General Information

Event name: US-00-007
Nature of the harmful event:
Seafood toxins , Other ( Alexandrim present)
Event directly affected:
Toxicity detected: Yes (Approximate range: 80-1,115 g STXeq / 100 g.)
Associated syndrome: PSP
Unexplained toxicity: Yes (Irregular bioassay results for Monterey sample: confirmed as PSP by receptor binding assay.)
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes (California Department of Health Services Marine Biotoxin Monitoring Program.)
Event occurred before in this location: Yes (Although the magnitude and overal distribution of PSP toxicity varies from year to year, the Marin coast is always the focal point for any event.)
Individuals to contact: LANGLOIS, Gregg

Location & Date

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Location: Latitude: , Longitude:
General location information: From Estero Bay (San Luis Obispo County) to B, California.
HAB Area code(s): US-20 US-21
Additional location information: Central California Coast.
Bloom event dates (yyyy/mm/dd): Start: 2000-06-27, End: 2000-09-17
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: Detection date and Final date = first and last occurrence, respectively, of PSP toxins > 80 ug/100 g. Low positives (PSP toxins) observed approximately one week before alert level reached. Low numbers of Alexandrium also detected at this time, increasing over the following week and coinciding with increased toxicity.


Causative organism known: Yes
Causative Species/Genus: Alexandrium spp. ( cells/L)
We estimate relative abundance: low to moderate percent composition observed; abundant blooms nearshore are very rarely observed.
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: Co-occurring dominant species: Mix of diatoms (Eucampia, Coscinodiscus, Detonula, Chaetoceros) and dinoflagellates (Prorocentrum micans, Dinophysis spp., Gymnodinium splendens) , no dominant species.
Event-related bibliography: Documented in our monthly/quarterly reports.

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: Advected
Growth Comments
Additional Environmental information: Environmental conditions (relaxation event, southerly winds) associated with peak period of toxicity along Marin coast. Temperature and wind data are currently being processed.

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Mytilus edulis Saxitoxins STX eq 1,115 Bioassay-Mouse
Mytilus californianus Saxitoxins STX eq 813 Bioassay-Mouse
Crassostrea gigas Saxitoxins STX eq 546 Bioassay-Mouse
Kit used: No Type of kit used:
Additional information: Irregular bioassay results for Monterey sample: confirmed as PSP by receptor binding assay. First concentrations of PSP toxins >80 ug detected in late June along Marin Coast (north of Golden gate). Eventually elevated levels also detected northward (Bodega Bay, late August) and southward (Estero Bay and Monterey Bay, early July) of this area. Highest concentrations detected along the Marin coast.
Economic losses:
Management decision: Annual quarantine on sportharvesting of mussels was already in place (May - October 31). Managed alert system in commercial shellfish growing area reduced harvest area to inner portions of Drakes Estero (Marin County) until toxin levels decreased to accep
Additional harmful effect information: