Division Circumstances in which requiredF1

A chronic toxicity study must be carried out unless it can be justified that continued or repeated exposure of fish is unlikely to occur or unless a suitable microcosm or mesocosm study is available.

Expert judgment is required to decide which test has to be performed. In particular for active substance for which there are indications of particular concerns (related to the toxicity of the active substance for fish or the potential exposure) the applicant shall seek the agreement of the competent authorities on the type of test to be performed.

A fish early life stage toxicity test might be appropriate where bioconcentration factors (BCF) are between 100 and 1 000 or where EC₅₀ of the active substance <  0,1 mg/l.

A fish life cycle test might be appropriate in cases where:

• the bioconcentration factor is greater than 1 000 and the elimination of the active substance during a depuration phase of 14 days is lower than 95 %, or

• the substance is stable in water or sediment (DT₉₀ > 100 days).

It is not necessary to perform a chronic toxicity test on juvenile fish when a fish early life stage toxicity test or a fish life cycle test has been performed; it is likewise not necessary to perform a fish early life stage toxicity test when a fish life cycle test has been performed.