Science Inventory



HILBORN, E. D. *CYANOBACTERIA AND THEIR TOXINS. Presented at 1st Biennial Conference on the International EcoHealth Association, Madison, WI, October 07 - 10, 2006.


Cyanobacteria, or blue-green algae, are naturally-occurring contaminants of surface waters worldwide. These photosynthesizing prokaryotes thrive in warm, shallow, nutrient-rich waters. Many produce potent toxins as secondary metabolites. Cyanobacteria toxins have been documented as the cause of numerous wildlife, livestock, and some human poisoning episodes. Additionally, as cyanobacteria blooms decay, dissolved oxygen concentrations in water decline and fish kills may occur.

Reports of toxic cyanobacteria blooms are increasing globally. Although the frequency of blooms appears to be increasing, the role of increased awareness and of improved detection is unknown. Cyanobacteria occurrence generally increases with eutrophication and with warming of surface waters. When human and domestic animal populations congregate around surface water sources, their waste, and nutrients such as nitrogen and phosphorous enter the water. Local populations depend on these surface waters to supply drinking water, irrigation, fish, and recreation. However, as population densities increase, the occurrence of blooms increases, thus heightening the risk of human and animal exposure to cyanobacteria toxins.

The characteristics of cyanobacteria and their toxins will be summarized. Their occurrence will be discussed in the context of anthropogenic activities. An overview of the adverse effects of cyanobacteria on ecosystem, animal, and human health will be provided.

This is an abstract of a proposed presentation and does not necessarily reflect EPA policy.

Record Details:

Product Published Date:10/07/2006
Record Last Revised:12/20/2006
Record ID: 156749