Lone Lake near Langley has been closed to swimming due to a toxic blue-green algae bloom.

Island County Health Officer Roger Case, M.D., said high levels of toxic cyanobacteriam, also known as toxic blue-green algae, are now present in Lone Lake.

“Lone Lake is currently unsafe for people and pets,” he said in a news release. “Until further notice, do not swim or water ski or drink lake water. Keep pets and livestock away from the lake. Clean fish well and discard the guts and avoid areas of scum when boating.”

Cyanobacteria are microscopic in size. It forms colonies that can turn the water a blue-green color and may form surface scums. Some species of cyanobacteria produce a family of toxins called microcystins, which are heptapeptides that primarily affect the liver in animals and are known as hepatotoxins. 

Hepatotoxins such as microcystins target the liver where they can cause bleeding. Symptoms include nausea, vomiting, and acute liver failure.  Symptoms may take 30 minutes to 24 hours to appear, depending on the size of the animal affected and the amount of toxic bloom consumed.

Public Health will continue to monitor Lone Lake waters throughout the coming weeks to ascertain when the lake’s waters will be free of this algae and safe to resume swimming. Visit www.doh.wa.gov/ehp/algae or contact Kathleen Parvin at 678-7914 or 321-5111 ext 7914.