Professor, University of Minnesota, Minneapolis, MN
Senior scientist, U.S. Environmental Protection Agency, Environmental Research Laboratory—Duluth, Duluth, MN
Pages: 7 Published: Jan 1985
The objectives of this analysis of the Mount-Norberg Ceriodaphnia toxicity test were to improve its application to specific ecosystems and to shorten the duration required to obtain significant results. The three-brood seven-day toxicity test using Ceriodaphnia grown at 25°C became a 28-day test at 18°C. Using typical ecosystem temperature is an important aspect of this test when applied to specific locations. Generally Ceriodaphnia can be grown at temperatures of 12 to 25°C; too few neonates were produced at 6°C for useful test results. The synchronous release of neonates by parthenogenic females may be used in determining when to sample offspring and thus reduce the cost of testing complex effluents. The intrinsic growth rate r of these animals may be used instead of their net reproductive rate Ro to provide answers in a shorter time, with smaller coefficients of variation.
invertebrates, toxicity, aquatic biology, toxicity tests, Ceriodaphnia, growth rates, reproductive rates, duration
Paper ID: STP33588S