Tasmanian salmon companies are insisting their products are safe to eat while not directly answering questions about whether diseased fish are being sold for human consumption.

In recent weeks, a bacterial outbreak has led to the mass deaths of farmed Atlantic salmon from pens in southern Tasmania.

Combined with warmer weather, the bacteria outbreak was behind the deaths of at least 5,500 tonnes of fish dumped at southern Tasmanian waste facilities in February alone, and resulted in oily globules washing up on multiple beaches along the D'Entrecasteaux Channel in Hobart's south.

The Department of Natural Resources and Environment has previously said the bacterium didn't pose a "human or animal health, or food safety risk".

Protocol documents show 'as many fish as possible should be recovered'

Speaking at a press conference on Friday morning, federal Tasmanian independent MP Andrew Wilkie said 2014 documents on operating procedures from Huon Aquaculture have raised questions on whether diseased fish were being sold to consumers.

He said this was combined with a 2017 document, which provided information about company emergency procedures in the event of a significant risk to fish health.

The 2014 document specifies that in any large mortality event, "as many fish as possible should be recovered for harvest and processing", and any fish in which "the gills can still bleed is potentially recoverable".

"All recoverable fish must be kept separate and placed into an ice slurry ASAP,'" it reads.

It also says a health production manager will "determine whether the fish can be sent for processing".

The document also notes that if the mortality "occurs on a Friday or Saturday then the factory requires a minimum of 2 tonnes of recovered fish to arrange cost-effective processing".

Huon Aquaculture told the ABC the documents were outdated and produced under the business' prior ownership.

It said the company only harvested live fish for human consumption.

"Everything that hits the shelves is completely safe to eat," it said.

Huon Aquaculture did not provide the ABC with its current procedure.

Salmon Tasmania chief executive Luke Martin said the state's industry "only harvests live fish for human consumption".

"I don't know how much clearer we can be — the Tasmanian salmon industry only ever processes live fish perfectly suitable for human consumption," Mr Martin said.

"Like all good protein farmers, our salmon companies undertake multiple quality control checks throughout the harvesting and processing of their fish.

"These are long-standing processes that have been developed over decades and are routinely audited by federal government food safety authorities.

"The bacterium that has caused this recent mortality event, RLO [Rickettsia-like organisms], is not transferable to humans.

"The Tasmanian Director of Public Health has confirmed that the marine bacterium [Piscirickettsia samonis (P. Salmonis)] is a fish pathogen and does not cause human or terrestrial animal disease, or any food safety risk."

Here are some of the questions we asked of Huon Aquaculture:

Not all convinced

Mr Wilkie said the document was cause for serious concern.

"I do not accept that these are historic documents and are no longer valid because they are entirely consistent with what whistleblowers are telling us today," Mr Wilkie said.

He said an independent inquiry was needed in the wake of this information and the recent mortality events.

Peter George, an independent Franklin candidate, and a founder of anti-salmon group Neighbours of Fish Farming, said consumers had a right to know if they were consuming diseased fish.

"This industry has been shown to have no social licence whatsoever," he said.

"It's quite clear that this industry is on the nose, should get out of the water, and that's what we've been warning for the past 10 years."

Government MP Kerry Vincent said the salmon industry was "heavily regulated" and that he had "the greatest confidence" the sector would work through the current challenges it was facing.

"With a market that's so heavily regulated, everybody's looking at it, everybody's reporting on it. I don't think there's any opportunity for lack of transparency."

Don't panic, chemistry professor says

Oliver Jones, a chemistry professor at RMIT University, said the bacterium impacting salmon pens in Tasmania, Piscirickettsia salmonis, was "non-pathogenic to humans".

"There's no evidence that it causes disease in humans," Professor Jones said.

"It's quite nasty in fish, but in humans it doesn't seem to have any effect."

Professor Jones said he could understand the concern from the community, but that his message was simple.

"Don't panic," he said.

Focus on sector to continue throughout election

While the federal election hasn't yet been called, the salmon industry has already taken a strong focus in Tasmania, with both major parties backing in the sector.

Next week, the federal government is set to introduce amendments to the Environmental Protection and Biodiversity Conservation (EPBC) Act to ensure the future of salmon farming in Macquarie Harbour on the state's west coast.

The industry in Macquarie Harbour has been under a cloud since November 2023, after three conservation groups requested federal Environment Minister Tanya Plibersek review whether the industry has the necessary approvals under the EPBC Act.

Ms Plibersek is still considering the request and has not provided a time frame for her decision.

On Friday, Opposition Leader Peter Dutton confirmed the legislation will have his party's support — meaning it will pass through parliament, despite strident opposition by the Greens.

All three salmon companies operating out of Tasmanian waters — Brazilian multinational JBS; New Zealand's Petuna; and Canadian aquaculture giant Cooke, owner of Tassal — are owned by foreign multinationals.