Both Sides of Biotech Battle Pounce on Butterfly Study

Both Sides of Biotech Battle Pounce on Butterfly Study

WASHINGTON, DC, May 21, 1999 (ENS) - A Cornell study released this week showing harmful effects on monarch butterflies that ate milkweed dusted with pollen from genetically modified Bt corn, brought a swift response from the biotechnology industry.

L. Val Giddings, Ph.D. vice president of food & agriculture for the Washington, DC based Biotechnology Industry Organization said, "Declining Monarch butterfly populations have been a concern for decades. It is known that many factors play a role in these declines. Even if the reported results are validated, there are strong reasons to believe they are not relevant to Monarch caterpillars in the wild.

The Biotechnology Industry Organization (BIO) represents more than 850 biotechnology companies, academic institutions and state biotechnology centers in 47 states and 26 nations.

Monarch caterpillars on a milkweed leaf dusted with pollen. (Photo by Photo by Kent Loeffler courtesy Cornell)

Writing in the May 20 of the journal "Nature," John Losey, a Cornell assistant professor of entomology noted that Bt-corn, has genes from the bacterium Bacillus thuringiensis (Bt) spliced into the plant genes. This new gene produces a protein which kills insects after the protein is ingested.

In Losey's lab tests, Monarch butterflies fed milkweed leaves dusted with pollen from a Bt-corn hybrid ate less, grew more slowly and suffered a higher mortality rate. Nearly half of their larvae died, while all of the monarch caterpillars fed leaves dusted with the non-modified corn pollen survived.

Giddings said in real life situations, Monarch butterflies would not encounter the Bt corn pollen. "Monarch migration and egg laying patterns ensure that the primary period of larval feeding and growth throughout nearly all the Monarch range takes place well before any nearby corn produces pollen. Ongoing monitoring of Bt corn fields by companies since their introduction further shows that very little pollen lands on adjacent milkweed leaves. It is thus highly likely that in the natural setting, outside the laboratory, most Monarch larvae would never encounter any significant amounts of corn pollen. This means the real potential for any negative impact is negligible."

"BIO members have long been working with groups concerned with Monarch butterfly conservation to address the threats they face," Giddings said. It is widely recognized that the principal threat facing the Monarch butterfly relates to loss of vital winter habitat in southern California and the highlands of central Mexico."

Meanwhile in Brussels, Belgium, European Union Environment Commissioner Ritt Bjerregaard announced Thursday that the EU would withhold the permit process for new genetically engineered Bt-maize but to take no action about previously approved Bt-maize varieties. Bjerregaard made the announcement in response to Losey's study showing transgenic Bt-maize pollen can kill Monarch butterfly larvae.

But that action was criticized by Greenpeace as not strong enough. Greenpeace urged Germany's Environment Minister Jürgen Trittin, who discussed the issue with the organisation in Hamburg thursday, to stop the growing of Novartis Maize (corn) in Germany, and, as president of the European Union’s Environmental Council to put a general moratorium for the release of genetically modified organisms on the agenda of the Council's next meeting in June.

Such a moratorium has been formally proposed by the Greek government.

"It is hard to understand how the Commission can put the approval of one Bt-Maize on hold, referring to the precautionary principle, but on the other side claim that there was no need to act on those varieties of genetically engineered maize which are already on the market and planted in Germany and Spain," Greenpeace spokesperson Benny Haerlin said.

The majority of existing plantings of transgenic corn in Europe is Norvatis "Event 176" or "Maximiser" and Monsanto’s "Yieldgard" (Bt-810) grown in Spain (around 20,000 hectares) and Germany (around 500 hectares). In the United States, about 27 million acres of genetically modified corn, mostly of the Bt variety, will be planted this season.