ABSTRACT
Two small tributaries of the River Ruhr (Northrhine-Westphalia, FRG) were investigated to reveal sources and pathways of pesticide input. Non agricultural pesticide use contributed more than two thirds of the whole observed pesticide loads in surface water. Diuron load varied between 0.6 % and 1.2 % of the estimated annual application amount. Almost one third of Diuron input was referred to baseflow after underground passage.
