Amid growing concerns and lawsuits linking neonicotinoid pesticides with bee declines, Syngenta is asking the Environmental Protection Agency to increase the allowable levels of the company’s controversial neonicotinoid product thiamethoxam on certain crops.

Syngenta is seeking the change so thiamethoxam can be used as a spray on the foliage of alfalfa, corn, barley, and wheat. Currently, the pesticide is approved for use only as a seed treatment on those crops. In explaining its request, the company says, “Mid- to late-season insect pests are not controlled by seed treatment.”

The environmental group Beyond Pesticides says the move would be a “step backward for pollinator health.” Syngenta’s request “comes at a time when researchers are discovering that even ‘near-infinitesimal’ exposure to this class of pesticides can result in harm to honeybees and other wild pollinators,” the group says.

Syngenta’s action comes just days after Canadian beekeepers filed a class-action lawsuit against the company, claiming thiamethoxam and its breakdown product clothianidin led to more than $400 million in damages from 2006 to 2013. These alleged harms include bee deaths; reproductive, immunological, and behavioral effects in bees resulting in loss of hives; reduced honey yields; lower-quality honey; and contaminated hive equipment. “Chronic effects of the use of the neonicotinoids are felt by Canada’s beekeepers annually,” the suit states.

In the U.S., the environmental group Natural Resources Defense Council petitioned EPA earlier this summer to conduct an emergency review of the impacts of neonicotinoid pesticides on bees. The organization is urging EPA to finish the review within one year. The agency’s current schedule is to complete the safety review of this class of chemicals by 2019.

EPA has rejected calls from advocacy groups to ban neonicotinoid pesticides, saying there is no evidence that bees are being exposed to levels that would cause population declines. Instead, the agency announced in late August that it would require manufacturers to change their product labels to prohibit the use of neonicotinoid pesticides when bees are foraging or when plants are flowering. The labels, which could begin appearing as early as next year, must also display an icon showing that the pesticide is harmful to bees.

The European Union last year declared a two-year ban on three neonicotinoid pesticides, including thiamethoxam and clothianidin, because of concerns for bee health. In an ongoing lawsuit there, Syngenta is challenging that ban, saying it was based on a flawed process and an inaccurate assessment by the European Food Safety Authority.

“Growers depend on neonicotinoids and other crop protection products to increase crop productivity,” says Syngenta spokeswoman Ann Bryan. “And the scientific evidence clearly shows that bees and other pollinators can coexist safely with modern agricultural technologies like neonicotinoids when product labels are followed,” she says.

The case against neonicotinoids is complicated because scientists and pollinator experts agree that multiple factors—and not just pesticides—are affecting bee health. Other influences include parasitic mites, diseases, loss of habitat, poor nutrition, weather conditions, and a lack of genetic diversity in bee populations.