I'm catching up with my reading on Bee-L.  I noticed that Jim brought up an old comment of mine in this thread.


I said:

"In nature???  Not likely, given that the displacement kinetics are completely unnatural.  Those metabolites aren't going to be found in a normal synapse, and there isn't anything else except ACh in there to compete with [Imidacloprid]."

What this means...please read carefully...is that there is nothing to displace imidacloprid in a bee's synapse.  It cannot be displaced by the native acetylcholine, and it isn't destroyed by acetylcholinesterase.  So to all intents and purposes, in "field relevant conditions" (not a test tube, not what Casida does) it is IRREVERSIBLE BINDING.  This is what is happening out there in the field to each bee that gets exposed....some of her synapses are bound to neonics IRREVERSIBLY (because there isn't anything that occurs naturally in that tiny synapse that can displace the neonic).

Does this matter?  Some studies say yes, others say no.  To the individual bee, it is devastating.  But the bee is part of a superorganism, and so that makes each bee relatively insignificant.  So insignificant, in fact, that many discount the overall lower numbers of bees in hives now as compared to pre-1970 as due to other factors, or as not making a difference to the overall performance of the colony.

I have an extensive bibliography on neonics that needs a meta-analysis.  It's slow work, and only Ghislain has offered to help me with it.  So far, I/we cannot present an overall conclusion because I/we am/are working at a snail's pace given other things going on, but I can say...yes, imidacloprid at sublethal levels affects bees significantly.  And I believe that sublethal effects of neonics in general reduces colony performance and subjects them to greater effects of other pathogens.

Christina


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