This guidance document was originally published in 2012 and updated in 2018 to reflect
new and updated OECD test guidelines, as well as reflect on scientific advances in
the use of test methods and assessment of the endocrine activity of chemicals. The
document is intended to provide guidance for evaluating chemical using standardised
test guidelines. Specific objectives include providing a description of the OECD conceptual
framework for evaluating chemicals for endocrine disruption, background on the standardised
test methods used, and guidance for interpreting the outcome of individual tests.
The general approach taken by the document is primarily to provide guidance on how
test results might be interpreted based on the outcome of standardised assays. Key
questions addressed in the document concern likely mechanisms of endocrine action
and any resulting apical effects that can be attributed to such action. The document
is not proscriptive but provides suggestions for possible next steps in testing (if
any) which might be appropriate for a regulatory authority to take, given the various
data scenarios. The guidance document is focused primarily on endocrine modalities
included in the conceptual framework; estrogen, androgen, and thyroid mediated endocrine
disruption and chemicals that interfer with steroidogenesis.