Kit de Herramientas para el Registro de Plaguicidas

#901 Route and rate of degradation in soil – aerobic and anaerobic soil metabolism

Objective of the study

This study is designed for evaluating aerobic and anaerobic transformation of pesticides in soil.
Specific soil types are exposed to the highest application rate of the test substance mixed into the soil. The study is usually conducted less than 120 days.

 

Circumstances under which the study is recommended to be required

Aerobic transformation: data with the active ingredient are recommended for all terrestrial outdoor and greenhouse uses.

Anaerobic transformation: data with the active ingredient are recommended for all terrestrial outdoor and greenhouse uses unless it can be shown that anaerobic conditions are unlikely to occur for intended uses.

 

Test organism or substrate

  • Soils representing a range of relevant soils to vary in their organic carbon content, pH, clay content and microbial biomass
  • Aerobic and anaerobic studies with one soil type are generally sufficient for the evaluation of transformation pathways
  • Rates of transformation should be determined in at least three additional soils
  • The types of soils tested should be representative of the environmental conditions where use or release will occur

Test substance

  • Technical grade active ingredient
  • A study with the end-use product is recommended as an appropriate alternative for poorly soluble active ingredients
  • Non-labelled or labelled test substance can be used to measure the rate of transformation.
  • Labelled material is required for studying the pathway of transformation and for establishing a  mass balance


Typical endpoints of the study

  • Half-life or DT50, DT75 and DT90 for the test substance and, where appropriate, for major transformation products including confidence
  • Proposed pathways of transformation, where appropriate;

Testing guidelines

The following test guidelines may be used for determination of the reproductive toxicity: