Altered corn may affect aquatic ecosystems

CHICAGO, Nov. 14 (UPI) -- Corn genetically altered to kill the European corn borer could potentially harm the U.S. Midwest's aquatic ecosystems, researchers said.

Scientists at Loyola University in Chicago established that pollen, leaves and other plant parts from corn -- including genetically modified Bt corn -- are washing into nearby streams, the Chicago Tribune reported Wednesday.

When eaten by aquatic insects called caddisflies, these materials can stunt growth and increase mortality, researchers said. Caddisflies, a food for fish and amphibians, are related to the European corn borer, said Emma Rosi-Marshall, the study's lead author and an Biology and Natural Sciences assistant professor at Loyola.

The corn is altered to include a gene from the micro-organism Bacillus thuringiensis, which produces a toxin that kills pests, including the European corn borer. The U.S. Environmental Protection Agency tested its impact on a crustacean but not on insects more closely related to the target pests.

"When the European corn borer eats (Bt corn) and dies, it reduces the need for pesticides. But these closely related caddisflies might be affected, too," said Rosi-Marshall. "The extent to which aquatic ecosystems are affected depends on lots of factors but we feel these kind of unanticipated effects need to be investigated."