Our products are thoroughly and widely tested in comprehensive studies which go far beyond regulatory requirements which are in place relating to bees. In this context, the insecticide thiacloprid has a particularly advantageous environmental safety profile, in that it has a very low toxicity for bees.
Bees, unlike most insect pests which are controlled by the compound, can metabolize it very quickly and break it down using their enzyme system. This low toxicity to bees was confirmed by independent risk evaluation carried out by the German authorities who classified the products containing thiacloprid as the active ingredient as 'not dangerous to bees’.
This is demonstrated not only by extensive semi-field and field studies, but also through years of practical experience. As such, for example, thiacloprid has been applied for many years, to control destructive pests, to over a million hectares of winter oilseed rape whose nectar and pollen are one of the most important food sources for bee colonies in spring. Due to its safety for bees, the substance can even be applied during the flowering period. Despite this large-scale application over the years, the competent authority, the Julius Kühn-Institute, has not reported a single case in which a honey bee colony has been harmed by the application of thiacloprid.
If the product affected the sense of orientation of bees at concentrations relevant for use in the field, as suggested in some areas, this would have been seen in the field tests, as well as in practice by a continuous weakening of the colony by foragers not returning to the beehive; such effects have never been demonstrated.
The study by Professor Menzel is well known to us; they used a scientifically very interesting method for tracking the flight of bees. Unfortunately, however, all of the tested substances were administered in this study at concentrations that are much higher by far than the levels which bees may encounter normally in the environment. For example, the thiacloprid concentration which was used in his study was more than a hundred times greater than the highest exposure concentration for bees which was observed by independent scientists who carried out a German bee monitoring, large-scale long-term field study on bee health.
That such excessive test concentrations have effects is not surprising! This would be comparable to a scenario in which we are made to drink not two, but two hundred cups of coffee a day - again, the negative effects would easily be seen. As such, these effects have nothing to do with the realistic conditions which bees are exposed to in the field.
We, therefore, hold that our statement that thiacloprid is of low toxicity to bees is still justified. In our view, it is important that such agents which are particularly non-toxic to bees are made available, especially in the home and garden area. If such compounds were no longer available, older alternative products, which are often considerably more toxic to pollinators would have to be used instead – this would certainly make no sense for the protection of bees.