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Blue Green Algae
- More toxic than cyanide!
Bluegreen algae toxins attack the liver and can cause hepatitis, cirrhosis
and cancer, as well as gastroenteritis and dermatitis
New found fame has escalated toxic blue-green
algae from a naturally occurring phenomenon, to one of the nation's most critical
water quality issues.
The presence of blue-green algae in Australian rivers, lakes, dams and estuaries
is widespread. Every mainland State has recorded outbreaks and the threat
they pose has been well publicised by the media.
Blue-green algae, known within the scientific community as Cyanobacteria,
grow naturally in most bodies of water. Microscopic plants. algae thrive on
a combination of nutrients, light, warmth and calm conditions.
Blue-green algae can be found at various depths within a body of water. However,
when conditions are favourable a bloom is triggered and the algae will appear
in abundance at the surface.
Algal blooms often take on the appearance of bright green sawdust before forming
a mat or scum on water surfaces. Their smell ranges from musty and earthy
odours to a putrid stench, which is most noticeable when decomposition begins.
A concern to health and the environment
Them are many species of blue-green algae but only a few are toxin producing.
In the non-toxic form, the algae make drinking water unattractive and smelly.
The toxic variety are a major health and ecological concern.
There are three main genera of toxin producing algae in Australia.
Anabaena produces an alkaloid nerve toxin, which
can cause muscular and respiratory disorders;
Microcystis and Nodularia produce peptide toxins
which can kill liver cells.
No human deaths have been recorded following consumption of water infected
by toxic algae. However, several ailments are associated with human consumption
or skin contact. These include gastroenteritis, liver damage and dermatitis.
There is also concern that the toxins promote liver
cancer. Extract from special article
has been contributed by the Institute of Natural Resources and Environment
Division of Water Resources, Griffith Laboratory, CSIRO.) |
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