Standardized growth toxicity testing (Cu, Zn, Pb, and pentachlorophenol) with Helix aspersa.

Juvenile Helix aspersa (1 month, 1 g) were exposed for 4 weeks to food contaminated with copper, zinc, lead, and pentachlorophenol. At concentrations observed in contaminated soils, two essential metals at low levels (Cu and Zn) had a dose-dependent sublethal action on growth. Copper inhibited growth dose-dependently between 1000 and 2000 microg small middle dotg(-1) (EC(50)=1200 microg small middle dotg(-1)), whereas zinc had a toxic effect from 4000 microg small middle dotg(-1) (EC(50)=5500 microg small middle dotg(-1)) on. Lead, a nonessential metal, had no negative effect on growth, unlike cadmium (EC(50)=140 microg small middle dotg(-1)), as reported previously. Pentachlorophenol inhibited growth at a concentration of 500 microg small middle dotg(-1) from the fourth week and 1000 microg small middle dotg(-1) from the first week on. The results obtained with these key organisms in the food chain (consumers) complement those obtained with other land invertebrates (earthworms, springtails, wood-lice, etc.). The findings of the present study and those of earlier studies indicate that juvenile snails are useful organisms for testing the sublethal toxicity of chemicals acting via the food, i.e., the main route of toxicant uptake in land animals. Copyright 2000 Academic Press.