Under increasing pressure to help end a mice plague that has tormented regional communities for eight months, the government announced it has secured 5000 litres of the super deadly rodent poison bromadiolone.

Currently banned for agricultural use in Australia, the state has offered to provide it for free if the Australian Pesticides and Veterinary Medicines Authority approves it for use.

When announcing the measure, part of a $50 million government package to deal with the outbreak, Agriculture Minister Adam Marshall said the poison would be "the equivalent of napalming mice" across the affected regions.

But communities say they're concerned it will kill much more than that.

"If he thinks it is was going to napalm mice, well he better be prepared for the consequences of napalming vulnerable Murray Cod as well," Healthy Rivers Dubbo spokeswoman Mel Gray told AAP.

Murray Cod, a protected species listed as vulnerable by the federal government, are "voracious predators" that snack on anything they can fit in their mouths, she says.

But right now their diet is predominantly mice.

"Who can blame them - they're everywhere."

But that means, should bromadiolone be used, wild populations already on the brink of extinction could be finished off.

"There's a reason that bromadiolone is banned across the world," she said.

"This will absolutely jeopardise the remaining population of Murray Cod that we've got."

Wild birds - like eagles, kites and owls - snakes, and goannas are also at great risk.

Humans too.

"First Nations communities here are really concerned about bush tucker being impacted and becoming dangerous," Ms Gray said.

The poison is so dangerous because it is long-lasting, and when eaten by animals is stored in the liver and fatty tissue after they die, Edith Cowan University's Dr Rob Davis said.

Research conducted at the university found high levels of the poison in owls and snakes across Perth, where bromadiolone is approved for use in residential settings.

"That sort of raised alarm bells," Dr Davis told AAP.

"This is potentially spreading through the whole food chain when we use these products."

If the poison is used, he says it could set up even more favourable conditions for the next mouse plague.

"You could be seeing agriculture landscapes without owls, kites, snakes and goannas for a long time to come.

"We could lose all our natural pest control."

NSW Farmers is calling for primary producers to get a 50 per cent rebate on zinc phosphide, an alternative poison, instead.

Dr Davis agrees it is the "better of the two evils".

"There would be no other country in the western world that would approve this use of bromadiolone."

If approved by the APVMA, it will be the first time bromadiolone is permitted for this use in Australia since 2016.

Australian Associated Press