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Cyanobacteria confirmed in Tomahawk lagoon

Potentially toxic blue-green algae (cyanobacteria) has been collected from the Tomahawk lagoon in Dunedin, prompting a warning from the Otago Regional Council for people (and dogs) to avoid contact with the waters of the lagoon.

ORC took a sample of the algae yesterday after being informed of the bloom by a citizen scientist working there.
Signs have been put at the lagoon today near the beach access to warn the public of the risks associated with the bloom, which is mostly at the bottom lagoon, and has high levels of cyanobacteria.

The lagoon discharges into the stream running onto the beach, so beachgoers should take care in this area.
Cyanobacteria can produce toxins that are harmful to humans and animals if swallowed or through contact with skin. Exposure to cyanobacteria may cause symptoms such as skin rashes, nausea, tummy upset, and tingling and numbness around the mouth or tips of fingers.

Anyone experiencing health symptoms after contact with contaminated water should visit their doctor. Public Health South is available on (03) 4769800 to provide health professionals with information about those symptoms.

Cyanobacteria occur naturally but can increase rapidly during summer months.
 
If the water is green or has floating bright green or blue scums, all contact should be avoided. Not all cyanobacterial blooms are visible to the naked eye and toxins can persist after the bloom has disappeared. 
 
ORC will continue to monitor and update the public as the bloom changes.

For more information please contact:

Rachel Ozanne
Environmental Resource Scientist
ORC
Ph 0800 474082
 
Communications contacts
 
ORC (Water quality issues)
Mark Peart 
Team Leader Communications – Channels
Ph 0800 474082 or 027 5312620
Email: mark.peart@orc.govt.nz
 
Southern District Health Board (public health issues):
Moira Finn
Senior Communications Advisor
Ph 03 476 9830 or 027 836 4718
Email: moira.finn@southerndhb.govt.nz
 
Dunedin City Council (Dog control issues)
Jamie Shaw
Senior Communications Adviser
Ph 03 4774000