Postconsumption domoic acid generation by the diatom Pseudo-nitzschia multiseries as a factor in depuration models

Abstract

A theoretical analysis of the clearance of the neurotoxin domoic acid (DA) from molluscan shellfish, notably the blue mussel ( Mytilus edulis ), indicated that the depuration simulation did not account for the maximum accumulation of DA nor for the failure to eliminate all of the DA from the mussels in the anticipated time. Subsequent examination of relatively young, neurotoxin-producing cells of Pseudo-nitzschia multiseries concentrated 8.5- to 10-fold and reincubated in the dark, however, showed significant amounts of DA were produced within the first 24 h of incubation. The possible production of DA, after ingestion, could generate an additional contribution to the toxin burden in the mollusc, which, when included in the depuration simulation, would explain part or all of the observed disparity in the depuration experiment.