Title: Test No. 222
Description: This Test Guideline is designed to be used for assessing the effects of chemicals in soil on the reproductive output (and other sub-lethal end points) of the earthworm species Eisenia fetida or Eisenia andrei. Adult worms are exposed to a range of concentrations of the test substance either mixed into the soil or applied to the soil surface. The range of test concentrations is selected to encompass those likely to cause both sub-lethal and lethal effects over a period of eight weeks. The limit test corresponds to one dose level of 1000 mg/kg. This study includes the observation of unusual behaviour and morphology, the counting and weighing of the adult worms after the four primary weeks, the number of juveniles hatched at the end of the second 4-week period. The reproductive output of the worms exposed to the test substance is compared to that of the control(s) in order to determine the no observed effect concentration (NOEC) and/or ECx by using a regression model to estimate the concentration that would cause a x % reduction in reproductive output. The test concentrations should bracket the ECx so that the ECx then comes from interpolation rather than extrapolation.
Subjects: Ecology, Euthenics, Nature and nurture, Adaptation (Biology)