Toxicogenomics

During the production and after therapeutic use pharmaceutical compounds can enter the aquatic environment through industrial and household discharges. Indeed, pharmaceuticals are continually released into the environment wherever humans live. But until recently, very little attention has been paid on what happens to these these compounds after their administration or use. Human pharmaceuticals have ‘enjoyed’ several decades of unrestricted discharge to the environment. Over the last decade, the increasing number of reports on the occurrence of human pharmaceuticals in the aquatic environment has raised public concern on the environmental risk of these compounds. The big unknown however, is whether the presence of low concentrations of human pharmaceuticals in the aquatic environment can cause a serious threat. Currently, very little is known on the potential adverse effects of human pharmaceuticals on aquatic organisms, and there is a great need for relevant and specific ecotoxicological effect data in order to correctly assess the environmental risk of pharmaceutical compounds.

The number of chemical products produced by men is enormous. At present the number of chemicals registered by the Chemical Abstract Service exceeds 20 million. Estimations are that over 100.000 compounds are released in the environment in such volumes that they generate a potential threat for men and environment. Only little is known on the toxicological properties of this large group of chemicals. The scarce information available until now consists mainly of acute toxicity data. Long term adverse effects on populations, communities and ecosystems are poorly documented. The lack of chronic and long term data is illustrated by the phenomenon of endocrine disruption. Various chemicals are capable of interfering with the endocrine metabolism of several animal species leading to negative effects on their reproduction. There is a great deal of uncertainty about the possible adverse (endocrine disrupting) character of chemicals for men and environment due to the scarce availability of chronic toxicity data and restricted knowledge on the toxicological working mechanisms. Especially for the ecologically important group of invertebrates no clear assays for mechanistic evaluation of endocrinological pathways disruption are developed yet. It is clear that there is an urgent need for this kind of assays to provide both chronic relevant as well as mechanistic detailed data.