New fish-killing alga in coastal Delaware produces neurotoxins

UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
Daniel G Baden, Director (Creator)
Andrea J. Bourdelais, Research Associate Professor (Creator)
Jerome Naar, Research Associate Professor (Creator)
Carmelo R. Tomas, Associate Professor (Creator)
The University of North Carolina Wilmington (UNCW )
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Abstract: Ten fish mortality events, involving primarily Atlantic menhaden, occurred from early July through September 2000 in several bays and creeks in Delaware, USA. Two events involved large mortalities estimated at 1–2.5 million fish in Bald Eagle Creek, Rehoboth Bay. Samples from Indian Inlet (Bethany Beach), open to the Atlantic, as well as from an enclosed area of massive fish kills at nearby Bald Eagle Creek and Torque Canal were collected and sent to our laboratory for analysis. Microscopic examination of samples from the fish kill site revealed the presence of a single-cell Raphidophyte alga Chattonella cf. verruculosa at a maximum density of 1.04 × 107 cells/L. Naturally occurring brevetoxins were also detected in the bloom samples. Besides the Chattonella species, no other known brevetoxin-producing phytoplankton were present. Chromatographic, immunochemical, and spectroscopic analyses confirmed the presence of brevetoxin PbTx-2, and PbTx-3 and -9 were confirmed by chromatographic and immunochemical analyses. This is the first confirmed report in the United States of brevetoxins associated with an indigenous bloom in temperate Atlantic estuarine waters and of C. cf. verruculosa as a resident toxic organism implicated in fish kills in this area. The bloom of Chattonella continued throughout September and eventually declined in October. By the end of October C. cf. verruculosa was no longer seen, nor was toxin measurable in the surface waters. The results affirm that to avoid deleterious impacts on human and ecosystem health, increased monitoring is needed for brevetoxins and organism(s) producing them, even in areas previously thought to be unaffected. Key words: brevetoxins, Chattonella cf. verruculosa, Delaware, fish kills, harmful agal blooms. Environ Health Perspect 110:465–470 (2002). [Online 1 April 2002]

Additional Information

Bourdelais, A. J., Tomas, C. R., Naar, J., Kubanek, J., & Baden, D. G. (2002). New fish-killing alga in coastal Delaware produces neurotoxins. Environmental Health Perspect 110, 465–470. Retrieved from [Reproduced with permission from Environmental Health Perspectives]
Language: English
Date: 2009
Algal blooms--Delaware, Fish kills--Delaware, Marine toxins--Delaware, Neurotoxic agents--Delaware
Algal blooms--Delaware
Neurotoxic agents--Delaware
Marine toxins--Delaware
Fish kills--Delaware

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