>
> >Goulson dismissed as "nonsense" Julian Little's suggestion that the doses
> given to the bees were higher than in reality.


This was a legitimate criticism, so I reviewed the details of the study.
 The authors used two dosages: 24 ppb and 241 ppb.

Reality check is that typical measured doses in nectar are rarely over 4
ppb, and typically much lower.  At 1 ppb, it appears that the effects upon
a bee are similar to those upon a human after drinking a cup of coffee.
 You can extrapolate the effect of drinking 24 cups!

I'd have to agree with the Bayer rep (whom I've never heard of before) when
he says that the doses were unrealistic.  Especially the 241 ppb dose,
since anything above 50 ppb is generally considered to be acutely toxic.

Anther consideration is how the researchers actually prepared the
solutions.  They did not mention which solvent they used to dissolve the
original pure imidacloprid.  I've written them for details.

One thing that I find troubling about these studies on the neonicotinoids
is that there is no standardization of the doses used to test for adverse
effects.  To their credit, in the recent "Harvard" study, the authors began
the trial with an appropriate and field-realistic range of dosages--0.1,
1.1, 5.3, and 10.5 ppb (it was not until later that they decided to ramp up
the doses to unrealistic levels).

I would suggest such a range to be standard for studies in the future (0.1,
1.0, 5, and 10 ppb).

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

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html

Guidelines for posting to BEE-L can be found at:
http://honeybeeworld.com/bee-l/guidelines.htm