General Information

Event name: NO-92-001
Country: NORWAY
Nature of the harmful event:
Seafood toxins
Event directly affected:
Toxicity detected: Yes
Associated syndrome: DSP
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes
Event occurred before in this location: Yes (A few more dubious historical records. A yearly, more or less large scale and long lasting phenomenon since 1984 according to mouse bioassay. The phenomenom has never been so extensively monitored as in 1992.)
Individuals to contact: DAHL, Einar , VARRAN, Gesche Torp

Location & Date

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Location: Latitude: , Longitude:
General location information: , West coast.
HAB Area code(s): NO-08 NO-09
Additional location information: The most toxic shellfish were recorded at stations along the west coast.
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: In the months June-November toxic mussels were recorded at one or another station.


Causative organism known: Yes
Causative Species/Genus: Dinophysis spp. ( cells/L)
Most probably
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: Most probably Dinophysis spp., but a few examples of bad correlation between the observed concentrations of Dinophysis spp. and toxicity of mussels were recorded.
Event-related bibliography:

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 Along the southern coast there are some evidence that the algae and toxin problems are spread by advection. But along the west coast the 'hot spots' seems to be rather patchy which indicate local concentration of the algae and/or in situ growth.
Additional Environmental information: The problem seem to occur over a wide range of temperatures and salinities.

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Mytilus edulis Okadaic Acid OA eq Bioassay-Mouse
Kit used: Type of kit used:
Additional information:
Economic losses:
Management decision: Harvesting was locally banned. The public was warned against picking toxic mussels.
Additional harmful effect information: Toxins recorded above the action level according to mouse bioassay. Harvesting and consumption banned.
Updated at 04:05 on 2 Dec 2019