General Information

Event name: CA-88-004
Country: CANADA
Nature of the harmful event:
Seafood toxins
Event directly affected:
Toxicity detected: Yes (Approximate range: Maximum of 8000 ug STX eq/100 gr.)
Associated syndrome: PSP
Unexplained toxicity: Yes (Mouse deaths assigned to UMF (Unknown mussel factor) were also noted for some samples of cultivated mussels, The symptoms were atypical of those of PSP intoxication.)
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: No
Event occurred before in this location:
Individuals to contact: CEMBELLA, Allan

Location & Date

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Location: Latitude: , Longitude:
General location information: Gaspe, Quebec Region
HAB Area code(s): CA-09
Additional location information: The lower St. Lawrence estuary and the Gaspe coast bordering the northern Gulf of St. Lawrence. More specifically, toxic dinoflagellate blooms were observed in nearshore transects of the Gaspe current, from 0 - 5 km offshore, and within the Baie de Gaspe and the Baie of Chaleur.
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: An early summer bloom dominated by centric diatoms was followed by the appearance of low concentrations of toxic Protoqonyaulax tamsrensis (<100/litre) in June in the Baie of Gaspe. From mid-August to September 5, 1988, large flagellates tended to dominate in the phytoplankton community in the Gaspe region. This latter bloom contained higher concentrations (10,000 cells/litre) of P. tamarensis than that in early summer. Sinking cells of P. tamarensis were recovered in bottom sediment traps throughout October.


Causative organism known: Yes
Causative Species/Genus: Protogonyaulax tamarensis (Lebour) Taylor 1979 (100 cells/L)
< 100 cells/L in June, Baie of Gaspe
Protogonyaulax tamarensis (Lebour) Taylor 1979 (10000 cells/L)
Mid August to September
Co-Ocurring Species/Genus: Phalacroma sp. ( cells/L)
Dinophysis acuminata Claparède et Lachmann 1859 ( cells/L)
Dinophysis norvegica Claparède et Lachmann 1859 ( cells/L)
Chlorophyll concentration, if known: µg/l
Additional bloom information: The source of PSP in the region was definitively established as P. tamarensis. However, in August, particularly in the region of the Gaspe which includes the Baie of Gaspe, multispecific blooms dominated by dinophysoid species, including Phalacroma sp., D
Event-related bibliography:

Environmental Conditions

Weather: Turbidity (NTU): Wind direction:
Stratified water: Oxygen content (nL/L): Wind velocity:
Temperature (°C): Oxygen saturation %: Current Direction:
Sechhi disk (m): Salinity: Current Velocity:
Nutrient information:
Temperature Range During Event: Max: °C, Min: °C
Salinity Range During Event:
Bloom location in the water column:
Growth: Advected
Growth Comments Toxic dinoflagellate populations occurring in the Baie of Gaspe appeared to be advected from outside the bay, as a result of shoreward circulation within the Gaspe current. The evidence is a follows: blooms of Protogonyaulax were first observed outside th
Additional Environmental information: Water column was relatively unstratified in early summer; strongly subjected to storm and wind action in April and May. However, stratification developed in late summer within the Baie of Gaspe, where myticulture installations were placed in a area of water column depth <15m. Surface salinity 24 - 30 p.p.t.J surface temperature rose from 8 C in early May to 18 C by the end of August.

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Cultivated mussel Saxitoxins STX eq 8000 Bioassay-Mouse
Kit used: Type of kit used:
Additional information:
Economic losses:
Management decision: Large sections of the lower St. Lawrence estuary and Gaspe coast were closed to the commercial and recreational harvest of shellfish, due to levels of PSP which exceeded 80 ug STXeq/100 g.
Additional harmful effect information: No visible water discolorations ("red tide") were associated with the occurrence of toxic species in the lower estuary and Gaspe coast. At many stations,PSP levels in late May began to exceed 200 ug STXeq/100 g in wild mussel populations, and toxicity climbed constantly throughout June to a maximum of 8,000 ug STXeq/100 g. PSP toxin levels in cultivated mussels in the Baie of Gaspe reached a maximum of 7,000 ug STXeq/ 100 g in late June, then fell to gradually to levels nearly undetectible by mouse bioassay during mid-summer. A secondary peak of up to 3,000 ug STXeq/100 g was observed in late August to early September. Mouse deaths assigned to UMF (unknown mussel factor) were also noted for some samples of cultivated musselBJ the symptoms were atypical of those of PSP intoxication.
Updated at 06:36 on 25 Sep 2013