[permaculture] GM crops effect on honey bees : some effect or no effect

Lawrence F. London, Jr. lfl at intrex.net
Thu Apr 12 13:17:06 EDT 2007


-------- Original Message --------
Subject: [SANET-MG] GM crops effect on honey bees : some effect or no effect
Date: Thu, 12 Apr 2007 08:59:20 -0400
From: jcummins <jcummins at UWO.CA>
To: SANET-MG at LISTS.IFAS.UFL.EDU

AgBioWorld recently put out some testimony in a Congressional Committee
claiming that there was no effect of Bt crops or bacteria on honey bee.
I am reminded of my discussion with the editor of the British Food
Journal over an article on GM sweet corn which I thought should be
removed because their was evidence of fraudulent methods in opinion
gathering. His reply, published in the journal  proclaimed that "There
is a common misconception that science is about facts"Alas, that seems
to be the guiding principle of peer review in biotechnology.
However, the evidence on GM crops and bees needs much more independent
investigation. Nevertheless, the evidence on pesticides is clear and
convincing.. The pr game has been , I believe, to focus away from the
pesticide evidence to protect the corporations from liability. I keep
trying to remind people that pesticides are clear threats while GM is a
part of the pesticide issue. Their pr people focus on the absence of
much evidence (not none) on GM crops while ignoring the pesticides. We
should try to refocus the issue on the pesticides and GM as a pesticides
or sources of herbicides used on resistant crops . Bee behavior
modifications may be a deadly to a hive as is direct mortality.
The enclosed comments and references are from my report on honey bee
colony collapse "The Bacillus thuringiensis (Bt) toxin Cry1Ab caused
reduced foraging activity before and after treatment with syrup
containing the toxin. However,the Bt toxin produced less pronounced
impacts on bee behavior than did the chemical pesticides deltamethrin or
imidacloprid (18). Bt bacteria caused mortality in bees when fed in
broth cultures or sugar solutions (19). A number of purified Bt Cry
toxins have been studied in the laboratory to determine their toxicity
to honey bees and bumble bees. For the most part, those studies showed
little threat from the Cry toxins. However, sublethal effects on the
bees were not recorded in the experiments (20).Transgenic glyphosate
resistant canola pollen posed no threat to honey bees (21). Organic,
conventional and herbicide resistant Canola were compared regarding the
pollination by wild bees in Alberta, Canada. The herbicide tolerant
canola plots had the greatest pollination deficit
, while conventional and organic plots were equally well served by the
wild bees (22). Fuller studies are needed to evaluate the impact of GM
crops on sublethal effects such as learning and feeding behavior".
18. Ramirez-Romero,R,Chaufaux,J and Pham-Delègue,M. Effects of Cry1Ab
protoxin,
deltamethrin and imidacloprid on the foraging activity and the learning
performances of the
honeybee Apis mellifera, a comparative approach Apidologie 36 (2005) 601-11
19. Hilbeck,A and Schmid,J. Another view of Bt proteins-How specific are
they and what else
might they do Biopestic. Int. 2006,2,1-50
20. Malone,L and Pham-Delègue,M. Effects of transgene products on honey
bees (Apis
mellifera) and bumblebees (Bombus sp.) Apidologie 2001,32,287-304
21. Huang ZY,Hanley AV,Pett WL, Langenberger M. and Duan JJ. Field and
semifield evaluation
of impacts of transgenic canola pollen on survival and development of
worker honey bees. J
Econ Entomol. 2004 Oct;97(5):1517-23
22. Morandin,L and Winston,M. Wild bee abundance and seed production in
conventional,
organic and genetically modified canola Ecological Applications
2004,15,871-81

AgBioWorld, http://www.agbioworld.org April 11, 2007
Safety Assessment of Bt Crops for Adult and Larval Honeybees

- by Eric Sachs, Yong Gao and Jian Duan, Presented March 29, 2007,
Public Hearing, Subcommittee on Horticulture and Organic Agriculture

Summary

--Entomologists have not been able to determine the cause of CCD (colony
collapse disorder) in honey bees.  While the cause is not yet clear,
there is strong evidence that the production of specific insecticidal
proteins from the soil bacterium Bacillus thuringiensis (Bt) in crops to
control targeted caterpillar pests and beetles does not pose a risk to
honeybees.

--There is extensive information on the lack of non-target effects to
diverse groups of beneficial insects including honey bees and other
pollinators from Bt microbial preparations that contain Bt proteins.

--Bt proteins are ideal for use in organic production and in Bt crops
because they bind specifically to receptors on the mid-gut of sensitive
caterpillar pests  and have no deleterious effect on
beneficial/non-target insects under the conditions of use, including
predators and parasitoids of targeted caterpillar pests and honeybees.

--Scientists perform extensive honeybee safety assessments on all
insect-protected crops, including Bt corn and Bt cotton.  The Bt
proteins in these crops have been shown to have no adverse effect on the
honeybee.

--EPA risk assessments have demonstrated that Bt proteins expressed in
Bt crops do not exhibit detrimental effects to non-target organisms in
populations exposed to the levels of Bt proteins produced in plant tissues.

--Specific studies involving Cry1Ab provide strong evidence of the
safety of MON 810 Bt corn to the honeybee (similar studies have been
conducted with other Bt proteins in genetically modified crops).

--The EPA concluded that based on the weight of evidence there are no
unreasonable adverse effects of the Cry1Ab protein expressed in MON 810
Bt corn to non-target wildlife or beneficial invertebrates.




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