Drs. J. Baas

Room: T528
Phone: 020-5987128
Email: jan.baas@falw.vu.nl
Curriculum vitae: 1965/02/11: born, Huizen
1990/05/15: Master's chemisty, Amsterdam
Specialization: Anorganic & environmental chemistry
Project: Toxicity of mixtures of compounds
DEB tele course

Effects of mixtures of compounds

Current risk assessment is based on the effects of single compounds, but organisms are subjected to numerous chemicals with a variety of effects. This combined exposure may cause effects that are not expected when only individual compounds are considered. For instance in "het Westland" an agricultural area in the Netherlands of about 100 km2 where almost 50 % of the surface is built with greenhouses a variety of pesticides is found in surface waters. Often all individual compounds are found below their environmental safety level, and so classical risk assessment (based on individual compounds) tells that there are no effects to be expected. Still the biological diversity in these surface waters may be quite different from comparable surface waters in nearby parts of the Netherlands. In addition to this it is now estimated that 25 till 33 % of the burden of disease in the industrialized western countries can be attributed to long term exposure to low concentrations of complex mixtures of compounds.

This leads to the conclusion that classical risk assessment does not have a good answer to the combined toxicity of compounds at relatively low concentration levels. To improve the current situation, the EU commissioned a project with the aim to make more realistic risk assessment, based on the simultaneous exposure to different chemicals.

The work that will be done at our laboratory is part of a very large research project in which 38 research groups in Europe are working together. The whole project is split in four subjects:

Our research is focused on risk assessment. In our laboratory we will model the effects of different toxicants (sets of two toxicants and mixtures of many different toxicants) on different organisms. Our modeling work will be carried out in a close collaboration with the other research groups, especially with the research groups working on effect assessment.

Jan has 4 highligthed articles among the 14 publications of this project: BaasJage2009a BaasWill2009 BaasKooy2010 JageVand2010

The NoMiracle leadership exposed this application of DEB research as being of high relevance to European Environmental Policy

This is the symposium that concludes my project

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