Acute Toxicity of Mercury, Copper and Zinc to a Freshwater Pulmonate Snail, Lymnaea luteola (LAMARCK)

The short‐term toxicity of mercury, copper and zinc was studied using a freshwater pulmonate snail, Lymnaea luteola (L AMARCK ). The median period of survival increases with decreasing the toxicant concentration. The 96 h LC 50 values and their confidence limits were 0.135 (0.112 … 0.186) ppm of Hg 2+ ; 0.172 (0.118 … 0.355) ppm of Cu 2+ ; and 6.13 (5.73 to 7.19) ppm of Zn 2+ . The relative potency ratio indicates that the Hg 2+ ions were most toxic, followed by Cu 2+ and Zn 2+ ions.