The project "Development of a simple technology in drinking water treatment for nitrate and pesticide removal" granted by the European Union within the program: Scientific and Technological Co-operation with the Developing Countries (INCO-DC), is a co-operation project of six Universities from Germany, Belgium, Turkey and Morocco. Objective of the project is the development of an easy to use and reliable technique for nitrate and pesticide removal in drinking water treatment. The technique is based on denitrification using biodegradable polymers as a carbon source under anoxic conditions and pesticide removal by co-metabolic biodegradation and adsorption during the denitrification processes. Within the scope of the co-operation project the Division of Water Chemistry at the Engler-Bunte-Institute (EBI) will be responsible for the coordination and performance of pesticide and nitrogen analysis and the implementation of Good Laboratory Practice and Quality Control (GLP/QC) principles. In addition studies on the adsorption characteristic of pesticides on the biodegradable polymers will be carried out at the Engler-Bunte-Institute. In 1998 we have started to develop analytical techniques for the analysis of pesticides relevant to the area of investigations in Morocco and Turkey. The analytical techniques include solid phase extraction (SPE) and gas chromatography-mass spectrometry (GC/MS). These analytical methods are also being extended for detection of metabolites of the selected pesticides. We have also started to study the sorption characteristics of the selected pesticides on PCL and PHB surfaces. The sorption characteristics are being studied under different conditions. We are systematically elucidating the influence of pH, ionic strength, temperature and biofilm growth on the adsorption of the pesticides onto the polymers.