View source for Pfiesteria piscicida

{{Taxobox | color = khaki
| name = ''Pfiesteria piscicida''
| image = 
| image_width = 240px
| regnum = [[Protista]]
}}

'''''Pfiesteria piscicida''''' is a [[dinoflagellate]] that some researchers claim is responsible for many [[Algal bloom|blooms]] in the [[1980s]] and [[1990s]] on the coast of [[North Carolina]].  ''[[Pfiesteria]]'' is named after Lois Ann Pfiester (1936–1992), who researched dinoflagellates,  and its [[specific epithet|species name]] means "fish-killer." The organism was discovered by JoAnn Burkholder at [[North Carolina State University]]. An in-depth story of her and her discovery can be found in ''And the Waters Turned to Blood'' by Rodney Barker.

==Life Cycle==  
While some peer-reviewed research by government and university dinoflagellate experts has shown that its living cycle is extremely complex (these scientists have found at least 24 different stages, spanning from [[cyst]] to several [[amoeba]]-like forms), other peer-reviewed research by government and university [[dinoflagellate]] experts has found only a simple life cycle with no [[toxic]] amoebic stage.  The original research claimed that the organism apparently moves through many different stages as environmental conditions require. However, the new research from [[2002]] claims the cycle is much simpler than previously thought, and that the true Pfiesteria is non-toxic (see external links).

==Toxicity==
Some peer-reviewed research based on advanced [[DNA]]-analyses shows that the organism lacks certain genetic structure to be capable of making the type of toxic proteins associated with typical dinoflagellates.  Researchers from the [[NOAA]] National Centers for Coastal Ocean Science, the [[National Institute of Standards and Technology]], the Medical University of South Carolina, and the College of Charleston (S.C.) have formally isolated and characterized the toxin in the estuarine dinoflagellete Pfiesteria Piscicida and also have identified how the organism transforms from a non-toxic to toxic state. The findings were published in the [[peer-reviewed]] science journal, Environmental Science and Technology, on [[11 January]] [[2007]].<ref>Peter D. R. Moeller, Kevin R. Beauchesne, Kevin M. Huncik, W. Clay Davis, Steven J. Christopher, Pamela Riggs-Gelasco, and Andrew K. Gelasco (2007): "Metal Complexes and Free Radical Toxins Produced by ''Pfiesteria piscicida''." ''Environ. Sci. Technol.,'' '''41''' (4), 1166 -1172. {{doi|10.1021/es0617993}}</ref>

==Human Health==
Very little research on the human health effects of Pfiesteria toxins has been conducted. At a multi-state workshop at the [[Centers for Disease Control and Prevention]] (CDC) in [[Atlanta, Georgia]], at the end of September [[1997]], attendees agreed on clinical symptoms that characterize the adverse health consequences of exposure to Pfiesteria toxins. These clinical features include:

*memory loss
*confusion
*acute skin burning (on direct contact with water); or
*three or more of an additional set of conditions (headaches, skin rash, eye irritation, upper respiratory irritation, muscle cramps, and gastrointestinal complaints (i.e., nausea, vomiting, diarrhea, and/or abdominal cramps).

With these criteria and environmental qualifiers (e.g., 20% of a 50-fish sample, all of the same species, have lesions caused by a toxin), it is likely that Pfiesteria-related surveillance data can better track potential illnesses.

Pfiesteria toxins have been blamed for causing adverse health effects in people who have come in close contact with waters where this organism is abundant. Since June [[1997]], the [[Maryland]] Department of Health and Hygiene has been collecting data from Maryland physicians through a state-wide surveillance system on illnesses suspected of being caused by Pfiesteria toxin. As of late October 1997, illness was reported by 146 persons who had been exposed to diseased fish or to waters that were the site of suspected Pfiesteria activity. Many of these persons are watermen and commercial fishermen.

The strongest evidence of adverse human health effects so far comes from case studies of two research scientists who were both overcome in their [[North Carolina]] laboratory in [[1993]]. They still complain of adverse effects on their cognitive abilities, particularly after exercising. [[Duke University Medical Center]] researchers conducted experiments on rats, which showed that the toxin appeared to slow learning but did not affect memory.<ref>http://www.ncseonline.org/nle/crsreports/marine/mar-23.cfm Report on Pfiesteria and Related Harmful Blooms:
Natural Resource and Human Health Concerns, [[Congressional Research Service]]</ref>

== References ==
{{reflist|2}}
{{USGovernment|sourceURL=a report by the [[Congressional Research Service]] (CRS), part of the [[Library of Congress]]}}

==External links==
* http://pubs.acs.org/subscribe/journals/esthag-w/2007/jan/science/ee_pfiesteria.html
* http://www.newsobserver.com/102/story/531575.html
* http://www.publicaffairs.noaa.gov/advisories/adv137.html
*[http://www.sciam.com/print_version.cfm?articleID=000CCCD6-8E5A-1D13-8B07809EC588EEDF Scientific American]
* [http://www.neuseriver.org/abouttheneuse/pfiesteria Neuse River Foundation]
* [http://www.nal.usda.gov/wqic/pfiest.html US Department of Agriculture]
* [http://www.enr.state.nc.us/files/pfies.htm North Carolina Department of Environment and Natural Resources]
* R. Wayne Litaker, Mark W Vandersea, Steven R Kibler, Victoria J Madden, Edward J Noga, Patricia A Tester (2002): Life Cycle of the Heterotrophic Dinoflagellate Pfiesteria Piscicida (Dinophyceae). ''Journal of Phycology'' '''38''' (3), 442–463. {{doi|10.1046/j.1529-8817.2002.t01-1-01242.x}}

[[Category:Dinoflagellates]]

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