October 8, 1999
The insecticidal seed dressing Gaucho® (active ingredient: imidacloprid) is also used in
crops which are relevant for honeybees. The seed dressing protects these crop plants
against soil and foliage dwelling pests. Shortly after Gaucho has been launched on the
market, a novel bee malady occurred in France. Due to this temporal coincidence some
confounded beekeepers postulated a causal relationship between the product Gaucho and the
novel bee symptoms.
In response to these speculations, further field studies were conducted in 1995 und 1997
to
examine potential effects of Gaucho on honeybees. These controlled experiments gave no
support for the assumed relationsships. The findings of these experiments were again
re-considered in 1998 during an extensive research project on behalf of the French
Ministry of Agriculture. Again, no effects were seen on honeybees under field relevant
exposure conditions. Supplemental investigations aimed to consider other causative factors
were conducted to only a very limited extent.
A couple of factors, solitarily or in combination, can evoke symptoms which very much
resemble those reported by the confounded professional beekeepers. Examples of such
factors are malnutrition, parasites, diseases, toxicants, unfavourable weather conditions,
genetic deficiencies and bee colony management (e.g. disease control measures). In
particular, spiroplasms and Varroa mites (frequently in combination with paralysis
viruses) cause nearly identical symptoms.Company
news release
N2265 |
