Benjamín A. Suárez-Isla, Laboratory of Marine Toxins, Program of Physiology and Biophysics, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 6530499, CHILE

Abstract

The Chilean coastline extends from the border with Perú (18° SL) to the Cape of Horn (54° SL). Chile's shellfish and finfish industries have experienced a major increase in marine phycotoxin problems in the last two decades. High levels of PSP and DSP have been reported in southern Chile (41°- 55° SL) that have been associated to the toxic dinoflagellate species Alexandrium catenella (PSP) and Dinophysis acuta (DSP). To date the paralytic and diarrhetic toxin groups have had the most severe public health and economic impact in Chile. This situation has made it necessary to close all natural shellfish beds from 44°SL southwards and to maintain nationwide monitoring programs. In addition to the presence of toxic dinoflagellates, yearly blooms of toxic diatom species (Pseudo-nitzschia australis) that synthesize domoic acid (DA), a toxin that can lead to Amnesic Shellfish Poisoning (ASP), have been observed. The percentage of shellfish samples with DA concentrations exceeding the regulatory level of 20 µg/g has increased steadily since 1997. These blooms have not been associated to date with cases of human intoxications, but constitute a serious potential threat to public health. In spite of these environmental constraints, shellfish aquaculture and exploitation of natural shellfish beds have grown steadily in the last ten years. Nowadays, over 110 different processing plants are certified to export their shellfish products for the European, US and Asian markets, totalling ca. US$ 90 million per year of exports and ca. US$ 30 million for internal markets. The impacts of HAB in Chile, new functional methods for toxin detection as well as national monitoring programs for shellfish and phytoplancton and management strategies will be discussed.