General Information

Event name: US-91-015
Nature of the harmful event:
Seafood toxins
Event directly affected:
Toxicity detected: Yes
Associated syndrome: ASP
Unexplained toxicity: No
Species implicated in toxin transmission (transvector): Razor clams and Dungeness crab.
Report the outcome of a monitoring programme: Yes
Event occurred before in this location: No
Individuals to contact: HORNER, Rita

Location & Date

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Location: Latitude: , Longitude:
General location information: Pacific coasts of Oregon and Washington., Oregon and Washington.
HAB Area code(s): US-22 US-23
Additional location information:
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: Probably October-November.


Causative organism known: Yes
Causative Species/Genus: Pseudo-nitzschia australis ( cells/L)
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: Presumed to bePseudo-nitzschia australis Frenguelli. Cultures from Oregon/Washington have not yet produced domoic acid; few phytoplankton samples are available, cell concentrations not known.
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 Not known, but may be part of a similar bloom in central California.
Additional Environmental information: Not known, but there are indications that water temperature is higher than usual.

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Razor clams Domoic Acid DA eq LC
Dungeness crab Domoic Acid DA eq LC
Kit used: No Type of kit used:
Additional information: Toxin assays done by U.S. Food and Drug Administration and National Marine Fisheries Service using acid or methanol extraction followed by HPLC (same method used in Canadian studies)
Economic losses:
Management decision: Closure of commercial and recreational harvest of razor clams on Oregon/Washington beaches; closed commmercial fishery for Dungeness crabs from northern California to northern Washington for nearly a month; spring, 1992, recreational harvest for razor
Additional harmful effect information: Razor clams are still toxic in mid-March 1992 with domoic acid levels of 30-60 ppm (regulatory closure level is 20 ppm); most toxin was found in the edible parts of the clams rather than in the viscera, but in crabs, most toxin was found in the viscera wi