Salmon company Tassal tried to block publication of report on antibiotic use, documents show

Tasmania's largest salmon company, Tassal, has sought to block the release of monitoring reports submitted to the state's Environmental Protection Agency (EPA) after having used more than two tons of antibiotics in two of its fish farms.

In early January 2022, Tassal and Huon Aquaculture reported outbreaks of vibrio, a bacterium which the Tasmanian Salmonid Growers Association says can cause infection with a "death rate high".

To treat the outbreak, Tassal used 675kg of a broad-spectrum antibiotic, oxytetracycline, at his Sheppards lease near Coningham, just south of Hobart. An internal memo obtained under Right to Information laws reveals that EPA staff reported that there was a “sticking point” in discussions with Tassal, which went back to the argument of the that the 2020 Prior Antibiotic Use Monitoring Report should not be made public.

The January 2022 memo to the Director and Chief 'EPA, Wes Ford, revealed there had been a long standoff with Tassal over the release of a September 2020 report into the use of 1.3 tons of oxytetracycline on the controversial 'lease' Okehampton Bay near Triabunna.

According to the EPA, Tassal provided "a number of legal reasons" for why the report should not be disclosed in its entirety, including that the information should be considered commercially confidential. The company objected to the release of details of how much antibiotics were used and how many salmon cages were treated.

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The EPA has notified Tassal of its intention to release the report on November 16, 2020 unless it can "provide additional justification why not". But the report remained buried until July 2022, when it was posted on the EPA's website without public notification.

A spokesperson for the EPA confirmed that the agency had been "in conflict" with Tassal "over the material contained in the report, and whether or not it should be released". They said the government had amended the management law of the Environment and Pollution Control in December 2022 to allow the Director of the EPA to disclose and publish "relevant environmental information".

A table in one of The documents reveal that the Tasmanian salmon industry has used more than 31.4 tonnes of antibiotics in marine concessions since 2003.

Sheenagh Neill, spokesman for Marine Protection Tasmania, said the use of antibiotics appeared to be increasing, which was 'extremely disappointing, given that vaccines s have available".

"Salmon producers need to up their game.

"Tassal has very good reason to wanting to keep the public in the dark about his poor farming practices and dumping tons of antibiotics into our public waterways: it makes them look bad. I'm glad the EPA didn't respect Tassal's wishes.

Tassal states on its website that before being slaughtered, salmon treated with antibiotics "must undergo a long weaning period, as required by authorities to make sure there is no residue. The regulatory offtake standard for salmon destined for the domestic market is 1,000 degree-days, a cumulative count based on water temperature. (If the water temperature is stable at 16°C, the threshold of 1000 degree-days is reached on the 63rd day.)

"Why a clearance of 1 Is 000 degree days required for salmon, yet anyone who fishes flathead has no idea about possible antibiotic residues in the fish they catch in the "wild"? Neill asked.