OECD 236: Fish Embryo Acute Toxicity Test

The fish embryo acute toxicity test  is a candidate to replace the fish acute toxicity test. For whole effluent testing this is already performed in Germany. The nervous system of fish embryos is not well-developped and therefore it is assumed, that fish embryo do not perceive pain as adult fish. The OECD guideline for the testing of chemicals was adopted in July 2013 and since 2014 we perform this test at ibacon.


Study Design

Test Organisms

  • Danio rerio (zebrafish)

Course of the test

Newly fertilised zebrafish eggs are exposed to the test item for 96 hours. Every 24 hours the fish embryos are assessed for coagulation, lack of somite formation, lack of detachment of the tail-bud from the yolk sac and lack of heartbeat. If one of these symptoms occur, the embryo is recorded as dead. Based on the observations the LC50 is calculated.

More information is coming soon.

Guidelines and literature

  • OECD Guideline for Testing of Chemicals, No. 236: “Fish Embryo Acute Toxicity (FET) Test“, adopted July 26, 2013