Tetrodotoxin monitoring of non-commercial New Zealand bivalve molluscan shellfish

Tetrodotoxin is a potent neurotoxin found in a broad range of organisms from both marine and terrestrial environments. Historically, this toxin is most commonly associated with human poisoning events in Japan that result from... [ view full abstract ]

Tetrodotoxin is a potent neurotoxin found in a broad range of organisms from both marine and terrestrial environments. Historically, this toxin is most commonly associated with human poisoning events in Japan that result from the consumption of incorrectly prepared pufferfish. There is currently heightened awareness of the presence of tetrodotoxin in bivalve molluscs due to recent observations, and its potential as a food safety issue. It has been reported in Japanese scallops, New Zealand clams, Greek mussels, and British mussels and oysters. No human illnesses have been attributed to the presence of tetrodotoxin in New Zealand shellfish. To help assess the risk, EFSA is currently preparing a scientific opinion on the evaluation of the toxicity of tetrodotoxin and analogues in bivalve molluscs and marine gastropods.

To better understand the food safety threat posed by tetrodotoxin in New Zealand shellfish, a baseline survey was conducted over a 16 month period. Shellfish samples were collected from multiple recreational harvest areas and monitored for this toxin using a recently developed HILIC-MS/MS method. In this presentation the results of these analyses will be presented and will include the levels detected, incidence in different shellfish species, spatial-temporal trends observed and analysis of historical shellfish samples. Together with an updated toxicity assessment, this information will help determine whether the presence of tetrodotoxin in bivalve molluscs represents a credible food safety issue.