Environmental groups are suing to stop the use of genetically modified crops on federal wildlife refuges in 10 Midwest states.
The lawsuit contends an environmental assessment completed earlier this year by the Fish and Wildlife Service was not adequate. That review found no environmental risk to planting genetically modified crops on refuges.
Attorney Kathryn Douglass says the federal review left many unanswered questions about how the GMO crops might impact wildlife, native grasses and and endangered species.
"It's our contention they haven't done enough environmental analysis," she said.
This lawsuit, filed on behalf of the Center for Food Safety (CFS), Public Employees for Environmental Responsibility (PEER), and Beyond Pesticides, is the third of its kind filed against the Fish and Wildlife Service across the country.
A Fish and Wildlife official says the agency can't comment until it has reviewed the lawsuit.