Concerns have been raised by three key Tasmanian government agencies regarding the scientific evidence underpinning applications to use the antibiotic florfenicol in the state’s salmon farming operations. Documents obtained under freedom of information laws reveal that the Tasmanian Health Department, the Environment Protection Authority (EPA), and the Department of Natural Resources and Environment have all scrutinised the applications, particularly concerning the potential impacts on human health and the environment.
These agencies provided joint feedback to the Australian Pesticides and Veterinary Medicines Authority (APVMA) in November of last year. This feedback was prompted by an application to expand the use of florfenicol into the east coast region, specifically targeting Tassal’s Okehampton Bay lease for Atlantic salmon cultivation. This followed an initial approval for florfenicol use in the south-east region, also in November, with both applications submitted by Abbey Laboratories on behalf of the salmon industry.
Scrutiny of Florfenicol Applications
The joint response from the Tasmanian agencies highlighted a significant gap in the provided evidence. It stated, “There is public and scientific interest in florfenicol use in aquaculture, including consideration of matters such as human health, antibiotic resistance, environment and ecology.” The agencies expressed concern that “neither the current nor the previous application provides considered and robust evidence, relevant to Tasmanian circumstances, to address these matters.”
Furthermore, the government agencies argued that the merits of florfenicol had not been adequately established. This included a lack of scientific evidence confirming that “florfenicol’s safety is well established,” as claimed by the industry. Crucially, there was also an absence of Tasmanian-specific data to address potential environmental risks.
The agencies noted that while laboratory results were beginning to emerge, the residue monitoring program was far from complete. Consequently, the EPA had been unable to verify whether the purported benefits of florfenicol, such as high uptake in salmon and a short environmental half-life, were applicable to real-world conditions in Tasmania.
Potential for Over-Treatment and Regulatory Oversight
A significant concern raised by the agencies was the possibility that expanding florfenicol use to another region could “provide an avenue for fish to receive multiple treatments.” They pointed out that the initial approval for florfenicol in the south-east region did not mandate specific details on which groups of fish were to be treated, raising questions about the potential for repeated administration.
As of now, the application for florfenicol use on the east coast has not received approval. Neither the APVMA nor Salmon Tasmania has confirmed whether the application has been rejected or if it remains under consideration.
Industry’s Push for Florfenicol and Regulatory Challenges
The salmon industry had been advocating for the widespread use of florfenicol throughout 2025, a push driven by significant fish die-offs that occurred the previous summer due to the bacterial infection Piscirickettsia salmonis. While the APVMA regulates the use of florfenicol, Tasmanian agencies are responsible for environmental monitoring.
Recent monitoring results have revealed the presence of florfenicol in Tasmanian waters at distances exceeding 10 kilometres from the nearest salmon farm where it was being administered. The antibiotic was detected in various marine organisms, including abalone, lobsters, bryozoans, urchins, and whelks. Of the 840 wild fisheries samples analysed, 165 tested positive for florfenicol, with an additional 209 samples awaiting analysis.
These findings led the APVMA to threaten the revocation of the licence for florfenicol use, giving the salmon industry until March 2 to demonstrate compliance with trade criteria.
In a separate incident, one of the major salmon producers, JBS-owned Huon Aquaculture, reportedly notified Tasmanian regulators of its intention to use florfenicol off-label – meaning in a manner not specified on the product label – with only one week’s notice, prior to obtaining federal approval. This action drew a strong reprimand from a head of a Tasmanian department before a formal application was submitted to the APVMA.
At the time, the Tasmanian government supported this application. Chief Veterinary Officer Deborah McSweyn wrote that Piscirickettsia salmonis continued to pose a threat to salmon welfare and had “significant flow-on effects for our environment and communities.” She added, “I have read and endorse the executive summary provided in [the] Abbey Labs application summarising the responsible management of p. salmonis and the benefits of florfenicol in the treatment of these bacteria in an aquatic setting.”
Salmon Industry Defends Its Processes
Salmon Tasmania chief executive officer John Whittington has defended the scientific integrity of the initial florfenicol application. He stated, “The evidence is clear that it is a proven and effective treatment for P. salmonis that does not impact the environmental health of our waterways or affect the safety of fish caught from them.” Whittington further asserted that the APVMA application process is “robust and independent,” involving “rigorous analysis of evidence and strict consideration of environmental and health impacts.”
Greens Raise Concerns Over Haste
The Tasmanian Greens obtained the agencies’ response under RTI. Greens leader Rosalie Woodruff expressed that the documents indicated an excessive haste in seeking florfenicol approval. “The government supported the headlong rush to use florfenicol on a large scale in Tasmanian waterways, despite no relevant evidence being provided by the industry to back its claims about the antibiotic’s benefits and impacts,” Dr Woodruff commented. She added that while the industry was promoting early environmental testing results, government departments were concurrently questioning the adequacy of the monitoring program with the federal regulator.
The current permit for florfenicol use in the south-east region remains valid until August 31. During its first month of operation, up to 800 kilograms of the antibiotic were reportedly used in salmon pens in the D’Entrecasteaux Channel. No further data has been released to indicate the total extent of its usage since then.
