Recently, because of the warm weather, Northern Health has received several reports of cyanobacteria blooms in lakes across Northern BC. Cyanobacteria (also known as blue-green algae) are naturally occurring and can look like scum, grass clippings, fuzz or globs on the surface of water. Cyanobacteria can be blue-green, greenish-brown, brown, or pinkish-red, and often smells musty or grassy. Some cyanobacteria produce toxins, which can be released into the water when they die. During blooms, bacteria and toxin concentrations increase and may become a hazard.
People who touch visible cyanobacteria, or swallow water containing toxins from cyanobacteria, may get skin irritation, rash, sore throat, sore red eyes, swollen lips, fever, nausea, vomiting, or diarrhea. These symptoms usually show up within 1 to 3 hours and clear up in 1 to 2 days. Children may experience more pronounced effects. In severe cases, exposure can lead to liver damage or other serious outcomes.
People living near lakes, visitors and day users, are advised to take the following precautions:
- Avoid all contact with cyanobacteria blooms. If contact occurs, wash with tap water as soon as possible.
- Do not swim or wade (or allow your pets to swim or wade) in areas where cyanobacteria is visible.
- As a reminder, Northern Health recommends that visitors and residents do not drink or cook with untreated water directly from any lake at any time. Boiling lake water will not remove the toxins produced by cyanobacteria.
- Provide pets and livestock an alternate source of water. Pet owners should be cautious of allowing pets to roam off-leash near lakes, as drinking water with cyanobacteria toxins can make them sick.
Weather and wind conditions can cause cyanobacteria blooms to shift around a lake. Because blooms move, it is safest to take the most rigorous precautions around visible blooms, or in areas where blooms have happened before.
The Ministry of Environment and Parks (MoEP) also collects data on algae blooms across BC as part of the Algae Watch program. Observations and photos can be submitted using the online Algae Watch form. This will help MoEP identify and better understand cyanobacteria and algae blooms.
If you have concerns about cyanobacteria in drinking or recreational water, contact Environmental Health at 250-565-7322 or php@northernhealth.ca. More information can be found at Cyanobacteria blooms (blue-green algae) - HealthLinkBC