The acute toxicity of test substances to adult earthworms (Eisenia fetida) in a defined soil medium is tested.
Various amounts of the test substance are added to an artificial soil (10% peat, 20% kaolin clay, 70% fine sand, adjusted by calcium carbonate to pH 5.5 - 6.5). Subsequently, e.g. 10 animals per concentration (including controls) are used with four replicates. After an exposure time of 7 and 14 days at 20°C, the surviving animals are counted. As test result, the concentration is calculated, at which mortality is 50% (LC50 in mg/kg soil). In addition, the highest tested concentration is given, at which no lethal effects are observed (NOEC, no observed effect concentration).
As a further development of the acute toxicity tests, the "Earthworm avoidance test" in the sub-lethal concentration range according to ISO 17512-1 is to be mentioned. Here, the avoidance/escape behavior of earthworms is used as an endpoint. A method for determining the reproductive toxicity of earthworms is described in ISO 11268-2 and OECD 222.
Test substance properties
The test procedure is not applicable for volatile substances. The possible degradation of the test substance is not considered in this test design.
In the Hydrotox laboratory currently no terrestrial ecotoxicity tests are conducted under GLP, but co-operation laboratories are commissioned with these tasks.