The use of juvenile mussels, Utterbackia imbecillis Say (Bivalvia: Unionidae) as a standardized toxicity testing organism

Toxicity testing with juvenile mussels, particularly Utterbackia imbecillis, has increased in recent years. However, standardized culture and testing procedures have not been established, and several issues associated with toxicity testing have not been fully investigated. This research addresses some of these issues regarding juvenile U. imbecillis. When the influence of age on metal toxicity was investigated, results showed no significant differences in toxic response of 2, 9, and 16d juveniles to cadmium (Cd) in repeated tests. Variability in mortality data observed with older juveniles in copper (Cu) and Cd tests appeared to be correlated with differences in diet prior to testing. Because tissue culture techniques are used to obtain U. imbecillis juveniles, sensitivity of juveniles metamorphosed on a natural fish host was determined. No statistically significant differences existed in metal sensitivity of naturally-versus artificially-cultured mussels. Mean 48-h Cu and Cd LC50 values for juveniles obtained by the tissue culture procedure were 76 and 59...