Laboratory culture of the freshwater benthic gastropod Bellamya aeruginosa (Reeve) and its utility as a test species for sediment toxicity.

This study aimed to develop original laboratory culture and sediment toxicity testing protocols for the freshwater gastropod Bellamya aeruginosa (Reeve), a new potential species for sediment toxicity testing. B. aeruginosa was successfully cultured with an effective culture system under proposed laboratory conditions. Optimal ad libitum feeding levels for larvae, juveniles, and adults were 2.0, 6.0, and 16.0 mg fish food/(snail x day), respectively. Mean survival rates of juveniles were higher than 90%. The snails could be sexed at 9 weeks of age, and their generation time is approximately 4 months. Reproduction continued all year around; the mean fecundity was 0.55 newborn/(female x day). The utility of this species for bioassays was evaluated in both 10-day and 28-day case studies with artificial sediments. The 10-day LC50 of Cu for larvae was 480 gg/g dry weight (dw), and the lowest observed effects concentration of Cu for survival and growth of larvae was 195 microg/g dw. Survival and growth are reliable indicators of acute toxicity. Larvae accumulated more Cu than adults. B. aeruginosa exhibited a higher sensitivity to Cu exposure than standard test species (Hyalella azteca and Chironomus tentans). The 28-day test of sediment toxicity with adults showed that fecundity was a robust endpoint indicator of reproductive toxicity, and the biochemical endpoints of superoxide dismutase, catalase, and glutathione could be used as sensitive biomarkers for Cu-induced oxidative damage. B. aeruginosa can be therefore recommended as a candidate for the standardization of the freshwater sediment toxicity test protocol.