2-Plants: Monarchs will not eat enough Bt-pollen to get poisened

[GENET <genetnl@xs4all.be>]

-----------------------
genet-news mailing list
-----------------------

-------------------------------- GENET-news --------------------------------

TITLE:  Research Shows Biotech Corn Pollen Unlikely To Harm Monarch
        Butterfly Larvae
SOURCE: Associated Press
DATE:   August 27, 2001

------------------ archive: http://www.gene.ch/genet.html ------------------


Research Shows Biotech Corn Pollen Unlikely To Harm Monarch Butterfly Larvae

CHICAGO (AP) - A new study found that pollen from genetically altered corn 
poses little risk to monarch butterfly larvae, contradicting previous 
findings that led to calls to curb the spread of bio-engineered crops. The 
larvae digest the pollen when they eat milkweed. A 1999 lab study at 
Cornell University showing that pollen from the corn could poison larvae 
caused a public outcry in Europe and rallied environmentalists to demand 
limits on the crops. But the latest study, which will be discussed 
Wednesday at a meeting of the American Chemical Society, found that the 
larvae usually do not eat enough pollen for it to harm them.

"It's a negligible risk at best. They must consume considerable amounts of 
pollen to show an effect, and that amount of pollen rarely exists in 
nature," said Mark K. Sears, chairman of the Department of Environmental 
Biology at the University of Guelph in Canada. Sears and a team of 
scientists looked at how far pollen traveled in a cornfield, if monarch 
larvae were exposed to it and how much of it the larvae typically ate. The 
research, funded mostly by the Canadian government, took place on corn 
fields in Canada, Iowa, Maryland and Minnesota between 1999 and 2000.

The scientists saw no adverse effects except when larvae ate about 4,000 
pollen grains. At that point, they began to eat and gain weight more slowly 
than larvae that ate corn pollen that was not genetically altered. The 
symptoms suggested that their stomach linings were breaking down, Sears 
said. However, because there is an average of only 120 pollen grains per 
square centimeter of a milkweed leaf, "it's highly unlikely that larvae are 
going to be exposed to that much pollen to cause a measurable effect," 
Sears said.

Kevin Steffey, an entomologist at the University of Illinois who was not 
involved with the study, said Sears' work presents a more accurate study of 
larvae diets than past research has. "The questions are, 'Will they eat it 
in nature?' and 'Are they even going to be exposed to it?' Those questions 
were not asked in the previous studies," Steffey said.

Gary Rolfe, an ecology professor at the University of Illinois who was not 
involved with the research, called for more study. The biotech corn was 
approved for use before enough research was done to show its effects, he 
said. "We've rushed to get these varieties out without the ecological work 
being done," he said. "We just don't have all the answers we need."

Discovery of the biotech corn in taco shells last fall led to nationwide 
recalls of corn products. The crop's developer was Aventis CropScience, a 
Research Triangle Park, N.C.-based firm.



--


|*********************************************|
|                   GENET                     |
| European NGO Network on Genetic Engineering |
|                                             |
|             Hartmut MEYER (Mr)              |
|               Kleine Wiese 6                |
|           D - 38116 Braunschweig            |
|                 Germany                     |
|                                             |
| phone: +49-531-5168746                      |
| fax:   +49-531-5168747                      |
| email: genetnl@xs4all.be                    |
|*********************************************|