Harmful Algal Information System: Event FR-98-003

General Information

Event name:	FR-98-003
Country:	FRANCE
Nature of the harmful event:	High Phyto concentration
Event directly affected:	Shellfish
Toxicity detected:	Yes (Approximate range: 850 痢 STXeq / 100 g)
Associated syndrome:	PSP
Unexplained toxicity:	No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme:	Yes
Event occurred before in this location:	No
Individuals to contact:	SCHWEIBOLD Laura

Location & Date

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Location:	Latitude: , Longitude:
General location information:	Thau Lagoon, Western Mediterranean Coast. HAB Area code(s): FR-12
Additional location information:
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information:	late October- December

Microalgae

Causative organism known:	Yes
Causative Species/Genus:	Alexandrium tamarense (90,000 cells/L) late October Dinophysis spp. (800 cells/L) mid-November
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known:	µg/l
Additional bloom information:	During mid-November, concentrations of A. tamarense began to decrease in water when Dinophysis spp. was observed. A. tamarense was identified by Nezan (Ifremer) and confirmed by Fukuyo, who thinks there are two different species present- A. tamarense and
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:

Growth Comments

Additional Environmental information:

Toxin Assay Information

Species containing the toxin	Toxin type	Toxin details	Max. concentration	Assay type
Mussels (late October)	Saxitoxins	STX eq	850	Bioassay-Mouse

Kit used:

Type of kit used:

Additional information:

Economic losses:

Management decision:

The lagoon was closed to harvesting shellfish.

Additional harmful effect information:

During mid-November, PSP toxins lingered in mussels and clams (Ruditapes decussatus), but were not detected in oysters. During the same period, DSP mouse tests conducted at Ifremer were negative for all shellfish. In late November, with PSP results still

Updated at 12:47 on 2 Dec 2019