Test No. 251: Rapid Androgen Disruption Activity Reporter (RADAR) assay

The Rapid Androgen Disruption Activity Reporter (RADAR) Test Guideline describes an aquatic assay that utilizes transgenic Oryzias latipes (O. latipes, Japanese medaka) eleutheroembryos at day post hatch zero, in a multi-well format to detect chemicals active on the androgen axis. The RADAR assay was designed as a screening tool to provide a short-term assay to measure the response of eleutheroembryos to chemicals potentially active on the androgen axis. Test organisms are exposed for 72 hours in six-well plates in the presence and absence of a co-treatment with 17-methyl testosterone. The assay comprises five concentrations of the test chemical. At the end of the exposure, fluorescence imaging is measured and transformed into a numerical format; the statistical analysis and data interpretation procdure enable to determine whether the test chemical is considered active or not active.