Paralytic shellfish poisoning due to Pyrodinium bahamense var. compressa in Mati, Davao Oriental, Philippines

Abstract

On 26 August 1983, a single case of paralytic shellfish-poisoning (PSP) was reported in Davao City, Philippines. The poisoning was traced to ingestion of the green mussel <i>Perna viridis</i> Linnaeus, gathered from Balete Bay, Mati, Davao Oriental. Phytoplankton and zooplankton analyses on 12 October 1983 (47 d later), revealed the presence of the dinoflagellate <i>Pyrodinium bahamense</i> var. <i>compressa</i>, a cause of a series of red tides in the early and middle 1970's in Papua New Guinea, Sabah, and Brunei, and more recently, in Palau, and Western Samar and Leyte, Philippines. The dinoflagellate was not dominant; in fact the enumeration showed greater numbers of <i>Ceratium</i> sp., another dinoflagellate. Quantification of the neurotoxin by the standard mouse assay revealed a very high potency. Mussels collected from a new raft (transplanted in May 1983) had a toxicity of 7 960 mouse units (MU) per 100 g^-1 meat. Those from an old raft (transplanted in May 1982) had a toxicity of 9 620 MU per 100 g^-1 meat.