Test No. 202: Daphnia sp. Acute Immobilisation Test

Introduction

“OECD 202” actually refers to the Daphnia sp. Acute Immobilisation Test, a standard laboratory procedure used to assess the short-term toxicity of chemicals to freshwater invertebrates like Daphnia.

Here's what you need to know about OECD 202:

What it does:

  • Measures the acute (short-term) effects of a substance on the swimming ability of Daphnia.
  • Young Daphnia (less than 24 hours old) are exposed to different concentrations of the test substance for 48 hours.
  • The number of immobilized Daphnia at 24 and 48 hours is compared to a control group.
  • The results are used to calculate the EC50 (effective concentration at which 50% of the Daphnia are immobilized).
Test No. 202: Daphnia sp. Acute Immobilisation Test

Applications:

  • Used to assess the environmental hazard of chemicals and products.
  • Required for regulatory purposes in many countries.
  • Important for understanding the potential impact of chemicals on freshwater ecosystems.

Key features:

  • Relatively simple and inexpensive test.
  • Standardized protocol ensures consistency and reproducibility of results.
  • Can be modified to study specific chemicals or environmental conditions.