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R9 Laboratory SOP 1022
GREEN ALGA, SELENASTRUM CAPRICORNATUM GROWTH TEST
Summary
This SOP describes procedures for testing the short-term adverse effects of potentially contaminated freshwater solutions, during a static 4-day exposure. This SOP has been written following the method outlined in the USEPA manual, Short-Term Methods For Estimating The Chronic Toxicity Of Effluents And Receiving Water To Freshwater Organisms, Third Edition, July 1994, EPA/600/4-91/002.
This procedure is applicable to waters containing most chemicals, either singly or in formulations, commercial products, and known or unknown mixtures.
The relative toxicity of fresh waters can be determined through a 4-day static test in 125 mL glass flasks. The response of the population is measured in terms of changes in cell density, chlorophyll content or absorbance. The response of selenastrum to the test solutions are compared with the response in the control water. A negative control or reference test is used to provide (A) a measure of the acceptability of the test by providing evidence of the health and relative quality of the test organisms, and the suitability of the overlying water, test conditions and handling procedures, etc., and (B) the basis for interpreting data obtained from the test solutions.