- The Washington Times - Wednesday, August 30, 2000

It was a big week for CBS television. The network aired the finale of the popular "Survivor" TV show and broke news about the Monarch butterfly edition of "Survivor" : Could butterflies survive being plucked from their natural environment and forced to live on a toxic island?

"It is the first field study to show that America's favorite insect, the monarch butterfly, can die from the pollen of gene-altered corn," reported CBS News about a new study from Iowa State University. But CBS overreacted. The new study is as much a "field study" and as realistic as "Survivor."

The alarm over biotech corn and Monarch butterflies started last year when Cornell University researchers reported pollen from so-called "Bt corn" killed Monarch larvae under laboratory conditions, including forcing the larvae to eat toxic pollen or not to eat at all.

Bt corn is genetically modified to carry a protein toxic to the European corn borer, a devastating pest. The protein is toxic to other moths and butterflies, but they don't eat corn pollen. Before Bt corn was approved, the Environmental Protection Agency concluded Monarch larvae would have little exposure to the pollen.

Amid last year's media hysteria "Engineered corn kills butterflies, study says," was USA Today's headline scientists said no data showed wild Monarch larvae would ever eat harmful amounts of the pollen. The unwarranted alarm subsided until last week.

Iowa State researchers led by a mere graduate student again reported Bt corn pollen was toxic to Monarch larvae in a "field study." Little "field work" was involved. Potted milkweed plants, the main food of Monarch butterfly larvae, were placed in and around Bt corn test plots. When Bt corn pollen fell on the milkweed leaves, the leaves were removed to a laboratory where tiny leaf sections were placed in lab dishes. The researchers put a Monarch larva on each section. Two days later, the researchers counted how many larvae died.

Some "field study." The larvae had no choice of food and couldn't move to clean leaf surfaces. Rain couldn't wash the pollen away. Larvae were placed on the top sides of the leaf sections, when in the wild, the larvae most likely would hatch on the undersides, away from pollen.

Still, only 20 percent of the larvae died after two days on the tiny laboratory islands covered with toxin. Even CBS' "Survivor" adventurers wouldn't try that.

Worse, the researchers used the type of Bt corn pollen most toxic to Monarch larvae. Pollen from this type, called "Event 176," is 50 times more toxic than pollen from other Bt corn varieties. But it accounts only for about 2 percent of Bt corn and is being phased out. Research shows Monarch larvae and other beneficial insects can withstand much higher doses of the pollen from the Bt corn usually planted.

Even so, the Iowa State researchers reported that beyond 1 meter from the cornfield, no sample of Bt corn pollen, including from around Event 176 fields, harmed the Monarch larvae.

Not surprisingly, the media overlooked these facts and not for the first time. A Canadian researcher reported last February that levels of Bt corn pollen at the edge of cornfields had no effect on Monarch larvae. Essentially no pollen was measured 5 meters away from cornfields. The study received almost no media attention.

There was scant coverage of a recent field study reporting Bt corn pollen didn't harm black swallowtail butterfly larvae placed on plants in and around Bt cornfields. Little attention was paid to a recent EPA report reviewing the safety of Bt corn for non-target species. The report convinced the antibiotechnology group Greenpeace to withdrew its lawsuit challenging the EPA's approval of Bt corn. The withdrawal wasn't covered.

There was some coverage last November when researchers from several universities met to present preliminary results of field studies of Monarch butterflies. None has been published yet because the researchers want to collect more data. But the early data indicated Monarchs aren't at risk from Bt corn.

New York Times' reporter Carol Kaesuk Yoon covered the meeting, but still reported this week, "Now, in the first study published on the subject since the debate began, scientists from Iowa State University say plants growing in and near the corn fields are being dusted with enough toxic pollen to kill monarch caterpillars that feed on them."

Ms. Yoon is technically correct by qualifying the study as "published." But did she simply forget covering the November meeting?

Also overlooked (ignored?) was Mr. Anthony Shelton, associate director of research at Cornell University, who was very critical of the Cornell study even though it was conducted at his own university. Mr. Shelton says the Iowa State researchers make "conclusions that exceed their data and some of their statements are simply off the mark."

"They do not provide any evidence that [a toxic] dose would be encountered by Monarchs in the field because they lack … the biological data on milkweed distribution and the occurrence of Monarchs," Mr. Shelton said. "More detailed and extensive field studies are being done by a group of independent scientists from the U.S. and Canada. So far, they have failed to see the effects predicted (by the Iowa State authors)," he added.

Apparently, Bt corn research is news only when researchers kill Monarch butterfly larvae in unrealistic lab conditions. It's not good science. But, like "Survivor," it makes good television.

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