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

Juvenile Helix aspersa (1 month, Ig) 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 mu g.g(-1) (EC(50) = 1200 mu g.g(-1)), whereas zinc had a toxic effect from 4000 mu g.g(-1) (EC(50) = 5500 mu g.g(-1)) on. Lead, a nonessential metal, had no negative effect on growth, unlike cadmium (EC(50) = 140 mu g.g(-1)), as reported previously. Pentachlorophenol inhibited growth at a concentration of 500 mu g.g(-1) from the fourth week and 1000 mu g.g(-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. (C) 2000 Academic Press.