OECD 305: Bioaccumulation in Fish: Aqueous and Dietary Exposure

(GLP and non-GLP)

Degradation and accumulation studies are required for the Registration of Chemicals, Biocides, Detergents, Pharmaceuticals, Veterinary Medicinal Products and Agrochemicals, if the relevant substances have special properties and usages. Substances with e.g. high dissipation times and/or a lipophilic character reaching soil or water ecosystems need to be assessed for their degradation and accumulation potential.

Analytical Methods with 14C Radio-Labelled Substances

For these studies the use of radio-labelled test substances is recommended as they allow the detection of them and their metabolites to very low detection limits. This gives also the possibility to evaluate the transformation pathways for the environmental degradation of a substance. Additionally using 14C-labelled material, the various mineralisation rates of test substances can be measured by trapping evolved 14CO2 and a mass balance, including the formation of bound residues, can be established.

IBACON’s 14C-laboratory is provided with professional equipment up to the latest standards (scintillation counter, HPLC radio detection system, LC-MS/MS systems).

liquid scintillation counter and HPLC with radiodetection

OECD 305: Bioaccumulation in Fish, Aqueous and Dietary Exposure

The bioconcentration potential of substances in fish is examined preferably under flow-through conditions. The study consists of two phases: the uptake phase and the depuration phase. During the uptake phase, groups of fish are exposed to a minimum of two concentrations of the test substance and a control (or only one concentration of the test substance and a control when it is likely that the bioconcentration factor (BCF) is independent of the test concentration).

The uptake phase terminates when the concentration of the substance in fish reaches a steady state or after 60 days duration. If a significant uptake occurred, the fish are transferred in test substance free medium for the depuration phase.

The total radioactive residue in water and fish samples taken at specified time interval is measured. Based on the test substance concentration in the total wet weight of the fish and the concentration in water, the bioconcentration factor (BCF) or kinetic bioconcentration factor (BCFk) is calculated.

IBACON performs bioaccumulation studies on fish with the following species:

Danio rerio   Zebra-fish
Poecilia reticulata   Guppy
Cyprinus carpio   Common Carp
Oryzias latipes   Japanese Medaka
Pimephales promelas   Fathead Minnow
Lepomis macrochirus   Bluegill

Available Guidelines

  • Commission Directive 98/73/EC, Method C.13, Bioconcentration: Flow-Through Fish Test (EEC Publication No. L 305, 1998).
  • OECD Guideline for Testing of Chemicals No. 305: "Bioaccumulation in Fish: Aqueous and Dietary Exposure", adopted 2 October 2012
  • EPA Ecological Effects Test Guideline OPPTS 850.1730 Fish BCF, April 1996.
OECD 305: Uptake and depuration phase for bioaccumulation study in fish
OECD 305: Exposure and depuration phase for bioaccumulation study in fish
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