General Information

Event name: CA-92-008
Country: CANADA
Nature of the harmful event:
Seafood toxins
Event directly affected:
Toxicity detected: Yes (Approximate range: 213 - 3,604 µg STXeq /100 g)
Associated syndrome: PSP
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes
Event occurred before in this location: Yes (Alexandrium bloom is an annual summer event in these waters.)
Individuals to contact: HUPPERTZ, Béatrice , LEVASSEUR, Maurice

Location & Date

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Location: Latitude: , Longitude:
General location information: South coast St. Lawrence Estuary, Québec Region
HAB Area code(s): CA-07
Additional location information: Lower St. Lawrence Estuary and the north part of the Gulf of St. Lawrence, Quebec, Canada
Bloom event dates (yyyy/mm/dd): Event Date:1992-06-21
Start: 1992-06-02, End: 1992-09-16
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: Early June-mid September.


Causative organism known: Yes
Causative Species/Genus: Alexandrium excavatum (39,074 cells/L)
June 21.
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: Alexandrium excavatum observed between June 2 and September 16.
Event-related bibliography:

Environmental Conditions

Weather: Turbidity (NTU): Wind direction:
Stratified water: No Oxygen content (nL/L): Wind velocity:
Temperature (°C): 14.5 Oxygen saturation %: Current Direction:
Sechhi disk (m): Salinity: 24 Current Velocity: 0
Nutrient information:
Temperature Range During Event: Max: 17 °C, Min: 8 °C
Salinity Range During Event: Max: 30, Min: 16
Bloom location in the water column:
In situ
Growth Comments Alexandrium excavatum was found throughout the region, presumably as a result of in situ growth.
Additional Environmental information:

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Mya arenaria Saxitoxins STX eq 213 Bioassay-Mouse
Mytilus edulis Saxitoxins STX eq 3,604 Bioassay-Mouse
Kit used: Type of kit used:
Additional information: AOAC Mouse Bioassay.
Economic losses:
Management decision: Periodic closures of shellfish harvesting zones (harvesting prohibited at toxin values greater than 80 µg STX eq/100 g).
Additional harmful effect information:
Updated at 08:46 on 25 Sep 2013