OECD 215: Fish Juvenile Growth Study

Protection of the fish community in freshwater is an important issue because fish play a major role in trophic cascades and as food resource for human beings. Therefore the impact on fishes of plant protection products, industrial chemicals, biocides and medicinal products that may get into aquatic environment has to be assessed.

Study Design

Test organisms

  • Oncorhynchus mykiss (rainbow trout)
  • Danio rerio (zebrafish)
  • Oryzias latipes (Japanese medaka)

Course of the test

The Fish Juvenile Growth study is designed to assess the effects of prolonged exposure to chemicals on the growth of juvenile fish.

Juvenile fish in exponential growth phase are placed, after being weighed, in test chambers and are exposed to a range of sublethal concentrations of the test substance dissolved in water preferably under flow-through or semi-static conditions for 28 days. Usually 5 concentrations in a geometric row and a control are tested. Results of an acute toxicity test, preferably performed with the species chosen for this test, should be available. The fish are fed daily, with a food ration based on initial fish weights. At the end of the test, the fish are weighed again.


During the test period the fish are observed daily for survival,  abnormal appearance and behaviour. Additionally, at the end of the test the weigth of all surviving fish is determined. The specific growth rate is calculated and the concentraion that would cause a x % variation in growth rate, i.e. ECx (e.g. EC10, EC20 or EC30) is analysed. The lowest observed effect concentration (LOEC) and the no observed effect concentration (NOEC) are estimated.

Guidelines and literature

  • OECD Guideline for Testing of Chemicals, No. 215: “Fish, Juvenile Growth Test“, adopted January 21, 2000