INFLUENCE OF CADMIUM, COPPER, AND PENTACHLOROPHENOL ON GROWTH AND SEXUAL DEVELOPMENT OF EISENIA-ANDREI (OLIGOCHAETA, ANNELIDA)

In the existing guidelines for earthworm toxicity testing, mortality is the only test criterion. Mortality is, however, not a very sensitive parameter, and from an ecological point of view growth and reproduction are more important for a proper risk assessment of chemicals in soil. In this study the growth and sexual development of juvenile earthworms were considered as test criteria in a standardized earthworm toxicity test. The effect of Cd, Cu, and pentachlorophenol on the growth and sexual development of juveniles of the species Eisenia andrei was studied in an artificial soil substrate. Two tests with Cd were carried out to study the effects of the mode of application of the food source (cow dung). EC50 (50% effective concentration) values for the effect of Cd, Cu and pentachlorophenol on the growth of E. andrei were 33 -96, > 100, and > 32 mg kg-1 dry soil, respectively, and there was no observed effect at 18-32, 56, and greater-than-or-equal-to 32 mg kg-1 dry soil, respectively. Sexual development of the earthworms was inhibited at 10 mg Cd kg-1 and 100 mg Cu kg-1 dry soil, but was not affected at the highest pentachlorophenol concentration tested (32 mg kg-1 dry soil). The results were the same whether the food was applied in a hole in the middle of the soil or mixed homogeneously through the soil.