St. Louis Post-Dispatch | November 2, 1999 | Robert Steyer
The monarch butterfly has a lot more to fear than the pollen of genetically engineered corn, several experts said Monday.
The scientists, among 20 who will present reports today, said new field tests and past research indicate that monarch butterfly larvae are threatened more by pesticides and environmental damage than by biotech pollen.
Their findings may play an important role in the debate over bioengineered food because the monarch has become a rallying point for biotech critics.
The critics argue that federal government approvals have moved too quickly for biotech crops with built-in defenses against insects and weeds.
But most of the seven scientists speaking Monday said they believe the risk to these butterflies is small.
"If we thought there would be a big risk to the monarch, we wouldn't be behind this technology," said John Pleasants, assistant professor of zoology and genetics at Iowa State University.
"I don't think it's an issue," said John Foster, professor of entomology at the University of Nebraska, who has "no reservations" about planting or eating genetically engineered corn.
"Habitat destruction, mowing and spraying rights of ways with chemicals" have a greater impact on butterflies' health and safety, Foster said.
Dennis Calvin, professor of entomology at Pennsylvania State University, said his "impression is that the (biotech corn pollen) impact on monarchs is minimal."
The scientists have been studying the impact of biotech corn pollen on monarch larvae and on milkweed, the monarch's principal food. They spoke on a telephone conference call to several newspaper reporters that was arranged by a biotechnology trade group.
They offered a preview of research that will be presented today at a symposium in Chicago, adding that some research is preliminary and that some data are still being tabulated. The symposium is organized by Monsanto Co., several other biotech giants and trade organizations representing the agribusiness and biotechnology companies. They are paying these prominent academic researchers approximately $100,000 to examine larvae feeding behavior, the spread of pollen, the distribution of milkweed and the toxicity of biotech pollen. These tests follow a May report by a Cornell University researcher, who said monarch butterfly larvae exposed to pollen from biotech corn had higher death rates and lower growth rates than larvae exposed to pollen from standard corn. The researcher, John E. Losey, assistant professor of entomology, performed the tests in a laboratory. He said field tests were necessary to confirm his findings. Although some researchers criticized Losey's work, his article in the magazine Nature helped inflame anti-biotech opinion in the United States. It also had an impact in Europe, where consumers and politicians support labeling of gene-altered food and restricting - or even banning - biotech crop imports from the United States. "The bottom line is we need more data," Losey said Monday during the conference call.
He has done field tests on monarch larvae feeding habits independently of the industry-backed research. His results have been mixed. "I'm not reassured or more alarmed about (my original study) based on this data," Losey said. "It is too early to tell to rule out a risk or to tell how strong the risk will be." It's also too early to tell how the Chicago symposium will affect the American public, which has been more supportive of - or at least less antagonistic to - crop biotechnology than Europeans.
Critics are accelerating their campaigns, suing to stop the federal government from approving new biotech crops and threatening protests at the World Trade Organization meeting in Seattle in four weeks. They use the monarch - nicknamed "the Bambi of the insect world" by one entomologist - as a symbol. Recently, a coalition of environmental and anti-biotechnology groups began running full-page ads in The New York Times. The latest, entitled "Genetic Roulette," features a photo of a monarch amid an appeal for a five-year freeze on new releases of genetically-altered plants and animals. The scientists who spoke Monday made it clear that the monarch butterfly debate isn't as simple as critics or corporations suggest. For example:
- Different types of biotech pollen have different degrees of toxicity. For example, pollen from a Novartis corn used on few acres is much more toxic than pollen from widely used biotech corn developed by Monsanto.
- Corn pollen concentrations dissipate as they are blown into neighbor ing areas filled with milkweed. Potential danger thresholds for monarchs depend on pollen toxicity and the milkweed's distance from cornfields. Wind, rain, irrigation practices and other factors influence the concentration of pollen.
- Pleasants, the Iowa State researcher, found that pollen concentrations on milkweed at the edge of a cornfield could vary by 80-fold depending whether the milkweed plants were upwind or downwind of the field.
- In Nebraska, Foster found that 95 percent of the corn pollen had spread before the first monarch egg had been found, suggesting there was little chance monarchs would be affected. But Calvin's computer-model studies of six states found there could be big variations in the overlap of monarch egg-laying and pollen shedding.
"We don't know the impact on the population levels of the monarch," he said. "We don't have that data." The scientists said, as have their sponsors, that industry financing hasn't affected their work. "Industry has supported (my research) over the years," said Foster, "and I give them an honest answer that's not always the one they want to hear."
