[Medical Q&A] Are these delicious seafood actually poisonous?

Author: Li Haijie, Associate Professor, School of Public Health, North China University of Technology

Reviewer: Yan Shengguang, Professor of School of Public Health, North China University of Technology

In recent years, as people have become more aware of the nutritional value of aquatic products, the proportion of aquatic products such as fish, shrimp, crab, and shellfish in their diet has increased year by year. However, food safety issues caused by aquatic products, especially food poisoning from aquatic products, have also attracted increasing attention.

At present, the most harmful natural toxins are tetrodotoxin, paralytic shellfish poisoning and ciguatera toxin. Tetrodotoxin is an alkaloid contained in pufferfish (commonly known as pufferfish) and other organisms. It is one of the most toxic neurotoxins found in nature, and its highest content is found in the ovaries, liver and intestines of pufferfish. Paralytic shellfish poisoning is a neurotoxin. After filter-feeding shellfish ingest toxic algae, the toxin is not excreted from the body and accumulates in the body. When people accidentally ingest it, paralytic poisoning occurs. Ciguatera toxin is a large molecular polyether neurotoxin that accumulates in the body of fish due to the large-scale ingestion of highly toxic algae.

The aquatic products that easily accumulate natural toxins include pufferfish (mainly containing tetrodotoxin), shellfish (mainly containing paralytic shellfish toxins and/or tetrodotoxin), deep-sea coral reef fish (mainly containing ciguatera toxins) and horseshoe crabs (mainly containing tetrodotoxin and/or paralytic shellfish toxins). Since the toxins contained in these aquatic products are highly toxic and cannot be distinguished by the naked eye from the appearance, texture, color, etc., once poisoned, the incubation period is short and there is no specific medicine, so vomiting should be induced immediately and medical treatment should be sought in time.