EFSA identifies risks to bees from neonicotinoids

Scientists at the European Food Safety Authority (EFSA) have identified a number of risks posed to bees by three neonicotinoid insecticides.

The Authority was asked by the European Commission to assess the risks associated with the use of clothianidin, imidacloprid and thiamethoxam as seed treatment or as granules, with particular regard to: their acute and chronic effects on bee colony survival and development; their effects on bee larvae and bee behaviour; and the risks posed by sub-lethal doses of the three substances.

Where the risk assessments could be completed, EFSA concluded the following for all three substances:

Exposure from pollen and nectar. Only uses on crops not attractive to honey bees were considered acceptable.

Exposure from dust. A risk to honey bees was indicated or could not be excluded, with some exceptions, such as use on sugar beet and crops planted in glasshouses, and for the use of some granules.

Exposure from guttation. The only risk assessment that could be completed was for maize treated with thiamethoxam. In this case, field studies show an acute effect on honey bees exposed to the substance through guttation fluid.