Cyanobacterial Toxins in the Water Environment
FR/R0009
March 2004

Summary

Cyanobacteria, also known as blue-green algae, are common members of the plankton of marine, brackish and freshwaters throughout the world. They also occur on rocks and soils and in symbioses with plants and fungi. The cyanobacteria possess a photosynthetic apparatus enabling them to perform photosynthesis as in algae and higher plants.

Cyanobacteria have the potential to produce mass populations in natural and controlled waterbodies. Such developments, leading to cyanobacterial blooms, scums and mats, are a common, but not invariable, consequence of eutrophication, the enrichment of waters with plant (and cyanobacterial) nutrients.

These large growths and accumulations of cyanobacteria are often aesthetically undesirable since they discolour the water and cause turbidity in recreational and amenity facilities. Furthermore, cyanobacteria are well documented as being able to potentially synthesise a large number of low molecular weight compounds which cause taste and odour problems. These substances often result in complaints regarding recreational and amenity waterbodies and the quality of raw and treated drinking water. Of particular concern are further low molecular weight compounds produced by cyanobacteria, which have been shown to have high toxicity to vertebrates, including mammals. These compounds, termed cyanobacterial toxins or cyanotoxins are largely unnoticed by users of waterbodies, when compared to the problems associated with taste and odour compounds, since the toxins are colourless and odourless.

This review describes the toxic compounds produced by cyanobacteria and how they are detected and quantified. It summarises what is known about their effects on human health, animal health and on other plants. Their fate in the environment is discussed and an overview of current and future research is provided.

This review contains 36 pages and has 30 references.

Copies of this report are available from the Foundation, price £15.00, less 20% for FWR Members.