General Information

Event name: US-23-022
Country: UNITED STATES
Nature of the harmful event:
Seafood toxins
Event directly affected:
Shellfish
Toxicity detected: Yes (Approximate range: Maximum PSP toxins: 116-2143 µg/100g tissue.)
Associated syndrome: PSP
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes (Marine Biotoxin Program at the Washington State Department of Health, Office of Environmental and Health and Safety)
Event occurred before in this location: Yes
Individuals to contact: BORCHERT, Jerry , BARRY, Tracie

Location & Date

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Location: Latitude: , Longitude:
General location information: Washington State, Strait of Juan de Fuca and Bays,
HAB Area code(s): US-24
Additional location information: PSP was detected in Discovery Bay blue mussels briefly in mid-March triggering a recreational shellfish closure. PSP closures began again in mid-June in the open waters of the Strait and bays, with PSP peaking in mid-September in Discovery and Sequim Bays
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd): First detection: 2023-06-15, End: 2023-12-01
Additional date-related information: Another closure in mid-March

Microalgae

Causative organism known: Yes
Causative Species/Genus: Alexandrium spp. ( cells/L)
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information:
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: Whole column
Growth:
In situ
Growth Comments
Additional Environmental information:

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Blue Mussels Saxitoxins 2143 ug/100g Bioassay-Mouse
California Mussels Saxitoxins 795 ug Bioassay-Mouse
Geoduck Saxitoxins 1493 ug Bioassay-Mouse
Manila Clams Saxitoxins 1175 ug Bioassay-Mouse
Horse Clams Saxitoxins 116 ug Bioassay-Mouse
Littleneck Clams Saxitoxins 122 ug Bioassay-Mouse
Pacific Oysters Saxitoxins 225 ug Bioassay-Mouse
Kit used: No Type of kit used:
Additional information:
Economic losses: Recreational, commercial and Tribal ceremonial and subsistence shellfish harvests were interrupted, causing cultural and economic loss to Strait of Juan de Fuca Washington communities.
Management decision: WADOH closed shellfish harvesting at impacted areas to protect public health.
Additional harmful effect information:
Created at 10:07 on 8 Apr 2025
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