OECD 202: Daphnia Sp., Immobilization Test

OECD 202 is an acute immobilization toxicology test that determines the concentrations of a material that immobilizes Daphnia species.

Standard testing for OECD 202 is performed by exposing young daphnids to the test substance at a range of concentrations for a period of 48 hours. Immobilization is recorded at 24 hours and 48 hours and compared with control values.

The results of OECD 202 are analyzed and the EC50 of 48 hours can be calculated. The method does not require EC50 at 24h, but it is optional and can provide additional information on the toxicity of the test sample to Daphnia species.

With the OECD 202 test method, a “Limit Test” can be performed at 100 mg/l of test substance or up to its limit of solubility in the test medium (whichever is the lower) to demonstrate that the EC50 is greater than this concentration.

Additional Testing Options

For Chronic Toxicity testing, OECD 211; Daphnia Magna Reproduction Test is commonly requested.

In additional to toxicology testing, customers request biodegradability and bioaccumulation testing to conduct a comprehensive Ecological Effects and Environmental Fate study.

For toxicology testing, it is beneficial to have data on the different performance, and physical and chemical properties of the material including structural formula, purity of the substance, stability in water and light, the Partition Coefficient* and results of a test for ready biodegradability*.

Regulatory & Branding Information

EPA Registration for Pesticides and Toxic substances generally requires data submitted for Series 850: Ecological Effects, Group A: Aquatic and Sediment-dwelling Fauna and Aquatic Microorganisms. Acute toxicity of freshwater invertebrates testing is required for any product which meets any of the following conditions:

  • End-use Products (EP) and Typical End-use Products (TEP) that are introduced directly into an aquatic environment
  • Products with the maximum expected environmental concentration (MEEC) or the estimated environmental concentration (EEC) in the aquatic environment that is greater than or equal to one-half the LC50 or EC50 of the TGAI when the EP is used as directed
  • Products with ingredients in the end-use formulation other than the active ingredient that is expected to enhance the toxicity of the active ingredient or to cause toxicity to aquatic organisms

OPPTS Guideline 850.1010 is an EPA guideline that tests against freshwater daphnids and is commonly requested for Aquatic Invertebrate Acute Toxicity testing.

Toxicology testing is commonly performed in order to support environmentally acceptable product label claims. Many products including lubricants, oil, personal care products, and detergents gain acceptance and a competitive edge in the market by determining low toxicological effects to biota. Customers commonly request OECD 202 as part of the toxicity component of the EU Ecolabel requirements for different product types including Lubricants.  Other toxicity tests commonly utilized to fulfill requirements for different EU Eco Labels include OECD 201; Algae Growth Inhibition Test and OECD 203; Fish, Acute Toxicity Test.

For any testing done to meet regulatory or third party labeling requirements, it is strongly recommended to review requirements prior to testing with the appropriate agency to determine which tests should be performed for label claims or regulatory acceptance.

* Please inquire with the lab to set up a GLP Toxicology Study

*OECD 117: Partition Coefficient (n-octanol/water), HPLC Method

*OECD 301: Ready Biodegradability

For more information on Toxicology Testing, contact our Environmental Testing laboratory at 847-483-9950 or info@situtest.com.