Development and validation of a Daphnia magna four-day survival and growth test method.

Zooplankton are an important part of the aquatic ecology of all lakes and streams. As a result, numerous methods have been developed to assess the quality of waterbodies using various zooplankton species. Included in these is the freshwater species Daphnia magna. Current test methods using D. magna involve acute lethality test methods ranging from 24 to 96 h in duration and chronic test methods with durations of 21 to 28 d. Whereas the current acute and chronic test methods are useful, a need exists for a shorter-duration test method that will provide a chronic or subchronic endpoint with this, species. In the present study, a 4-d, static-renewal survival and growth test was developed for use with D. magna. The test results were compared to performance criteria and results from 7-d survival and reproduction tests with Ceriodaphnia dubia to determine the level of comparability between the two methods. Results from the 4-d D. magna survival and growth test method indicated that this method will produce consistent results with various reference toxicant materials and provide data that are both reproducible and useful for detecting potential toxicity in aquatic environments.