KENNEWICK — Benton-Franklin Health District ordered the Columbia River shoreline from the boat launch at Howard Amon Park south to the confluence of the Yakima River closed Thursday due to toxic levels of cyanobacteria. Test results indicated elevated levels of the neurotoxin Anatoxin-a, which is especially dangerous for small children and animals.

Symptoms appear within 15-20 minutes after ingestion depending upon the size of the person/animal affected and the amount of toxins consumed. Exposure in animals may result in weakness, staggering, difficulty breathing, convulsions, and death. In people, signs may include numbness of the lips, tingling in fingers and toes, and dizziness. Exposure to Anatoxin-a can be fatal.

Recreational use should be avoided until levels drop below recommended guidelines. Visitors are cautioned to keep children and pets out of the water until further testing shows the toxins reduced to safe levels. The health district will be conducting weekly testing until levels are determined to be safe.

Toxins can accumulate in fish tissues, especially in the liver, kidneys and other organs. Exercise caution when considering eating fish caught in areas with a major cyanobacteria bloom. Before eating, remove internal organs, which may contain more of the toxin.