Lipophilic Toxins in Chile: History, Producers and Impacts

Abstract

A variety of microalgal species produce lipophilic toxins (LT) that are accumulated by filter-feeding bivalves. Their negative impacts on human health and shellfish exploitation are determined by toxic potential of the local strains and toxin biotransformations by exploited bivalve species. Chile has become, in a decade, the world’s major exporter of mussels (Mytilus chilensis) and scallops (Argopecten purpuratus) and has implemented toxin testing according to importing countries’ demands. Species of the Dinophysis acuminata complex and Protoceratium reticulatum are the most widespread and abundant LT producers in Chile. Dominant D. acuminata strains, notwithstanding, unlike most strains in Europe rich in okadaic acid (OA), produce only pectenotoxins, with no impact on human health. Dinophysis acuta, suspected to be the main cause of diarrhetic shellfish poisoning outbreaks, is found in the two southernmost regions of Chile, and has apparently shifted poleward. Mouse bioassay (MBA) is the official method to control shellfish safety for the national market. Positive results from mouse tests to mixtures of toxins and other compounds only toxic by intraperitoneal injection, including already deregulated toxins (PTXs), force unnecessary harvesting bans, and hinder progress in the identification of emerging toxins. Here, 50 years of LST events in Chile, and current knowledge of their sources, accumulation and effects, are reviewed. Improvements of monitoring practices are suggested, and strategies to face new challenges and answer the main questions are proposed.

Dinophysis acuminata or Dinophysis acuta: What Makes the Difference in Highly Stratified Fjords?

“…This trend is confirmed here: OA was not detected, and D. acuta was absent or just above detection levels (100 cells L −1 ) in the two fjords visited. Results here provide new evidence of the coexistence of D. acuminata strains with different toxin profiles in northern Chilean Patagonia (Los Lagos and Aysén regions), from 41.5 to 55.9° S (reviewed in [ 35 ]).…”

“…Blooms of the Dinophysis acuminata followed by blooms of D. acuta are common in coastal temperate seas. Some of the regions most affected are the European Atlantic Arc [ 25 , 53 ], the Patagonian fjords, Southern Chile [ 35 ], and the sounds and fjords in New Zealand South Island [ 54 ].…”

“…This species has been associated with all major historic DSP events (reviewed in [ 35 ]), and with contamination with okadaic acid (OA) in addition to dinophysistoxin 1 (DTX1) and pectenotoxin 2 (PTX2). Different strains of D. acuminata have been reported in Chile with profiles containing only PTX2 between the Atacama (33.5° S) and Bío Bío regions (37° S) [ 36 , 37 ] or with two groups of lipophilic toxins (DTX1 in addition to PTX2) in the southernmost region, Magallanes [ 38 ].…”

Disentangling Environmental, Economic, and Technological Factors Driving Scallop (Argopecten purpuratus) Aquaculture in Chile

“…Harmful algal blooms (HABs) have been detected at different aquaculture shellfish sites along the coast of Chile [5,71,72], forcing the establishment of sanitary protocols for domestic and export consumption [73]. To comply with European Union regulations and Food and Drug Administration (FDA) requirements, Chilean authorities established the Bivalve Mollusc Sanitation Program (PSMB).…”

Modelling the Spatial and Temporal Dynamics of Paralytic Shellfish Toxins (PST) at Different Scales: Implications for Research and Management

“…The direct and negative impacts of harmful algal blooms (HABs) on human health and economic sectors, mainly those related to aquaculture and the shellfish industry, are well-established (e.g., review by [1][2][3]). Chile has been severely affected by HABs, especially those caused by the dinoflagellate species Alexandrium catenella (Whedon and Kofoid) Balech, responsible for paralytic shellfish poisoning (PSP) [4].…”