FREDERICTON (GNB) – Dr. Jennifer Russell, chief medical officer of health, is reminding New Brunswickers to be aware of the potential health risks posed by blue-green algae that may be present in lakes and rivers used for recreational purposes.

“We want all residents to be active and enjoy the outdoors, but we also want them to understand and consider the potential risks of exposure to blue-green algae,” said Russell.

Blue-green algae are a natural component of New Brunswick’s aquatic ecosystems but, under certain conditions, can increase in numbers to form blooms which can appear blue-green, green, red, brown or yellow in colour. This typically occurs when the temperature begins to rise in late spring and early summer.

Not all blooms are harmful, but some blue-green algae can produce toxins, which can cause skin, eye and throat irritation. More serious health effects such as gastrointestinal illness can occur if toxins are consumed. Toxins can also be harmful to fish, wildlife, livestock and domestic animals.

“While enjoying any recreational water, there are always things you can do help protect yourself,” said Russell. “Algal blooms can be unpredictable, so it is important that people always check the water before entering. If a bloom is present, it is recommended that you avoid swimming or engaging in other activities that may involve contact with the water.”

Other safety advice includes:

  • Always supervise young children and pets in recreational waters.
  • Do not swallow lake or river water.
  • Bathe or shower immediately after swimming.
  • Do not enter the water with open cuts or sores.
  • Always wash your hands before eating.

The government advises pet owners that algae mats along the shore of lakes and rivers can also be toxic and particularly harmful to dogs. Algae mats look like clumps of vegetation, and can appear black, brown or dark green in the water. They can be attached to rocks or aquatic vegetation or may be floating in the water. On the shoreline, they may appear brown or grey once they have dried. Dogs are attracted to their odour and should not be permitted to eat vegetation or floating mats, as they can be lethal if consumed.

The government supports various blue-green algae research projects through the Environmental Trust Fund. These projects, which are underway in the Saint John River and several lakes in the province, are intended to build a better understanding of the distribution of blue-green algae and their toxins.

More information is about blue-green algae is available online.