Monitoring the presence of domoic acid in the production areas of bivalve molluscs

Algal biotoxins, chemical compounds produced by some microscopic algae, constitute the phytoplankton. The mussels, feeding on phytoplankton, can accumulate these compounds to become themselves toxic. There have been several cases of food poisoning by consumption of contaminated shellfish. Such food poisoning have pushed our health care system to provide monitoring of shellfish in the framework of the monitoring plans carried out by AASSLL. In this paper we report the results obtained monitoring the presence of amnesic shellfish poisoning biotoxins, like domoic acid and its isomers, produced by Pseudonitzschia algae. The analyses were carried out by using both the high-performance liquid chromatography- ultraviolet official method and an experimental method performed with a time-offlight mass spectrometer (ESI-TOF). The 100% of samples analysed by the official method have always been below the limits of sensitivity (except one sample), and the 65% of samples analysed by ESI-TOF showed the presence of domoic acid.