Residents near Wiser Lake south of Lynden are being advised to avoid water contact after a recent sampling detected high levels of microcystins, a toxin produced by algae, that may be harmful to people and pets.
The toxins were announced in a Friday, Aug. 16 news release by Whatcom County Health and Community Services.
The toxin levels exceed the recreational guidelines of the Environmental Protection Agency and Washington State Department of Health.
Ingestion of lake water is the primary human health concern, according to the release. Limited contact from boating or fishing is not a significant risk to people, but waterskiing, swimming or riding personal watercraft poses a greater risk, since water may be accidentally ingested.
Pet owners are advised not to let their pets swim in the lake, as pets often lick their fur after swimming and may ingest toxins while grooming.
Caution signage has been posted at Wiser Lake since 2019 due to consistently elevated toxin levels.
Microcystin is a toxin that primarily affects the liver and may cause abdominal pain, nausea, vomiting, headache, diarrhea, sore throat, blistering around the mouth and pneumonia. This and other algal toxins are naturally occurring, although human and animal activity can impact the severity of freshwater algal blooms. Nutrients in fertilizer, pet waste, agricultural runoff and wildlife waste provide food for algal growth.
For more information on algal blooms, visit nwtoxicalgae.org or epa.gov.
