Reproducibility of short-term and reproduction toxicity experiments with Daphnia magna and comparison of the sensitivity of Daphnia magna with Daphnia pulex and Daphnia cucullata in short-term experiments

The reproducibility of short-term toxicity tests with Daphnia magna was checked using 15 different organic compounds in three different laboratories, with satisfactory results; the same group of compounds was used to compare the sensitivity of three daphnid species, all of which showed approximately the same order of sensitivity, although variations not exceeding a factor of 6 were obtained in the LC50 value in a few instances. The results of reproduction (chronic) toxicity studies with Daphnia magna showed that these may be easily performed within 3 weeks, duplicate experiments being necessary to obtain an approximate no effect level.