Study: Genetically Engineered Pollen Kills Monarch Butterflies

New York - Today Environmental Defense re-stated its call for the Environmental Protection Agency (EPA) to protect monarchs and other butterflies from the toxins contained in genetically engineered corn pollen. A field study published today in the online version of the scientific journal Oecologia substantiates the results of a 1999 study published in Nature, which showed that pollen from Bt corn kills monarch butterfly caterpillers in the laboratory. Bt corn is genetically engineered to produce insecticidal toxins, with the goal of killing insect pests. Bt corn coats the leaves of wild plants growing near cornfields with toxic pollen, which butterfly caterpillars then eat.

“No one wants to tell their children what monarch butterflies used to look like. It’s time that EPA insist that the companies selling Bt corn take measures to protect monarchs and other butterflies from toxic pollen from Bt corn,” said Rebecca Goldburg, senior scientist at Environmental Defense.

In 1999, Environmental Defense petitioned EPA to restrict the planting of Bt corn in order to protect monarchs and other butterflies. Environmental Defense asked EPA and Bt corn-producers to require, through regulations or contracts with growers, that fields of Bt corn be surrounded by 40-foot wide borders of non-Bt corn. Because most corn pollen settles out within about a dozen feet of corn plants, such borders would dramatically reduce the flow of toxic pollen from Bt corn into butterfly habitats. Environmental Defense also sent letters to chief executive officers of Monsanto, Novartis, and other companies selling Bt corn, asking them to restrict planting.

“Planting buffer zones of Bt-free corn is an effective and practical way of protecting monarchs and other butterflies from toxic Bt pollen,” said Goldburg. “EPA already requires that farmers growing Bt corn plant 20% of their corn acreage in non-Bt corn, in order to slow the evolution of pests resistant to Bt toxins. Planting some or all of this 20% acreage as buffer zones would be only a small additional step. Unfortunately, both EPA and the companies selling Bt corn have refused to require buffers. Today’s study shows that continued inaction would clearly be lethal to monarch butterflies.”