Second Study Reveals Bt Corn May In Fact Kill Monarch Larvae

WASHINGTON--An Iowa State University study published online Aug. 19 in "Oecologia" revealed additional evidence that pollen from bioengineered corn may be lethal to Monarch butterfly larvae. Researchers John Obrycki and Laura Hansen found that Monarch butterfly caterpillars were seven times more likely to die after eating milkweed plants carrying pollen from Bt corn. "What this study tells us is that with naturally deposited pollen, there's a good probability you'll get some mortality," Obrycki said.

The study comes approximately one year after a Cornell University laboratory study showing that milkweed leaves artificially dusted with Bt corn pollen are toxic to Monarch larvae. Much like the Cornell study, the Iowa State findings have been dismissed as inconclusive by biotech industry representatives. Rich Lotstein, spokesman for Novartis [which engineered the two genetically modified strains of corn used in the experiment], said that although the research was conducted outdoors, the results are not indicative of what happens in a field environment. "The weight of the evidence of published and preliminary research indicates that milkweed within one meter of Bt corn fields are highly unlikely to be dusted with toxic levels of Bt pollen," he said.

Bt corn accounted for roughly 20 percent of the corn planted in the United States in 1999. Environmental groups such as Environmental Defense are calling for the Environmental Protection Agency (EPA) to require farmers to plant 40-foot wide "buffer zones" around Bt crops to reduce risks of contaminating other plants. EPA officials said they would review the new Iowa study, along with other scientific research as a broad assessment of health and environmental risks. For more information go to www.thecampaign.org or ens.lycos.com/ens/aug2000/2000L-08-22-06.html.