Bill T> In essence, they found a pathway (the way the pesticide works) to make the
nics less harmful to bees and bumblebees. Good news for bumblebees.


The way I read this study is that the bees' P450 enzyme CYP9Q3 is helping to detox thiacloprid but is not as effective against imidacloprid. Also, there was a side note that some of the common fungicides, currently in use, inhibit CYP9Q3 which in the real world works against a bee's immune system. Bayer sponsored the study which I think adds some bias. One possibility is that Bayer is looking for a way to preserve the use of imidacloprid by trying to find out how CYP9Q3 works to detox thiacloprid, and also to point out that spraying fungicides are partly to blame for the toxicity of their products.  On the other hand, it's good work and it brings some awareness to the synergistic effects of some fungicides.  It's good news that bumble bees have a similar enzyme (CYP9Q4) and it may be that they are not as likely to be exposed to as many fungicides. 


>"Honeybees are more than 1,000 times less sensitive to the neonicotinoid thiacloprid than imidacloprid, with the latter classified as 'highly toxic' but the former categorized as only 'slightly toxic' or 'practically non-toxic' according to the official categories of the US Environmental Protection Agency,"

>Studies conducted in cells in the lab suggested a link between differences in the honeybees' sensitivity and the function of a particular P450 enzyme called CYP9Q3. To provide additional evidence that CYP9Q3 is the primary honeybee P450 that confers tolerance to thiacloprid, the researchers engineered fruit flies to express various P450 enzymes from the honeybees and then tested their sensitivity to the pesticides. The studies confirmed that CYP9Q3 is the key enzyme. The researchers also found that bumble bees have a closely related P450 enzyme called CYP9Q4, which explains similar differences in their pesticide sensitivities.

Bill Hesbach
Cheshire CT

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