Ecological effects testing under the Toxic Substances Control Act: Acrylamide

Analysis of acrylamide aquatic toxicity data submitted under section 4 of the Toxic Substances Control Act revealed that for acute toxicity studies with bluegill, fathead minnow, and rainbow trout, concentrations of acrylamide necessary to produce 50% mortality decreased by 50-70% as a function of increasing exposure from 1 to 4 days. Analysis of acute toxicity data for Mysidopsis bahia suggested that increases in mortality with increased exposure to acrylamide might also be observed in saltwater organisms. Ratios of acute (4-day) LC₅₀ values to chronic (28-day) maximum acceptable toxic concentrations for this saltwater invertebrate were 26 for parent and offspring survival, 115 for female dry weights, and 975 for male dry weights. These ratios illustrate that long-term acrylamide exposure to sensitive life stages of M. bahia produced adverse effects on reproduction and growth at acrylamide concentrations significantly lower than those suggested by acute LC₅₀ or EC₅₀ values.