Bob Harrison wrote:

" Researchers are puzzled that the 1ppb of imidacloprid detected in nectar &
pollen could be the root of the problem. After all ppb of known higher toxic
chemicals have been found and the bees *seemed* unaffected."

The amounts found last summer in canola following treated potatoes were above
1 ppb.  In wax it was 2 ppb which disturbs me.  It also exceeded 2 ppb in honey
and pollen in some samples.  If the smoking gun you are looking for is dead bees
at the entrance of a deadout I do not think you will find this with imidacloprid.
I always am reminded of Bayer's own words when marketing imidacloprid as an ant
and termite treatment:  imidacloprid kills the colonies by weakening them and
making them more susceptible to disease (slightly paraphrased to avoid me having
to find the exact quote, which is very close).

Also from Bob:

 "What is the problem if the problem is *not* being caused by imidacloprid"

Bayer has now funded about a million Canadian dollars worth of study here and I
am sure it would like to have found something to point to as the "problem".  The
syndrome has been documented,  and I do not think that I have any mental blocks
against accepting another cause or group of causes, but nothing has been proposed
so far that seems plausible to me.

Chris Slade wrote that viruses could be a cause of disappearing bees.  I would like
him to know that virus testing was part of the research and did not turn up anything
there.  

I would like to mention that I have been told that the researchers would like to follow
some of my hives this year as they move from wintering yards to blueberries to canola
and if you have ideas for how to scientifically find "the smoking gun", then post them.
My own thought is some test to determine which comes first, the diseased brood or
the disappearance of adult bees.

 Hervé Logé wrote:
" I was under the feeling pesticides intoxication is one more trouble bees have to 
face...."     
and
".... Or that bees could have passed through the winter if
not exposed but exposure was too much for half of them."
Both these paragraphs were very well expressed.

I would add to his comments on pesticide acceptability for society that a
pesticide with a half life of over a year cannot in my opinion be deemed
acceptable.  The testing here has always confirmed high residues in the soil
and now shown that these residues are expressed in the succeeding crop
years.   The French found amounts in untreated sunflowers following treated
sunflowers similar to those in treatment years in some cases, and the amounts
found in New Brunswick in untreated canola following potatoes are similar to what 
Cynthia Scott-Dupree found in canola treated with imidacloprid in Ontario.

 "But I think bio-essays (i.e. proboscis extension
response) to evaluate sublethal effects (that can lead
to medium term disorder in the colony, or weakness
that will make wintering a hazardous venture) are very
recent (Pham-Delègue, 2002). "

Thankyou for the reference for this Herve.  If it would be possible for you to
summarize the results of this paper, it would be much appreciated by me, and
perhaps others who do not have access to apidologie, or have limited French.
Bayer is very dismissive of some research regarding sublethal effects, but it
is difficult for them to completely dismiss the research by Madame Pham-
Delegue, because they have published pictures of her proboscis extension 
testing in their booklet on imidacloprid and bees and obvious consider her 
credible.

Finally, I would like to make an observation after being involved with
studies on imidacloprid and bees for a few years now.  One problem that I
see is the huge cost involved in every sample (it is about three or four hundred
dollars per sample).   With government cutbacks and user pay philosophy it 
makes it almost impossible to have research independent of Bayer funding.
It should be possible to determine the ppb in a sample by using an appropriate
short life span test insect instead of mass spectrometers and liquid chromatographs.
So, for example, if you added known amounts of imidacloprid to diluted honey
until you found the LD 50 (lethal dose for 50%) for fruit fly flies kept on that honey
for two days, then why not use fruit flies to test honey samples after that.  Or,
maybe larder beetles could be used for pollen samples.  Then, if you get samples
that produce a killing dose you could measure the dilution possible to maintain 
the killing dose and extrapolate the ppb.  In order to produce the most accurate
result, the most highly sensitive organism should be chosen.  I believe that some
marine larvae like shrimp and lobsters are very sensitive, but they don't eat honey
or pollen.  Perhaps there is a winning science fair project for some young persons there!

Regards
Stan

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