First Report of Okadaic Acid and Pectenotoxins in Individual Cells of Dinophysis and in Scallops Argopecten purpuratus from Perú.

Causative species of Harmful Algal Bloom (HAB) and toxins in commercially exploited molluscan shellfish species are monitored weekly from four classified shellfish production areas in Perú (three in the north and one in the south). Okadaic acid (OA) and pectenotoxins (PTXs) were detected in hand-picked cells of Dinophysis ( D. acuminata -complex and D. caudata ) and in scallops ( Argopecten purpuratus ), the most important commercial bivalve species in Perú. LC-MS analyses revealed two different toxin profiles associated with species of the D. acuminata -complex: (a) one with OA (0.3⁻8.0 pg cell ^-1 ) and PTX2 (1.5⁻11.1 pg cell ^-1 ) and (b) another with only PTX2 which included populations with different toxin cell quota (9.3⁻9.6 pg cell ^-1 and 5.8⁻9.2 pg cell ^-1 ). Toxin results suggest the likely presence of two morphotypes of the D. acuminata -complex in the north, and only one of them in the south. Likewise, shellfish toxin analyses revealed the presence of PTX2 in all samples (10.3⁻34.8 µg kg ^-1 ), but OA (7.7⁻15.2 µg kg ^-1 ) only in the northern samples. Toxin levels were below the regulatory limits established for diarrhetic shellfish poisoning (DSP) and PTXs (160 µg OA kg ^-1 ) in Perú, in all samples analyzed. This is the first report confirming the presence of OA and PTX in Dinophysis cells and in shellfish from Peruvian coastal waters.