News release

Warm Temperatures May Cause Algae Blooms

Environment (April 2008 - Feb. 2021)
Health and Wellness

Nova Scotians should be mindful of blue-green algae blooms that may appear in rivers and lakes across the province during warm weather.

Also known as pond scum, blue-green algae can be identified by its blueish green, grassy or soupy appearance on the water's surface, and it may also produce a distinct odour. Although many forms of blue-green algae are harmless, some produce toxins which may pose a health risk for humans and animals.

People should not swim in, drink from, or eat fish from water sources where the algae is present. Water contaminated with algae should not be used to prepare or cook food, and boiling the water will not eliminate the toxins.

Algae blooms can occur naturally in the right conditions, or be caused by human activities that add nutrients to lakes or rivers.

"The risk to health is fairly low, but if you develop symptoms that persist, you should consult a physician," said Dr. Richard Gould, medical officer of health.

If water containing algae is swallowed, symptoms may include stomach ache, diarrhea, vomiting and nausea. Direct contact with skin from swimming may cause skin, nose, throat or eye irritations.

Nova Scotians who suspect an algae bloom can report it to the provincial Department of Environment.

For more information, visit the departments of Environment and Health and Wellness web sites at www.gov.ns.ca/nse/water/docs/BlueGreenAlgae.pdf and www.gov.ns.ca/hpp/environmental/ .