>Look at the bottom line too, Randy.

> This is another link:
>
> http://www.bbsrc.ac.uk/news/food-security/2013/130327-pr-pesticide-combinati
> on-affects-bees.aspx


Thanks Ghislain, but not only should one *look* at the bottom line, one
should also *read* it!  Two papers by the same authors with the same
results should not be called "two new studies," but rather *one* new study!

In any case, aha, I thought--someone had found something of interest!
 Sadly, I was disappointed.

Gavin noted correctly that "For me, this smacks of research divorced from
the reality of beekeeping, trying to tell us things that don't really
happen in reality - at least not to any great extent.  But please correct
me if I'm wrong."

Gavin, you are not wrong.  The study hinges on the applied dose, in which
the authors applied solutions of the neonics at ~2.5 ppb directly to
isolated brain cells in the lab.  They based these concentrations upon the
levels measured in nectar of treated crops, and cited Suchail (2004) as
justification that the neonics then translocated to the brain.

Unfortunately, the authors misinterpreted the graphs in Suchail's paper of
the actual distribution of imidacloprid in the bees' body over time!  Had
they interpreted correctly, they would have noticed that no more than 5% of
the dose of imidacloprid ever reached the bees' heads (and that was with
DMSO added as a membrane-penetrating solvent).  Suchail did not study the
other insecticides they tested, so the authors had no justification for the
doses applied of those products.

Bottom line, the authors' findings were based upon levels of imidacloprid
at least 20x higher than field-realistic exposure, and upon unsubstantiated
doses of coumaphos and clothianidin.  Had the authors actually fed the test
bees the pesticides, and then later measured the action potentials, we may
have actually learned something!

However, their summary was succinct:

"In summary, our findings show that imidacloprid, clothianidin and
coumaphos oxon are potent neuromodulators in the insect brain."

But we already knew that, since that is the well-established mode of action
of these insecticides!

Once again, I am disappointed by a poorly-designed study being hyped up by
the anti-neonic camp.

-- 
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com

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