Toxicity of Cochlodinium type '78 Yatsushiro occurring in Yatsushiro Sea [Japan]

The toxicity of water- and fat-soluble fractions from frozen cells of Cochlodinium type '78 Yatsushiro, occurring in the Yatsushiro Sea on July 21, 1983, was examined. The water-soluble fraction showed toxicity on intraperitoneal injection into mice. The mice showed signs of ataxia and convulsions and cause of death was respiratory paralysis, characteristic of paralytic shellfish poison. Death occurred at a dose of 10 mg solids/ml or equivalent to 1 x 10 super(7) cells/ml. When the fat-soluble fraction was injected, a dose of 60 mg fats/ml or equivalent to 5 x 10 super(7) cells/ml caused ataxia and prostration. Death occurred several hours after injection but signs of paralysis were not seen with this fraction. The toxic potency per cell of Cochlodinium) in the water-soluble fraction was one-thousandth or less compared with that of Protogonyaulax catenella collected in Senzaki Bay, Yamaguchi Prefecture.