Toxicogenomics

In this ecotoxicological study, the biological effects of a major class of environmental pollutants are studied using a systems biology approach, assessing these effects across different levels of bio

During recent years ecotoxicology has been an emerging field and its experimental focus has been expanded from using mainly chemical stressors (e.g. cadmium) to assessing the effects of natural or non-chemical stressors (e.g.

Over the last decade, increasing concern has been raised towards the potential of a diversity of environmental compounds to interfere with the endocrine system of humans and wildlife. Given the ubiquitous presence of these ‘endocrine disrupting chemicals’ (EDCs) in the aquatic environment – often at high concentrations – fish are inevitably exposed, resulting in a variety of adverse biochemical, physiological and reproductive effects, as demonstrated by researchers worldwide.

Abstract

This study investigates the importance of water and food as exposure sources of three model contaminants with different physico-chemical properties and modes of action to zebrafish. It is explored to what extend uptake via water or food results in different responses and toxic effects. The responses and effects are studied at molecular, cellular and organismal level using genomics, proteomics and physiological approaches. The project aims to provide a in depth understanding of how different substances interact with a model system taking into account key factors such as developmental stage, exposure route and exposure time. The results of the genomics and proteomics analysis should considerable enlarge our understanding of the molecular mechanisms of toxicity and defense.

Daphnia magna, a frequently used standard organism in laboratory toxicity testing was chosen for this study. In laboratory toxicity testing it is often assumed that organisms will respond in a similar manor as in a field situation. However, in realistic environments multiple factors and stressors, such as the differences in temperature, food availability, etc.... may strongly interfere with responses to pollutant stress. Moreover, organisms are almost always exposed to mixtures of chemical stressors in natural situations. From a toxicological point of view, these interactions can highly influence the overall impact of chemical stressors.