Boîte à outils pour l’homologation des pesticides

#622 Acute neurotoxicity (rat)

Objective of the study

The objective of the acute neurotoxicity study is to determine potential neurotoxicity of the active substance (major neurobehavioural and neuropathological effects) after single exposure.
More specifically, the neurotoxicity study, alone or in combination, provides information that can:
  • identify whether the nervous system is permanently or reversibly affected by the chemical tested;
  • contribute to the characterization of the nervous system alterations associated with exposure to the chemical, and to understanding the underlying mechanism.
  • determine dose-and time-response relationships in order to estimate a no-observed-adverse-effect level (which can be used to establish safety criteria for the chemical).
 

Circumstances under which the study is recommended to be required

The acute neurotoxicity study should always be conducted.
 

Test organism

The acute neurotoxicity study is conducted with the adult rat.
 

Test substance

Technical grade active ingredient
 

Typical endpoints of the study

Typical endpoints of the acute neurotoxicity study include (among others):
  • no-observed-adverse effect level;
  • toxic response data, including signs of toxicity or mortality;
  • description of neurobehavioural, neuropathological, and neurochemical or electrophysiological findings, if available.
As determined by the responsible authority, additional measurements may also be recommended, such as cholinesterase activity for certain pesticides, e.g. organophosphates and some carbamates. The route of exposure should correspond with the primary route of exposure.
 

Test guidelines

The following test guidelines may be used for the acute neurotoxicity study: