Test No. 234: Fish Sexual Development Test
This Test Guideline describes an assay that assesses early life-stage effects and
potential adverse consequences of putative endocrine disrupting chemicals (e.g. oestrogens,
androgens and steroidogenesis inhibitors) on fish sexual development. In the test,
fish are exposed, from newly fertilized egg until the completion of sexual differentiation
at about 60 days post hatch, to at least three concentrations of the test substance
dissolved in water. In each treatment level and control(s) group(s), a minimum of
four replicates is recommended. At termination of the test, two core endpoints are
measured in each fish: vitellogenin concentration from head and tail or from blood
sampling, and proportion of males, females, intersex and undifferentiated fish through
gonadal histology. In fish species possessing a genetic sex marker, the genetic sex
is identified to determine sex reversal in individual fish. The combination of the
two core endocrine endpoints, vitellogenin concentration and phenotypic (and possibly
genotypic) sex ratio, enable the test to indicate the mode of action of the test chemical.
Published on July 28, 2011Also available in: French
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