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 x 10(7) 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.
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Selected References
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- Baden D. G. Brevetoxins: unique polyether dinoflagellate toxins. FASEB J. 1989 May;3(7):1807–1817. doi: 10.1096/fasebj.3.7.2565840. [DOI] [PubMed] [Google Scholar]
- Baden D. G., Mende T. J., Bikhazi G., Leung I. Bronchoconstriction caused by Florida red tide toxins. Toxicon. 1982;20(5):929–932. doi: 10.1016/0041-0101(82)90081-2. [DOI] [PubMed] [Google Scholar]
- Baden D. G., Mende T. J., Lichter W., Wellham L. Crystallization and toxicology of T34: a major toxin from Florida's red tide organism (Ptychodiscus brevis). Toxicon. 1981;19(4):455–462. doi: 10.1016/0041-0101(81)90003-9. [DOI] [PubMed] [Google Scholar]
- Baden D. G., Tomas C. R. Variations in major toxin composition for six clones of Ptychodiscus brevis. Toxicon. 1988;26(10):961–963. doi: 10.1016/0041-0101(88)90261-9. [DOI] [PubMed] [Google Scholar]
- Bossart G. D., Baden D. G., Ewing R. Y., Roberts B., Wright S. D. Brevetoxicosis in manatees (Trichechus manatus latirostris) from the 1996 epizootic: gross, histologic, and immunohistochemical features. Toxicol Pathol. 1998 Mar-Apr;26(2):276–282. doi: 10.1177/019262339802600214. [DOI] [PubMed] [Google Scholar]
- Burkholder J. M., Noga E. J., Hobbs C. H., Glasgow H. B., Jr, Smith S. A. New 'phantom' dinoflagellate is the causative agent of major estuarine fish kills. Nature. 1992 Jul 30;358(6385):407–410. doi: 10.1038/358407a0. [DOI] [PubMed] [Google Scholar]
- Grattan L. M. Current status and future directions for the investigation and management of the human health effects of exposure to Pfiesteria piscicida or Pfiesteria-like dinoflagellates. Md Med J. 1998 May;47(3):148–151. [PubMed] [Google Scholar]
- Music S. I., Howell J. T., Brumback C. L. Red tide. Its public health implications. JFMA. 1973 Nov;60(11):27–29. [PubMed] [Google Scholar]
- Naar Jerome, Bourdelais Andrea, Tomas Carmelo, Kubanek Julia, Whitney Philip L., Flewelling Leanne, Steidinger Karen, Lancaster Johnny, Baden Daniel G. A competitive ELISA to detect brevetoxins from Karenia brevis (formerly Gymnodinium breve) in seawater, shellfish, and mammalian body fluid. Environ Health Perspect. 2002 Feb;110(2):179–185. doi: 10.1289/ehp.02110179. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pierce R. H. Red tide (Ptychodiscus brevis) toxin aerosols: a review. Toxicon. 1986;24(10):955–965. doi: 10.1016/0041-0101(86)90001-2. [DOI] [PubMed] [Google Scholar]
- Poli M. A., Mende T. J., Baden D. G. Brevetoxins, unique activators of voltage-sensitive sodium channels, bind to specific sites in rat brain synaptosomes. Mol Pharmacol. 1986 Aug;30(2):129–135. [PubMed] [Google Scholar]
- Scholin C. A., Gulland F., Doucette G. J., Benson S., Busman M., Chavez F. P., Cordaro J., DeLong R., De Vogelaere A., Harvey J. Mortality of sea lions along the central California coast linked to a toxic diatom bloom. Nature. 2000 Jan 6;403(6765):80–84. doi: 10.1038/47481. [DOI] [PubMed] [Google Scholar]
- Trainer V. L., Baden D. G. An enzyme immunoassay for the detection of Florida red tide brevetoxins. Toxicon. 1991;29(11):1387–1394. doi: 10.1016/0041-0101(91)90126-c. [DOI] [PubMed] [Google Scholar]