| Abstract: | Since 1987 significant decrease of pesticide concentrations in the river Rhine has been observed. This is due to the improvement of waste water treatment processes and the closing of some pesticide production sites in the Rhine basin area. Whereas in the last years point pollution from waste water effluents was the dominant source for pesticide input into the river, nowadays the nonpoint pollution (diffuse runoff) becomes more and more important. This leads to seasonal occurrence or to higher concentration peaks after application in agriculture. Only for atrazine and its metabolite desethylatrazine very low ?background”?-levels could regularly be found along the river and all over the year. Furthermore pesticide metabolites and byproducts seem to be interesting for evaluating pesticide pollution in the river Rhine. |
