Peterborough Public Health confirmed on July 21 that the suspected harmful algae bloom in Little Lake is a toxin producing blue-green algae bloom.

The beaches have been closed since July 14, and Public Health has announced the results of a water test taken by the Ministry of Environment, Conservation, and Parks (MECP).

“Elevated levels of toxins associated with blue-green algae have been detected and the beaches will remain temporarily closed,” says Julie Ingram, Manager of Environmental Health at Peterborough Public Health.

To learn more about the science of blue-green algae blooms, Trent Radio spoke to Claire Stevens, a graduate student at Trent University working on a PhD in the Biology department. Stevens’ research primarily focuses on cyanobacteria, or blue-green algae.

“Blue-green algae is a ‘catch-all’ term for cyanobacteria,’ says Stevens. “Cyanobacteria is a genus of algae which includes many species – many of which are toxin-producing.”

Stevens identifies that one of the most common bacteria produced by blue-green algal blooms is called ‘microcystis,’ which is what was identified in Little Lake. According to Peterborough Public Health, the MECP  confirmed the water sample taken from Little Lake had a total microcystin toxin amount of 169 µg/L, exceeding Health Canada’s recreational water limit of 10 µg/L.

Stevens identifies the wide range of short and long-term health effects that can occur due to exposure to the toxins present in Little Lake. Public Health has closed these two beaches and recommends caution when using the water for recreational purposes as the toxin can be harmful.

As of right now, there is no predicted date for the beaches to reopen. But, Public Health would like to have the beaches "reopened as soon as it is safe to do so," said Ingram.

To check Peterborough Public Health's beach testing results, visit their website.

Listen to the story below: