Eighteen environmental advocacy groups are lobbying the Environmental Protection Agency to ban M-44s, the controversial spring-loaded devices filled with sodium cyanide and used primarily to kill coyotes and other predators.

The organizations filed a petition with the EPA on Thursday to ban the devices in the lower 48 states, citing the dangers posed to wildlife and people by the chemical pesticide.

The group, led by the Center for Biological Diversity and WildEarth Guardians, says the way the chemicals are being used doesn't comply with dozens of restrictions on the pesticide's label. The poison poses an "imminent hazard" to people, endangered species, and unintended targets such as pets, the coalition says.

"Cyanide traps are indiscriminate killers that just can't be used safely," said Collette Adkins, an attorney and biologist at the Center for Biological Diversity. "We're not fooled by the feds' ridiculous suggestion that bigger warning signs could somehow keep cyanide traps from hurting people, pets and imperiled wildlife. A permanent nationwide ban is the only answer."

The petition comes roughly six months after two incidents in the Pacific Northwest involving M-44s made national headlines and sparked a bill in Congress to ban the devices altogether. In February, a gray wolf in Wallowa County was killed by an M-44. Weeks later, a yellow lab in Pocatello, Idaho, was killed and a teenage boy was injured.

Two dogs in Wyoming were killed this spring by M-44s.

The U.S. Department of Agriculture oversees much of the predator control program nationwide through its Wildlife Services department, which deploys the M-44s. After the yellow lab was killed in Pocatello, the agency said it would temporarily stop using the devices in that state.

In Oregon, Wildlife Services agreed to stop using the devices in six rural counties in response to the wolf's death. The Legislature subsequently said state money could not be used to pay for M-44s.

The agency in June said it was conducting an "extended review" of the program nationwide and will continue to investigate the Idaho incident.

In 2016, M-44s killed 13,530 animals. That includes 321 family dogs, black bear, and other species not targeted for killing. The petitioners say that figure is "likely a significant undercount," because the agency doesn't collect complete data.

A spokesman said, in a statement, that hee USDA was aware of the petition and "understands the public's concern" about the devices. But the agency emphasized it follows the labeling and use restrictions outlined by the EPA.

"Wildlife Services has a long track record of safe and effective use of M-44s. Reviews by the Environmental Protection Agency and USDA Office of the Inspector General affirm that WS uses these devices, along with other predator management tools, safely and responsibly," the statement said.

M-44s are scented to lure predators like coyotes. When an animal tugs on the bait, the poison is shot into its mouth. According to the petition, when combined with the animal's saliva, hydrogen cyanide gas is created. "That quickly leads to central nervous system depression, cardiac arrest, and respiratory failure," the group said.

Wildlife Services is authorized to use the devices in 16 states, according to the agency spokesman. Several more states are allowed to use the devices without federal government involvement.

The petition applies to the lower 48 states, because only one approved use of the chemical compound exists outside the continental U.S. In an email, Adkins said the devices are used to kill arctic foxes "to protect endangered species" in Alaska. That use is "very different" than how M-44s are used in the lower 48 states, she said.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen