The Department of Defence has found elevated levels of a toxic chemical once used in firefighting foam in animals sourced from a Gippsland wetland in eastern Victoria.

The tests revealed elevated levels of polyfluoroalkyl and perfluorotoalkyl substances (PFAS) in fish, eels and ducks from the Heart Morass wetland, which is connected to the East Sale RAAF base.

The Heart Morass wetland, near Sale, is popular with fishers and hunters.

Field and Game Australia own much of the wetland and spokesman Gary Howard, who helped Defence with their tests, said he was surprised by the results.

"The [EPA] press release was interesting because in the first part they were saying, if my memory serves me right, there was no danger to us having eaten these products. But they don't want us to eat any further, and to dispose of them," Mr Howard said.

"The issue there, from the hunter's point of view, is that nobody puts their birds away in a freezer and defines where they come from. We hunt all over the area."

East Sale RAAF base is one of 16 Defence sites across Australia being tested for toxic chemicals contained in firefighting foam. ( Commons: Goatindex )

The Gippsland community was first alerted to the unacceptable levels of PFAS chemicals in bore water at RAAF Base East Sale through community meetings.

But the Defence Department left it to the Environment Protection Authority to tell the community of the food contamination in a media release.

PFAS water contamination has already been found at Defence sites in Oakey in Queensland, Williamtown in New South Wales and Bullsbrook in Western Australia.

Authorities around the world have been scrambling to develop a plan to deal with the clean up of the toxins, which have experts concerned because they do not break down naturally in the environment.

Environmental watchdog says avoid eating animals

EPA Victoria has warned recreational fishers and game hunters to not consume animals caught at the Heart Morass wetlands.

Its Gippsland regional manager Stephen Lansdell told the ABC that people who have eaten animals from the wetlands are not considered to be at risk of any adverse health effects.

"EPA's risk assessment on that suggests that we just want to put precautionary advice out there not to eat eels, fish or ducks from Heart Morass," he said.

"But there's further assessment work happening, and then we expect the Department of Defence to come through with that further information come December."

Toxic PFAS chemicals have remained from when they were used in firefighting foam. ( Supplied: CRC CARE, file )

Duck hunter wants further tests done

Field and Game Australia's Gary Howard is concerned that ducks from other wetlands in Gippsland may also be affected.

He said he wants to see more information from the EPA and Defence.

"I suppose we're looking for an honest answer," he said.

"I can understand the elevated levels in the fish because they're basically trapped in there until there's a flood or the drains are opened and they can move back in to the Latrobe River, or in from the Latrobe River.

"But the ducks are a little bit different. They're very mobile."

The ABC understands the wetland's one commercial eel fisherman has had to cease work in the wetlands.