Abstract

The German Biologische Bundesanstalt (BBA) and RIVM have developed test methods for determining sublethal effects of chemical substances on earthworms. The BBA-method is especially designed for testing pesticides while the RIVM-method is applicable on "all" types of chemicals. After a second ring test, wich showed a considerable variation in results, the BBA method was revised. To compare both methods, the substances parathion and benomyl were tested using the BBA-method and the RIVM-method. In the BBA-method the test substances are sprayed over the soil surface, while they are mixed homogeneously through the soil in the RIVM-method. In order to enable comparison of the results of both test methods, dosages used in the BBA-method were recalculated to concentrations in soil using the equation: kg/ha * 5.3 = mg/kg dry soil. In case of parathion, the BBA-method was more sensitive than the RIVM-method with respect to juveniles/worm/week and number of juveniles/ fertile cocoon. NOEC-values for these parameters, which appeared to be most sensitive in both methods, were about a factor of 10 lower in the BBA method compared to the RIVM-method. It cannot be assessed which method was most sensitive for cocoon production, growth and fertility of the cocoons. In case of benomyl, the RIVM-method was more sensitive than the BBA-method with respect to fertility of the cocoons and the number of juveniles/fertile cocoon. For cocoon production and juveniles/ worm/week the BBA-method was more sensitive. It cannot be assessed which method is most sensitive for growth. For benomyl the final NOEC-values for the most sensitive parameter appeared to be almost similar in both test methods.