Sublethal effects of cadmium on the energetics of a tropical freshwater snail, brot/a hainanensis (brot, 1872)

An increase in cadmium concentrations resulted in a significant reduction in the consumption rates, absorption rates, and scope for growth (SfG) in Brotia hainanensis. There was, however, no significant change in the amount of energy lost in respiration. The no observed effect concentration and lowest observed effect concentration for cadmium were 0.4 and 0.8 mg/L, irrespective of whether consumption rates, absorption rates, or scope for growth were used as the end point. Results suggested that the SfG assay could be simplified by (1) focusing on the measure of consumption rates as a performance indicator, and (2) shortening the exposure duration from seven to four days. This technique showed great potential as an ecotoxicological assessment tool for tropical lotie waters. The benefits and potential problems associated with the SfG assays are discussed.