Acute aquatic toxicity tests with acrylamide monomer and macroinvertebrates and fish

Abstract

AbstractAquatic toxicity tests were conducted to determine the acute toxicity of acrylamide monomer to two species of aquatic macroinvertebrates (48‐h LC50) and three species of fish (96‐h LC50). The test animals were daphnids (Daphnia magna), midges (Paratanytarsus parthenogenetica), rainbow trout (Salmo gairdneri), fathead minnows (Pimephales promelas) and bluegill (Lepomis macrochirus). The organisms were exposed to five concentrations of acrylamide and a control, using intermittent‐flow procedures. The proportional diluter system was calibrated and the test system equilibrated before the tests were begun. Acrylamide monomer concentrations were analytically determined at equilibration, initiation and termination of the tests.Macroinvertebrates and fishes were observed for mortality and abnormal behavior twice daily for the duration of the tests. The calculated LC50s, based on measured concentrations of acrylamide monomer, were as follows: daphnids, 160 mg/L; midges, 410 mg/L; rainbow trout, 110 mg/L; fathead minnows, 120 mg/L; bluegill, 100 mg/L. These values were three orders of magnitude higher than those concentrations previously reported to increase invertebrate mortality under field conditions. The results demonstrated that acrylamide monomer was moderately toxic to the five aquatic organisms studied, under the test conditions utilized.