Vulnerability of tropical shellfishes against PSP contamination during bloom of Pyrodinium bahamense var. compressum

Accumulation of paralytic shellfish poisoning (PSP) toxins in representative shellfish samples of epifaunal, partially exposed benthic and infaunal nature in association with the toxic dinoflagellate, Pyrodinium bahamense var. compressum was in- vestigated. Shellfish and seawater samples were collected during the last quarter of 2007 and in 2008 in Sorsogon Bay, Philip- pines. All tissue samples were then analyzed for PSP toxins while cell density of P. bahamense var. compressum was determined in water samples. Results showed that epifaunal, partially-exposed benthic, and infaunal shellfish have remarkable differences in terms of PSP toxin accumulation. Epifaunal shellfish can accumulate PSP toxin of more than a thousand times compared to in- faunal shellfish with the latter negative for PSP toxin during P. bahamense var. compressum bloom.