The Trump administration has reportedly approved the use of so-called cyanide bombs on public land. The practice, used by the US Bureau of Land Management (BLM) to control predator populations on public lands, was banned in 2023.

An April memorandum signed by the BLM and the Agriculture Department's Wildlife Services program shows that the bureau has effectively repealed the ban on the deployment of M-44s-spring-loaded poison traps. These traps are understood to disperse sodium cyanide powder when triggered.

Sodium cyanide is a highly toxic compound. The compound can be fatal if inhaled, swallowed or absorbed through the skin.

"M-44s are indiscriminate killers and cannot be used safely," Predator Defense, who published the memorandum, wrote in a statement.

"They are meant to kill coyotes - which any true conservation biologist can tell you is an exercise in futility - but they also kill endangered species, essential native predators, and countless beloved dogs, none of which can read warning signs."

"They have also poisoned countless people. It is only a matter of time until one kills a child."

M-44s have been used to minimize predation on livestock, manage wildlife diseases, prevent wildlife threats to human safety and control invasive species before the 2023 ban. Environmentalists have long argued that the tactic is inhumane, indiscriminate and dangerous to the public.

In 2017, a 14-year-old boy and his dog were accidentally sprayed by an M-44 in the hills behind their Idaho home. The boy survived, but the dog died at the scene.

The incident led to restrictions or bans on M-44 use in three states and environmental groups petitioned for a nationwide ban.

The first Trump administration reauthorised federal use of M-44s in 2019 but later reversed that decision due to sustained public outcry. In 2023, the Biden administration barred Wildlife Services from using M-44s on BLM lands nationwide.

The decision was celebrated by environmentalists.

The memo, however, appears to reverse the ban and states that Wildlife Services must provide a chemical application notification to the local BLM field office and/or district office prior to using pesticides restricted by the Environmental Protection Agency.

This includes M-44s.

A spokesperson for the BLM told Gizmodo that the memo identifies restricted-use pesticides "as tools that may be considered under existing law and environmental review" and does not itself authorize or expand use of M-44s.

The memo has sparked renewed concern from environmentalists and public safety advocates and several organisations have pledged to fight the decision.