Pesticide residues in biological waste

The aim of this study was to detect crop protection products (CPP) in single fractions of biological waste and to estimate pesticide concentrations in biological waste, depending on its composition. The composition of biological waste was determined from the literature, which provided information on its local and seasonal variability. The residue analysis included 17 pesticides for the analysis of tropical fruit peels and 48 pesticides for other fractions, e.g. vegetables, other fruits and ornamental flowers. The freeze-dried samples were extracted ultrasonically and purified by means of gel permeation chromatography. The analysis was carried out using gas chromatography with a mass selective detector in the selected ion monitoring mode. All tropical fruit peels contained CPP-residues. Thiabendazole was the most important contaminant with respect to the concentration and frequency of occurrence. The vegetables, other fruits and flowers also contained CPP-residues, such as the fungicides captan and dodemorph and the insecticide endosulfan. Based on import data and the composition of biological waste, the CPP-content of biological waste was estimated for rural and urban areas in summer and winter. Due to the higher percentage of tropical fruit peels, thiabendazole was the main contaminant in winter. The total concentration of CPP, summed up over all substances, ranged between 828 and 1829 μg (kg ww)−1.