>Maybe, but the article of cedric alaux shows a reduction in the activity
of glucose oxidase (responsible for the sterilization of brood and food)
and synergy with the opportunistic parasite nosema.
Correct, but effects were not strong, nor did they include a positive
control such as typical plant allelochemicals in nectar and pollen for
reference. I'm certainly not suggesting that neonics don't suppress
immunity. What I'm saying is that the authors shouldn't have included
irrelevant studies.
>
> >Randy, don't you confuse a dose and a concentration?
> Giving 200mg to 1 kg of rat is in fact giving 1-20ng to a bee (100mg) and
> if you look at the LD50 20ng/bee we have 90% mortality ... it is in the
> correct range of study
>
Thanks for pointing this out Ghislain. One of us is way off on our math.
Readers, please help us out!
By my math, 1 ppb = 1 part per billion = 1 ėg/kg = 1 ng/g
Since a bee weighs 1/10th gram, then a concentration of 1ppb = 0.1ng/g
So let's look at the rat dose of 200mg/kg = 200ppm = 200,000ppb
So a bee at 200mg/kg would be equivalent to 20,000ng/g.
Someone mathematically inclined please check our math and let us know which
calculation (Ghislain's or mine) was correct!
However, bees are far more sensitive to neonics than are mammals. The dose
given to the rat was about 1/5th the LD50 for rats. However, it is
difficult to compare the effect on immune response, since toxicity is due
to agonistic effects, whereas immune adverse effects are likely due to
antagonistic effects.
>
> >hmmmm, should we really read again the studies on chronic toxicity?
>
Apparently yes.
>don't forget that pesticides fields are mixed with substances that block
> detoxification with the effect that 1 +1 = 10
As far as I know, only one class of fungicides has been found to synergize
with neonics, so not sure of your point.
Ghislain, I'm not arguing that neonics may have effects on animal immune
systems. But this is a honey bee discussion group. I have looked hard at
data suggestive of bee immune suppression by neonics. This paper adds
nothing data wise to that discussion.
--
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com
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