A toxic dinoflagellate bloom and PSP production associated with upwelling in Golfo Nuevo, Patagonia, Argentina

Abstract

In 1980 Paralytic Shellfish Poison (PSP) was detected for the first time in Patagonia (Argentina), and has been recurring since during spring and summer .Human intoxications were recorded during the 1987/88 summer due to ingestion of mussels . In January, concentrations of 750000 cells 1 -' were observed, decreasing to 3100 cells 1 -' twenty days later . At the same time, values of 66 150 .Mouse Unit (MU) 100 g -' of meat were measured in Aulacomya ater (a bivalve mollusk) . A decrease in the concentration of toxic plankton resulted in a concomitant decrease in MU values . The mean detoxification time was 7 .6 days . However, mussels retained toxicity up to 50 days after the disappearance of cells .The upwelling of cold waters at the beginning of summer, could have been one of the causes that favoured a bloom of Alexandrium excavatum and of Prorocentrum micans . In March, an abundance of the diatom Skeletonema costatum coincided with high concentrations of silicate .

Intertidal macrozoobenthos in sandy beaches of Bahía Nueva (Patagonia, Argentina) and their use as bioindicators of environmental impact

“…Twenty-five years before our study, Escofet (1983) found that this group of organisms represented 70% and 80% of the species number and abundance respectively from the intertidal community of a Puerto Madryn beach (the 28 de julio site from this study). These percentages are in the same order of magnitude as our data despite the time elapsed between the two sampling periods and the expansive urban development in Puerto Madryn city since the 70s (Esteves et al, 1992;Esteves et al, 1997;Eyras et al, 1999;Gil, 2001). However, polychaetes found in this study are different from those recorded by Pastor de Ward (2000) in the Golfo San José, probably due to the geographic barrier ( Fig.…”

“…The development of the region has generated environmental pressure on the coastal zone, with decreasing water quality (Esteves et al, 1997), toxic phytoplankton blooms (Esteves et al, 1992), and increasing kelp debris on the beaches (Eyras et al, 1999). Gil (2001) pointed out that part of these effects could be attributed to industrial effluents from fishery factories as potential sources of organic enrichment.…”

Occurrence patterns of Alexandrium tamarense (Lebour) Balech populations in the Golfo Nuevo (Patagonia, Argentina), with observations on ventral pore occurrence in natural and cultured cells

“…Paralytic shellfish poisoning (PSP) in the North Patagonia region was produced by blooms of the dinoflagellate Alexandrium tamarense (Carreto et al, 1993(Carreto et al, , 1998aEsteves et al, 1992;Gayoso, 2001). Toxin concentrations of up to 50,000 mg STXeq/100 g have been found in mussels collected in that region (Carreto et al, 1998a).…”

Analysis of the hydrographic conditions and cyst beds in the San Jorge Gulf, Argentina, that favor dinoflagellate population development including toxigenic species and their toxins

“…Among the phytoplankton species proliferating in these high productive areas there are also harmful algal taxa. Harmful algal blooms of the toxic marine dinoflagellates Alexandrium tamarense, Alexandrium catenella and Gymnodinium catenatum, which cause the neurotoxic paralytic shellfish poisoning (PSP), are a recurrent phenomenon along the Argentinean coast (Carreto et al, 1985(Carreto et al, , 1998a(Carreto et al, ,b, 2008Esteves et al, 1992;Santinelli et al, 2002). Toxic diarrhetic shellfish poisoning (DSP) episodes caused by Dinophysis species have been also reported (Sar et al, 2010(Sar et al, , 2012, as well as the production of domoic acid (DA) by Pseudo-nitzschia species under field and culture conditions (Montoya et al, 2006;Negri et al, 2004;Sastre et al, 2007).…”