Bioaccumulation and toxic effects of cadmium on feeding and growth of an Indian pond snail Lymnaea luteola L. under laboratory conditions

Abstract

Effects of dissolved cadmium exposure on the survival, feeding, growth rates and accumulation in Indian pond snails Lymnaea luteola L. were examined for a period of 7 weeks. The concentrations of cadmium tested were 0, 10, 32, 100, 320, 560, and 1000 μg l −1. Cadmium exposure significantly inhibited the feeding and growth rates. At higher Cd concentrations snails refused to consume food offered as plant Marsilia sp. leaves. Cadmium mainly accumulated in soft tissues in a dose-dependent manner. After 4 and 7 weeks of exposure, the no observed effect concentration (NOEC) of Cd was 10 μg l −1 and the lowest observed effect concentration (LOEC) was 32 μg l −1. Reduction of growth (decrease in wet weight) was noticed followed by a high mortality in higher Cd concentrations. Significant reduction in food consumption and growth rates was found at 32 μg l −1 and above Cd concentration. A significant relationship between Cd exposure and growth and feeding rates was noticed. The results obtained with these key aquatic organisms in the food chains complement those obtained with other aquatic organisms and gastropod snails. The findings of the present study and those of earlier studies suggested that Indian pond snail L. luteola are useful test organisms for ecotoxicology bioassays.