schüttrumpf.

We aim at an early event detection, identification and management of unforeseen, negative and sudden events for drinking water supply using hydrological in combination with ecotoxicological experimental investigations, together with water management and modelling.

Our part is (a) to develop an early warning system that automatically triggers sampling and further testing based on biotest systems, and (b) to investigate contaminant behaviour in the water-sediment-system for better understanding of substance transport and distribution.

We already built a custom-made low-cost pipetting robot for the automatic sampling, and started with the development of a flow-through device for behaviour monitoring of zebrafish larvae.

Futher info on the project can be found at http://w3hydro.org/

And again, I could enjoy designing a logo.

PAHs from coals are ecotoxicologically active

In continuation of the PAHs-from-coals-story, Wiebke Meyer published additional data and findings on the toxic potential of PAHs deriving from different coal types in the journal Science of the Total Environment.

The article titled "Polar polycyclic aromatic compounds from different coal types show varying mutagenic potential, EROD induction and bioavailability depending on coal rank" reports on mutagenicity and dioxin-like activity of coal-derived PAHs. Wiebke found that the toxic properties differ between coal types, and also some are better available to organisms than others, thus might more likely cause adverse effects.

Constant dosing: reliable exposure concepts to reduce "animal" use

Passive dosing is an approach were the partitioning equilibrium of a substance between a solid and a liquid phase is utilised to maintain exposure concentrations in biotesting. This means that test organisms are exposed at defined and constant concentrations, thus reducing experimental variability and uncertainty, which leads to more robust results.

Together with Philipp Mayer and Kilian E.C. Smith, both formerly of NERI in Roskilde, Denmark, and now with Technical University of Denmark and KIST Europe, respectively, we put out a paper "PAH toxicity at aqueous solubility in the fish embryo test with Danio rerio using passive dosing" in Chemosphere reporting on the usage of PDMS cast into glass vials for passive dosing of non-hatched zebrafish embryos (FET biotest). We show for 10 PAHs constant delivery from the PDMS reservoir to the water phase based on equilibrium partitioning, and prove passive dosing applicable in FET. This test design could in future lead to better data and hence reduced use of zebrafish embryos, albeit legally fish larvae up to 120 hours post fertilization are not considered animals. But we are biologists, we care about any organism.