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| Pfiesteria in TasmaniaRoutine monitoring by the CSIRO in August 2001 discovered a potentially toxic dinoflagellate called Pfiesteria at low-levels. This microscopic single-celled organism occurs in several parts of the world. It is known to be harmful to fish but has never had any known impact in Tasmanian waters.
CSIRO researchers detected Pfiesteria at two locations - near Triabunna and in the Huon Estuary.
Tasmanian government agencies are working in close consultation with CSIRO and other Commonwealth authorities to develop a response strategy.
Pfiesteria (feast-eerie-ah) is a microscopic aquatic organism that sometimes produces toxins that can injure or kill fish. The toxins may also cause health problems in people who breathe in the chemicals or get them on their skin.
First discovered in 1988, Pfiesteria has been known to occur in waters off the eastern seaboard of the United States, in New Zealand and some other countries. Species of Pfiesteria found in other countries have been responsible for large scale fish kills although over much of its range it does not seem to have caused a problem.
The organism, not previously recorded in Tasmania, could have been introduced to Tasmanian waters or it could possibly have been in our marine ecosystem for millions of years. It was discovered near Triabunna and in the Huon Estuary through routine scientific monitoring and has not been associated with any fish or human health problems in Tasmania.
Pfiesteria is a dinoflagellate. It is a single-celled alga. Its lifestyle is complex, covering 24 known stages. Pfiesteria can feed by producing toxins which it secretes into the water to make the prey sluggish. The toxins also injure the fish skin and open, bleeding sores and haemorrhaging often occur.
It has been found only to be a problem in the warmer months and only where salt and fresh waters mix such as estuaries, sounds and rivers near the coast. Typically it is found in poorly flushed waters where there is a lot of algae and high concentrations of fish. Nutrients such as nitrogen and phosphorus have been shown in laboratory testing to encourage the growth of Pfiesteria populations but research in this area is inconclusive.
When Pfiesteria produces toxins, they mix with the water and possibly the air. People may be at risk of brain damage and organ failure if the toxins are inhaled or absorbed through their skin. Exposure to Pfiesteria toxins is reported to have caused headaches, dizziness, a burning sensation on the skin, nausea, intestinal distress and short-term memory loss to some people who were directly exposed to the toxin. There is no evidence that people have become ill from eating fish or shellfish exposed to Pfiesteria.
There are no recorded cases of illness from eating fish or shellfish exposed to Pfiesteria. In general it is safe to eat seafood that appears healthy and that has been handled and stored properly after being caught. But people are urged to use common sense. Do not handle or eat fish from waters where numbers of fish are sick or dying. All farmed seafood in Tasmania passes through a stringent quality assurance program.
In the United States where Pfiesteria has been evident for a number of years, the advice from authorities is that swimming, boating and other recreational activities in coastal waters are generally safe. Some common sense precautions are recommended:
Avoid contact with the fish and water if there are significant numbers of fish that are dead or exhibiting lesions or signs of disease. Comply with any closures of water bodies by State or Local Government authorities.
Tasmanian government agencies are working in close consultation with CSIRO and other Commonwealth authorities to develop a response strategy. Experts are being consulted from around Australia. Tasmania already has in place World-class monitoring and management strategies for other toxic dinoflagellates which occur in our waters. We are now moving to ensure we can put similar strategies in place for dealing with this new potential problem.
Multi million dollar research projects are underway in the United States to develop mechanisms to manage the problem.
For related fish or environmental health issues or to report any fish kills please contact the Department:
Contact: Department of Primary Industries and WaterGPO Box 44
Hobart TAS 7001
Phone: 1300 368 550
For queries on health related issues, please contact the Public and Environmental Health Service:
Contact: Public and Environmental Health ServicePhone: 1800 671 738
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