Robert Mann wrote:

> The Cornell experiments by Losey et al. showed monarch
> butterfly larvae severely poisoned by Bt corn pollen.

The Cornell study was not representative of actual field conditions.
Subsequent field studies to date has found Bt corn pollen does
not harm non-target butterfly larvae in real world field situations.

This is what the biotech industry expected since the concentration
of the crystalline endotoxin in Bt corn pollen is extremely low and
incapable of controlling even the target lepidopterans (e.g.the european corn
borer moth) For example, in Monsanto's Bt corn, (called MON 810)
1994 field data demonstrated expression levels of

0.18-0.39 ug/g in the kernal
7.93 -10.34 ug/g in the leaf
3.65-4.65 ug/g in the whole plant
0.09 ug/g in the pollen

These figures show the amount of toxin in the pollen is around 36-103
times less than what is present in the whole Bt corn plant and leaf tissues
(what the lep larvae must actually eat to be killed)

> Genetic modification (GM), also called genetic engineering (GE), is
> a topic to concern beekeepers.  If bees feed their larvae pollen containing
> -  to no good purpose  -  a modified version of a Bt toxin, then plant-GM
> might harm bees.  There are many other possible scenarios of harm to bees
> from GE plants.

It must be remembered Bt is nothing new - foliar sprays of Bt have
been used on row crops for decades. They have proven to be non-toxic
to non-lepidopteran insects such as honey bees (both larvae and adults).

The US Environmental Protection Agency has published a Fact Sheet
on Monsanto's Bt corn variety (event) which is called MON 810. Below
is what the fact sheet reports in regard to the toxicity of Bt protein
to honey bee larvae and adults (and other non-target insects):

"4. Impacts on Non-Target Organisms

a. Impacts on Non-Target Insect - Honey Bee (Larvae) B.t.k. HD-1
protein at 20 ppm is practically non-toxic to larval honey bees. An
LC50 was not possible to calculate since this was a single dose test.
Therefore, the NOEL is greater than 20 ppm."

b. Impacts on Non-Target Insect - Honey Bee (Adult)

There were no statistically significant differences among the various
treatment and control groups due to the sizable mortality that occurred
in all treatments. B.t.k. HD-1 protein at 20 ppm resulted in a mean
mortality of 16.2%. Because mortality was observed at the single dose
tested, a NOEL could not be determined from this study, but it was
less than 20 ppm. 20 ppm was determined to be significantly higher
than exposure conditions in the environment.

c. Impacts on Non-Target Insect - Parasitic Hymenopteran

B.t.k. HD-1 protein at 20 ppm is practically non-toxic to
Brachymeria intermedia. Since this is a single dose study,
 an LC50 cannot be calculated. The NOEL is greater than 20ppm.

d. Impacts on Non-target Insect - Green Lacewing Larvae

B.t.k. HD-1 protein at 16.7 ppm is practically non-toxic
 to green lacewing larvae after 7 days.
The NOEL is greater than 16.7 ppm.

e. Impacts on Nontarget Insect - Lady Beetles

B.t.k. HD-1 protein at 20 ppm is practically non-toxic
to lady beetles such as Hippodamia
convergens. The NOEL is greater than 20 ppm.

Paul Cherubini