General Information

Event name: NO-00-002
Country: NORWAY
Nature of the harmful event:
Seafood toxins
Event directly affected:
Toxicity detected: Yes (Approximate range: >16 ppm OA (up to 150 ppm OA).)
Associated syndrome: DSP
Unexplained toxicity: No
Species implicated in toxin transmission (transvector): Mytilus edulis.
Report the outcome of a monitoring programme: Yes (National Monitoring in Norway.)
Event occurred before in this location: Yes (Recurrent.)
Individuals to contact: DAHL, Einar

Location & Date

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Location: Latitude: , Longitude:
General location information: Norwegian coas from Sweden to Stad.,
HAB Area code(s): NO-09
Additional location information: The number of cells increased gradually and toxicity above safety level was detected in the middle of July at southern coast and occurred successively later further west and north along the coast. The bloom declined in late in the autumn, but the shell remained toxic through the rest of the year, and was still toxic in some areas in March 2001. ICES fishing area: IIIa & IV a.
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: July 2000-December 2000.


Causative organism known: Yes
Causative Species/Genus: Dinophysis acuta (4,700 cells/L)
Ceratium spp. ( cells/L)
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: About 2 g/L Chl in the period the shellfis µg/l
Additional bloom information: Dinophysis spp. occur annually in our coastal waters and DST in mussels above safety level is recorded each year. However, the spatial and temporal distribution of Dinophysis and related toxicity of mussels may vary much from one year to another. In 2000
Event-related bibliography: Dahl, E. and Johannessen, T. (2001). Relationship between occurrence of Dinophysis species (Dinophyceae) and shellfish toxicity. Phycologia 40 (3).

Environmental Conditions

Weather: Turbidity (NTU): Wind direction:
Stratified water: No Oxygen content (nL/L): Wind velocity:
Temperature (°C): Oxygen saturation %: Current Direction:
Sechhi disk (m): Salinity: Current Velocity: 0
Nutrient information:
Temperature Range During Event: Max: °C, Min: °C
Salinity Range During Event:
Bloom location in the water column:
Growth Comments
Additional Environmental information:

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Mytilus edulis Okadaic Acid OA eq ~ 200 ppm Bioassay-Mouse
Kit used: Type of kit used:
Additional information: Standard mouse bioassays were also positive.
Economic losses: Mussel plants were banned from harvesting
Management decision: Harvesting was stopped and the public was warned.
Additional harmful effect information: Very few intoxications were reported, the public was warned. No other effects registrated.
Updated at 03:24 on 2 Dec 2019