Release
Department of Environment and Local Government, Department of Health
June 16, 2025
FREDERICTON (GNB) – The public is reminded that, although not all cyanobacteria (blue-green algae) are harmful, some produce toxins that can cause skin, eye and throat irritation. Ingesting these toxins may lead to stomach issues and can also harm pets, fish, wildlife and livestock.
“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 cyanobacteria,” said Dr. Yves Léger, chief medical officer of health. “New Brunswickers are encouraged to familiarize themselves with the appearance of cyanobacteria blooms in order to minimize risks for themselves, their loved ones and pets.”
Surface blooms are usually blue-green, but can also appear green, red or brown. Benthic mats form at the bottom of lakes and rivers, resembling clumps of vegetation, and appear black, brown or dark green in water. When dried on shore, they may turn brown or grey and can attach to rocks or aquatic plants.
“There are always things you can do to help protect yourself while enjoying recreational waters,” said Léger. “Cyanobacteria blooms can be unpredictable, so it’s important to always check the water and scan the shoreline before entering, and avoid swimming in areas where there are visible blooms or mats.”
Other safety advice includes:
• Always supervise young children and pets near recreational waters.
• Do not swallow lake or river water.
• Bathe or shower after being in recreational waters.
• Do not enter the water with open cuts or sores.
• Always wash your hands before eating.
Benthic mats, including those washed up on the shores of lakes and rivers, can be toxic and deadly to dogs if ingested. Dogs are attracted to their scent and should not be allowed to eat shoreline vegetation or floating mats. People should avoid handling benthic mats while wading, fishing or boating.
“The government continues to support various cyanobacteria research projects through the Environmental Trust Fund,” said Environment and Climate Change Minister Gilles LePage. “These projects, which are underway throughout the province, are intended to build a better understanding of the distribution of cyanobacteria and potential toxins.”
More information about cyanobacteria is available online.
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Media Contact(s)
Tara Chislett, communications, Department of Health, [email protected].
Vicky Lutes, communications, Department of Environment and Local Government, [email protected].