Potentially toxic algae reported in Tomahawk Lagoon
High levels of potentially toxic blue-green algae (cyanobacteria) has been sampled 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.
As part of weekly water quality monitoring, the water sample collected yesterday returned a high level of cyanobacteria
from the upper Tomahawk lagoon.
Signs have been placed at the lagoon today to warn the public of the risks associated with the blue-green algae.
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. Southern DHB
Medical Officer of Health can be contacted on (03) 476 9800 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.
Otago Regional Council will continue to monitor and update the public as the bloom changes.
File image: Cyanobacteria in Upper Tomahawk Lagoon. March 2014.
Cyanobacteria Fact Sheet: