Research on marine toxins in Taiwan

Abstract

Some health issues of marine toxins in Taiwan are introduced here. From 1986 to 2002, the causative agents of seafood poisoning incidents have been reported to be tetrodotoxin (TTX, 30 outbreaks), paralytic shellfish poisons (PSP, 3 outbreaks), grass carp bile toxins (sporadically), ciguateric toxins (about 1 outbreak per year), excess dose of vitamin A (2 outbreaks), histamine (more than 5 outbreaks), pyropheophorbide a (1 outbreak), fish roe of Ascrossochelius paradoxus (1 outbreak), and allergens (sporadically). Among them, health issue of TTX in Taiwan is the most concerned problem. Therefore, TTX‐containing animals have been found to include puffer, goby, xanthid crab, gastropod, starfish, and flatworm. The dried dressed fish fillets produced from the non‐toxic puffers have been found to be adulterated by toxic puffers. The SDS‐PAGE and PCR methods for identifying species of puffers and their products have been developed. PSP was distributed in the purple clam, xanthid crab, and gastropod in Taiwan. The toxic alga Alexandrium minutum appeared in December–March. The toxin production of alga was affected by a variety of nutritional, environmental, and physiological factors. Most shellfish possessed high resistance to PSP, but the susceptibility of shellfish to the toxic alga was quite different depending on species. The food safety of animal bile juice is another important issue in Taiwan. The toxicity of bile juice was in the order of grass carp ≫ chicken ≫ snake. The major component of grass carp bile powder was 5α‐cyprinol sulfate (more than 90%) and those of other animals are bile salts. The toxic potencies of 5α‐cyprinol sulfate and 5α‐cyprinol induced acute kidney failure, but bile salts induced chronic liver dysfunction. Other marine toxins including diarrheic shellfish poisons (DSP), neurotoxic shellfish poisons (NSP), and amnesic shellfish poisons (ASP) are also very important from the health viewpoint in the world, though no poisonings due to those toxins have so far occurred in Taiwan.