Molecular and Cellular Toxicology

Perfluorinated organic compounds (PFOCs) are manufactured for over 50 years in enormous quantities and are used in materials such as wetting agents, foam fire extinguishers and stain resistant treatments for leather, paper and clothing. Due to their environmental persistence and tendency to bioaccumulate, the global concern for the potential toxicity of these organic compounds has strongly been rising during the last decade.

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.

Although cadmium toxicity is a well studied theme in the field of aquatic toxicology, still little is known concerning the molecular mechanisms of its toxic action. Moreover most laboratory studies only consider waterborne cadmium exposure, whereas dietary exposure can also contribute to the accumulation and effects of cadmium in fish. For a better understanding of the toxic responses leading to adverse effects there is an increasing need for more sensitive tools to determine early reactions on cadmium exposure and accumulation.