The Centre for Food Safety (CFS) urges the trade not to import and sell puffer fish and food containing puffer fish. The public should not consume any part of puffer fish and any food containing puffer fish.
1. How puffer fish and food containing puffer fish are regulated in Hong Kong?
According to Section 54 of the Public Health and Municipal Services Ordinance (Cap. 132), all food for sale in Hong Kong, locally produced or imported, should be fit for human consumption. An offender is subject to a maximum fine of $50,000 and imprisonment for six months upon conviction.
2. Why are puffer fish and food products containing puffer fish dangerous?
Puffer fish mainly in the families Tetraodontidae and Diodontidae, and some fish in the groups of Canthigasteridae, Molidae, etc., possess a potent neurotoxin known as tetrodotoxin (TTX) which can cause muscle paralysis. People in severe intoxication may die from respiratory failure. So far there is no antidote for TTX poisoning. TTX is heat-stable and cannot be destroyed by cooking, freezing or drying.
3. Is the flesh of puffer fish safe to eat because it is claimed that TTX concentrates mainly in the internal organs and the skin of puffer fish?
Although TTX accumulates mainly in the viscera and the skin of puffer fish, some species of puffer fish contain a high level of TTX in their flesh. Moreover, the flesh of puffer fish could be contaminated with TTX from the viscera and the skin during processing. At present, there is no internationally accepted guideline, procedure and accreditation scheme for the preparation of puffer fish to ensure that the flesh is not contaminated with TTX.
4. Is farmed puffer fish guaranteed free from TTX?
There is literature reporting that TTX is still present in tissues (e.g. ovary and liver) of farmed puffer fish. Moreover, the Food Safety Commission (FSC) of Japan has evaluated the toxicity of farmed puffer fish and concluded that the mechanism of toxin production in puffer fish is still unknown, and the farming conditions for the reduction of the toxin level in puffer fish have not been officially established.
5. Can we ensure the safety of puffer fish through a sampling and testing scheme?
According to the US Food and Drug Administration, there is no adequate sampling scheme to ensure a safe lot of puffer fish since any single fish may contain a lethal dose of TTX. In other words, the absence of TTX in a fish sample cannot guarantee that other fish in the same lot are toxin free. Therefore, even with a sampling and testing scheme in operation, safety of puffer fish consumption is yet to be adequately assured.