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Cyanobacterial Toxin Effects on Mammals, Effects Due to Unidentified Toxins, and Characterization of the Toxin-Producing Cyanobacteria


Environmental Effects Research Laboratory, Toxicity Assessment Division

RO# Location
22.02.08.B8421 Research Triangle Park, NC 27711


Name E-mail Phone
Chernoff, Neil 919.541.2651


The potential of environmental cyanobacterial toxins to adversely affect the health of mammals, including wildlife, livestock, pets, and humans, is an issue of increasing importance due to the apparent increased global occurrence, range, and severity of hazardous algal blooms (HABs). Cyanobacterial blooms are complex, dynamic events and the necessary rapid testing for their potential toxicity is both difficult and problematic. The project focuses on the fact that most often, information on the toxins present is lacking, and extracts of the collected bloom materials are the sole source of toxicity evaluations. Exposure of the extracts to laboratory animals is often accomplished using the intraperitoneal route because of relative ease of administration and conservation of dosing material. However, extracts are complex and contain a wide variety of cyanobacterial chemicals in addition to known cyanotoxins. Bioassays that have compared the toxicity after exposures to extracts with that of the known toxins present have found that the toxicity of the extracts is greater than can be accounted for by the toxins alone. This has generally been interpreted as resulting from the presence of “unknown:” toxins. While the data support that conclusion, the nature of these toxins is unknown, and their identification is needed for the extract bioassay results to be considered relevant for potential hazard estimation. The problem of extracts is multi-faceted and involves the isolation and identification of the unknown toxins; their growth under different environmental factors; the effects of mixtures of toxins; and the effects of these toxins when administered by the relevant oral route.



Chernoff N, et al: Toxicity and Recovery in the pregnant mouse after gestational exposure to the cyanobacterial toxin, cylindrospermopsin. Journal of Applied Toxicology 31: 242-254, 2011

Chernoff N, et al: The course of toxicity resulting from exposure to the cyanobacterial toxin, cylindrospermopsin: Gross toxicity, histology, serum chemistries and hematology. Journal of Toxicology and Environmental Health 77: 1040-1060, 2014

de la Cruz A, et al: A review on cylindrospermopsin: The global occurrence, detection, toxicity and degradation of a potent cyanotoxin. Environmental Science Processes and Impacts 15: 1979-2003, 2013


Cyanobacteria; Hazardous algal blooms; Bloom extracts; Toxins; Toxicology; Mammals; In Vivo; Mixtures; Environment;


Citizenship:  Open to U.S. citizens, permanent residents and non-U.S. citizens
Level:  Open to Postdoctoral and Senior applicants
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