# Commission Directive 2004/73/EC of 29 April 2004 adapting to technical progress for the twenty-ninth time Council Directive 67/548/EEC on the approximation of the laws, regulations and administrative provisions relating to the classification, packaging and labelling of dangerous substances (Text with EEA relevance), Division 1.3: PRINCIPLE OF THE TEST METHOD

Extent: E+W+S+N.I.

The test chemical is administered by the oral route across a range of doses to several groups of laboratory rodents. Repeated doses are normally required, and the dosing regimen may be 28 days, subchronic (90 days) or chronic (1 year or longer). The procedures set out in this Test Method may also be used for an acute neurotoxicity study. The animals are tested to allow the detection or the characterization of behavioural and/or neurological abnormalities. A range of behaviours that could be affected by neurotoxicants is assessed during each observation period. At the end of the test, a subset of animals of each sex from each group are perfused in situ and sections of the brain, spinal cord, and peripheral nerves are prepared and examined.
When the study is conducted as a stand-alone study to screen for neurotoxicity or to characterize neurotoxic effects, the animals in each group not used for perfusion and subsequent histopathology (see Table 1) can be used for specific neurobehavioural, neuropathological, neurochemical or electrophysiological procedures that may supplement the data obtained from the standard examinations required by this Method (1). These supplemental procedures can be particularly useful when empirical observations or anticipated effects indicate a specific type or target of a chemical's neurotoxicity. Alternatively, the remaining animals can be used for evaluations such as those called for in Test Methods for repeated dose toxicity studies in rodents.
When the procedures of this Test Method are combined with those of other Test Methods, a sufficient number of animals is needed to satisfy the requirements for the observations of both studies.

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Source: https://www.legislation.gov.uk/eudr/2004/73/annex/2H/division/B.43/division/1/division/1.3 (the official version)
Page: https://openlegislation.uk/eu-directive-2004-73/annex-2H/division-B.43/division-1/division-1.3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.