Ciguatera Fish Poisoning (CFP) causes the largest number of seafood-related food safety incidents in Australia. In NSW and southern QLD waters, CFP is mostly related to Spanish Mackerel (Scomberomorus commerson). Ciguatoxins (CTXs) produced by marine microalgae (Gambierdiscus spp), are polyether toxins that accumulate in fish and cause CFP when fish are eaten. CTXs are heat stable, odourless, tasteless, and toxic at low concentrations, therefore it is very difficult to distinguish toxic fish. In NSW, since 2014, 31 people have contracted CFP after consuming Spanish Mackerel caught locally, mostly through recreational fishing.

Validated commercial monitoring methods for CTXs are unavailable internationally, although research tools for CTX measurement have been developed. Regulatory methods for CFP prevention are to avoid certain fish species, fish of certain sizes (ie >10kg), or fish from certain regions. In Australia, effective prevention methods have not been clearly evaluated. This results in Spanish Mackerel that are safe to eat potentially being excluded from sale, resulting in significant losses (ie > ~$200k p.a in NSW). This project addresses this issue, which was identified as high priority in the Australian ciguatera research strategy formulated at a recent workshop (27-28th March, 2019).

In 2014, FRDC (Tactical Response) and the NSW Recreational Fisheries Trust funded an initial study on the incidence of CTXs in NSW Spanish Mackerel. CTX was present in flesh and liver samples (1-7% incidence), and was not clearly correlated with the weight of individual fish. This information showed that CFP risk management may require reassessment. This project will advance knowledge by: evaluating methods of detection of CTXs; determining detailed predictive data on CTX incidence; and evaluating environmental and biological factors associated with CTX in Spanish Mackerel to allow for an evaluation of risk assessment strategies. This information will benefit industry by enhancing consumer safety and industry confidence, and enabling the sale of safe Spanish Mackerel.