Experimental simulation of pesticide loading in a stream mesocosm

An artificial stream mesocosm was treated with a formulated 14C-pesticide in autumn 1995 simulating an overspray event. Water, sediment, algae and fish samples were taken at certain time periods and analysed for total radioactivity, test substance and main metabolites. Strengths and weaknesses of the system for providing supporting information for a detailed risk assessment are discussed.