General Information

Event name: US-02-019
Nature of the harmful event:
Water Discoloration , High Phyto concentration , Seafood toxins
Event directly affected:
Planktonic life
Toxicity detected: Yes (Approximate range: Trace OA)
Associated syndrome:
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes (Virginia Dept. Health, Virginia Dept. Environmental Quality, Old Dominion University)
Event occurred before in this location: No
Individuals to contact: MARSHALL, Harold G.

Location & Date

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Location: Latitude: , Longitude:
General location information: Virginia shoreline inlets and streams along t, Virginia.
HAB Area code(s): US-10
Additional location information: 15 inlets, small bays, and streams along the Virginia shoreline of the Potomac River, scattered locations along the western margin of Chesapeake Bay between the mouth of the Potomac River and Rappahannock River.
Bloom event dates (yyyy/mm/dd): Start: 2002-02-17, End: 2002-05-15
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: Period February through May 2002 during persistent, non ending bloom.


Causative organism known: Yes
Causative Species/Genus: Dinophysis acuminata (236,000 cells/L)
Co-Ocurring Species/Genus: Prorocentrum micans (ca. 40,000 cells/L)
Composition and abundance varied with different sites and dates
Heterocapsa triquetra ( cells/L)
Chlorophyll concentration, if known: µg/l
Additional bloom information:
Event-related bibliography: sub-surface records in the lower Chesapeake Bay indicate below pycnocline transport into this region

Environmental Conditions

Weather: Turbidity (NTU): 0.4-1.5 Wind direction:
Stratified water: No Oxygen content (nL/L): 3.8-13.1 m Wind velocity:
Temperature (°C): Oxygen saturation %: Current Direction:
Sechhi disk (m): Salinity: Current Velocity: 0
Nutrient information:
Temperature Range During Event: Max: 20 °C, Min: 4 °C
Salinity Range During Event: Max: 21, Min: 10
Bloom location in the water column: Whole column
Growth Comments
Additional Environmental information: sub-surface records in the lower Chesapeake Bay indicate below pycnocline transport into this region, subsequent bloom occurred throughout the water column

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Dinophysis acuminata Okadaic Acid OA Trace LC
Kit used: Type of kit used:
Additional information: Toxin concentration reported by FDA.
Economic losses:
Management decision: None known
Additional harmful effect information: Blooms occurred in several inlets along the Virginia shoreline of the Potomac River, extending from February through May 2002
Updated at 02:52 on 6 Feb 2020