Objective of the study

This study is conducted to determine the effects of a pesticide on honeybee development and brood activity, and should provide sufficient information to evaluate its possible risk to honeybee larvae. The results of this test can also be used to define the need for further evaluation, in particular in a step-wise procedure for evaluating the risks of pesticides to bees, based on sequential progression from laboratory toxicity tests to semi-field and field experiments.

Circumstances under which the study is recommended to be required

Recommended to be carried out for substances for which sub-lethal effects on growth or development cannot be excluded, unless it can be justified that honeybee brood would not be exposed to the pesticide. This study may not be required in situations where bees are not likely to be exposed, including (but not limited to): food storage in enclosed spaces; soil applications with non-systemic pesticides (except granules, which may release dust if drilled); non-systemic dipping treatments for transplanted crops and bulbs, non-systemic rodenticidal baits; use in greenhouses without bees as pollinators.

Test organism

The study is conducted with honeybee larvae (Apis mellifera).

Test substance

• Technical grade active ingredient
• A study with the end-use product is recommended to be required if: o the pesticide product contains more than one active substance; or o the toxicity of the pesticide product cannot be reliably predicted on the basis of the active ingredient alone.

Typical endpoints of the study

• Mortality: 72h-LD50 (μg a.i. / larvae)
• other observations, including the presence of uneaten food at test termination.

Test guidelines

The following test guidelines may be used for determination of bee brood toxicity:

• OECD Guidelines for the Testing of Chemicals. Test No. 237: Honey bee (Apis mellifera) larval toxicity test, single exposure.
• COLOSS BEEBOOK Vol I: Standard methods for toxicology research in Apis mellifera.