PORT TOWNSEND — Anderson Lake remains closed this week while the level of a potent toxin created by blue-green algae continues to climb.
Anderson Lake’s anatoxin-a level and is now at 39 times the safe level, according to preliminary data from King County Environmental Labs in Seattle, said Greg Thomason, Jefferson County environmental health specialist.
Results of samples taken last week found 38.7 micrograms per liter of anatoxin-a in Anderson Lake.
State recreational guidelines allow 1 microgram per liter of anatoxin-a.
The 410-acre Anderson Lake State Park around the lake remains open for hiking, biking and horseback riding.
Anatoxin-a is produced by blue-green algae, also known as cyanobacteria, which occurs naturally but which can begin, for unknown reasons, to produce toxins.
It is a quick-acting poison that can lead to death in people and animals within four minutes if ingested in high doses.
Anderson Lake — which was closed May 17, only three weeks after it was opened for the fishing season April 27, because of high levels of anatoxin-a — has a heavy bloom with no scum, Thomason said.
Only a trace of microcystin, another toxin created by blue-green algae, was found in the lake near Chimacum.
The safety threshold for microcystin — which can cause skin irritation, nausea and muscle weakness if touched and liver damage if swallowed over a long period of time — is 6 micrograms per liter.
Other lakes
Caution signs remain posted at Gibbs Lake, south of Port Townsend, and Lake Leland, north of Quilcene.
Both lakes have light blooms with no scum.
No toxins were detected in Gibbs, while a trace of anatoxin-a, and no microcystin, was found in Leland.
Visitors need a Discover Pass — either $10 for a day or $30 for a year — to park within Anderson Lake State Park.
Passes can be bought at any state park, where hunting or fishing licenses are sold, by phoning 866-320-9933 or by visiting www.discoverpass.wa.gov.
Toxin-producing blue-green algae has not been spotted in Clallam County.
Report algae blooms in Clallam County by phoning 360-417-2258, while Jefferson County blooms can be reported at 360-385-9444.
For more information about Jefferson County lakes, visit http://tinyurl.com/jeffersonlakequality or phone the office.
