General Information

Event name: US-19-002
Nature of the harmful event:
Seafood toxins
Event directly affected:
Toxicity detected: Yes (Approximate range: 0-289 g/100g)
Associated syndrome: PSP
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes (MA DMF Biotoxin Monitoring Program)
Event occurred before in this location: Yes (Nearly annual event)
Individuals to contact: O'NEIL, Terry

Location & Date

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Location: Latitude: , Longitude:
General location information: Nauset Estuary, Orleans and Eastham, MA,
HAB Area code(s): US-05
Additional location information: 1540 acre estuary on Cape Cod
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd): First detection: 2019-04-25, End: 2019-06-06
Additional date-related information:


Causative organism known: Yes
Causative Species/Genus: Alexandrium sp. ( 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: 18.9 °C, Min: 10 °C
Salinity Range During Event: Max: 33, Min: 19
Bloom location in the water column: Whole column
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 289 g/100g Bioassay-Mouse
Kit used: No Type of kit used:
Additional information:
Economic losses: Commercial and recreational shellfisheries in Nauset estuary closed for 42 days.
Management decision: Entire estuary (OC:2-OC:6) closed to shellfishing 4/25/19 through 6/6/19
Additional harmful effect information:
Created at 03:32 on 10 Feb 2020
Updated at 05:15 on 21 Apr 2020