PESTICIDES AND OTHER ORGANIC MICRO POLLUTANTS IN THE RIVER ELBE

The main components of organic micro pollution regularly found in the river Elbe, belong to the wide spectrum of pesticides, nitro and chlor o benzenes and the chelating agents, especially ethylenediaminetetraac etic acid (EDTA). The level of organic micro pollution with pesticides and the other organic micro pollutants in the upper and middle reache s of the river Elbe between Schmilka and Wittenberge was determined ov er a period of nearly three years. Four sample preparation methods (SP E: solid-phase extraction and LLE: liquid-liquid extraction both with and without derivatization) have been used to analyze a wide spectrum of pesticides with different polarities by GC/ECD, NPD and MS. The pes ticide pollution caused by the triazines decreases significantly from 0.35 mu g/l (mean value) in 1992 up to 0.15 mu g/l (mean value) in 199 4. The correlation with the river water Row shows the diffuse characte r of the triazine input. In the last year of the pesticide screening a change to the more polar substances such as phenoxyalkanoic acid and nitrophenol pesticides as well as chloralkanoic acid pesticides have b een noticed. The origin of trichloroacetic acid (TCA) can be explained by the waste influence, supported by the good correlation of the TCA course with the chloroform concentrations determined.