TOXICITY OF THE PUFFERFISH, FUGU-VERMICULARIS-VERMICULARIS, INHABITING TOKYO BAY

Eighty-six specimens (58 males, 28 females) of pufferfish, Fugu vermicularis vermicularis, were collected off Futtsu, Tokyo Bay, and the toxicity of various organs was assessed.More than half of the specimens were found to possess a toxic liver, the highest and average toxicity scores being 1, 500 and 132MU/g, respectively. The testis of this pufferfish, which has been reported to be non-toxic, was found to be weakly toxic, depending upon the specimen. Most ovaries were toxic, with the highest score of 5, 900MU/g and the average score 874MU/g. The muscles were non-toxic, except for a single, weakly toxic example.It was noted that the Tokyo Bay specimens maintained a fairly high toxicity level even after the spawning season, in contrast to the observations on other pufferfishes, in which the toxicity levels sharply decreased down after spawing.