OECD Guidelines for the Testing of Chemicals, Section 2
Effects on Biotic Systems
- 2074-5761 (online)
The OECD Guidelines for the Testing of Chemicals is a collection of about 150 of the most relevant internationally agreed testing methods used by government, industry and independent laboratories to identify and characterise potential hazards of chemicals. They are a set of tools for professionals, used primarily in regulatory safety testing and subsequent chemical and chemical product notification, chemical registration and in chemical evaluation. They can also be used for the selection and ranking of candidate chemicals during the development of new chemicals and products and in toxicology research. This group of tests covers effects on biotic systems.
Test No. 234: Fish Sexual Development Test
- 28 July 2011
- 9789264122369 (PDF)
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.