> in the article I just sent an url for the pollen 
> gathering bees take about seven days to accumulate 
> the same amount of ng of imidacloprid as nectar 
> gathers get in a day.  I realize that these are 
> theoretical figures, but the assumptions seem
> pretty reasonable to me.

I read that paper, and the assumptions seem utterly 
silly to me. The reasoning, too.

The apidologie.org link you provided was either
broken or sluggish, so here's a different link
to the same paper:

http://umweltbund.de/pdf/modes_of_honeybees.pdf

But the paper is utterly useless, as it contains 
nothing but guesses tied up in pretty bow to make 
them look more authoritative.  I'm really surprised
it made it to publication at all.

Here's how they estimate the different levels of 
consumption of nectar:

"Nectar foragers achieve 10 trips/ day on average, 
of about 30 to 80 min each... with a maximum of 
150 trips/ day... and pollen foragers achieve 10 
trips/day on average, of 10 minutes each..."

Say what?  Pollen foragers ALWAYS make shorter
trips than nectar foragers?  This faulty starting 
assumption is the sole reason for the higher figure 
for the foragers.

Its a guess, nothing more, and it is a very bad guess,
given than bees will always hedge their bets, foraging
for BOTH pollen and nectar from multiple sources at
all times, just in case the primary sources "dry up".
(I'll cite Seeley's book for this, but the observation
is noted everywhere by everyone.)

Further, they make basic and profound errors in their
assumptions of what food sources are available from
where at any one point in time, and assume that all 
nectar, all pollen, and all honey are equally 
contaminated with the same exact pesticide, thusly: 

"As we do not know the bees' differential consumption 
of nectar and honey we related their sugar consumption 
depending on whether they consume nectar or honey."

Translation - 'We guessed'.  
But the assumptions and poor reasoning gets worse...

"With the example of sunflower, when a honeybee 
requires 1 mg of sugar, it will have to consume 
either 2.5 mg of fresh sunflower nectar or 1.25 mg 
of sunflower honey."

But there is never going to be a hive that has both
100% of its nectar coming in from one source, nor
will 100% of its honey have been made from one source,
let alone the same source.

No beehive is going to forage on one crop alone.
It will fly miles away to forage on alternate sources,
just because bees like the hedge their bets.  So
there would be no hive where the only choice is
sunflower nectar.  Further, it takes some time to
make honey, so it is an absolute certainty that the
honey in the hive will be from a prior bloom, rather 
than the same crop being currently foraged.  This 
is basic beekeeping, and common knowledge.

Bottom line, this paper bent over backwards to
cherry pick a bunch of guesses and quotes from 
other peoples' papers to get the highest numbers 
possible.  It is not science, it is politics 
wearing an ill-fitting lab coat and trying to
look all pipe-smoking and professorial.

There are holes in this paper that any beekeeper 
can drive his truck through.  As such, this paper 
has value to beekeeping, but sadly, its only value 
is as smoker fuel.

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