COMPARATIVE ECOTOXICITY OF CADMIUM, CHLORPYRIFOS AND TRIPHENYLTIN HYDROXIDE FOR 4 CLONES OF THE PARTHENOGENETIC COLLEMBOLAN FOLSOMIA-CANDIDA IN AN ARTIFICIAL SOIL

1. Results of ecotoxicity tests on single species are often used for the evaluation of the environmental risk of substances. Because many tests are performed with parthenogenetic species, the question may arise, how reliable the results of these tests are when predicting the effects of a substance for both parthenogenetic and sexual species in the field. 2. In this investigation four clones of the species Folsomia candida were tested in a 35 day artificial soil test using cadmium (Cd), chlorpyrifos (CPF) and triphenyltin hydroxide (TPT-OH). 3. For Cd and TPT-OH no significant differences between clones were found, owing to a large variation within the clones. In the CPF experiment, differences between clones were small but significant. 4. Differences in the mode of action between the toxicants tested were found, these differences being the same for the different clones. 5. A new method was developed for analysis of triphenyltin and its degradation products diphenyltin and monophenyltin in Collembola. 6. No differences in uptake of Cd were found between clones. 7. The results support the conclusion that interclonal variation in sensitivity to soil toxicants in F. candida is not so large as to prohibit the use of this parthenogenetic species for soil ecotoxicity evaluations.