Biological Test Method: Test for Survival and Growth in Sediment and Water Using the Freshwater Amphipod Hyalella azteca

Revised methods now recommended by Environment Canada for performing sediment and water-only toxicity tests using the freshwater amphipod Hyalella azteca are described in this report. The endpoints for these tests are survival and dry weight of amphipods at the end of a 14-day test. This revised version of Report EPS 1/RM/33 includes numerous updates such as options for sediment-to-water ratio, age of test organisms used to start a test, use of replicates, overlying water renewal, food types and feeding rates, and light intensity for culturing, as well as the statistical analyses of data. Procedures for a water-only survival and growth toxicity test using Hyalella azteca have also been included herein. This revised method supersedes Environment Canada's test for survival and growth in sediment using Hyalella azteca, which was published as Report EPS 1/RM/33 in December 1997. The sediment test is intended primarily for measuring the adverse effect(s) of freshwater sediments, although procedures for testing estuarine sediments (≤15‰ salinity) are also described.