Department Environmental Toxicology

Micropollutant-effect relationships linked to water treatment

Utox is involved in the EcoImpact research effort. The project ERAfresh (funded by FOEN) aims at analyzing causal relationships between micropollutants (MP) in freshwaters and the health status of periphyton communities. Assessment of periphyton tolerance towards MP were carried out at various waste water treatment plants (WWTP). Downstream communities generally showed site-specific increased phototrophic and/or heterotrophic tolerance compared to upstream communities, demonstrating causal links between the occurrence of MP and structural and functional changes in periphyton These findings also give a first indication on the MP composition in the effluents (i.e. dominance of herbicides or bactericides).
A pilot study aiming to compare the health and biochemical state of fish up- and downstream of WWTP (Utox/EcotoxCentre co-financed) will be finalized in spring 2015 after repeated sampling, including before and after WWTP shut-down. Results thus far demonstrate i) that response profiles in fish reflect chemical mixtures identifiable in the effluent and ii) that the developed sampling and analysis methodology is robust. Results led to significant funding by FOEN for 2015/2016 to probe different EcoImpact sites.
In collaboration with W&T, FOEN and an American research team, we have finalized several studies on the role of advanced oxidation processes in the evolution of toxicity (such as mutagenicity and estrogenic activity) of priority chemicals and effluents. A conceptual framework paper has just been accepted in Water Research (corresponding author: von Gunten).