Microcyclops sp. was exposed to selected detergents (two dishwasher detergents, one washing-powder, one washing-machine powder and one shampoo) for 24 hours. The results indicated the dishwasher powder had higher lethal effect on Microcyclops sp. than the other examined detergents, especially one containing 17% Linear Alkyl Benzene Sulfonate, 5% Di-Ethanolamine and 2% Lauric Acid. The permissible concentration and the LC50 for the dishwasher powder is 7.84 and 13.32 mg/l respectively. Among the powders the washing-machine powder appeared to be least lethal (LC50 = 43.87 mg/l) and the shampoo with LC50 of 47.27 mg/l had the lowest lethal effect on Microcyclops sp.. Correlation rate of the detergent concentration logarithm and the mortality of Microcyclops sp. ranged between 94-98%......
)