Oregon Health Authority (OHA) issued a recreational use health advisory July 9th for Malheur Reservoir due to the presence of a cyanobacteria bloom and cyanotoxins above recreational use values for human exposure. The lake is in Malheur County.
People should avoid swimming and high-speed water activities, such as water skiing or power boating, in areas of the lake where blooms are as the major route of exposure in ingestion of water. Toxins are not absorbed through the skin. However, if you have skin sensitivities you may get a puffy red rash.
You are encouraged to visit Malheur Reservoir and enjoy activities such as fishing, camping, hiking, biking, picnicking, and bird watching. Boating is safe as long as speeds do not create excessive water spray. Sprays could lead to the risk of inhaling cyanotoxins.
Drinking water: Drinking water directly from areas of the lake affected by a bloom is especially dangerous. Toxins cannot be removed by boiling, filtering or treating water with camping-style filters. Contact campground management or the local health department with questions about water available at nearby campgrounds or day use areas. Not all private treatment systems are effective at removing cyanotoxins. If you do not use a well or public water system and draw in-home water directly from an affected area you are advised to use an alternative water source.
Children and pets: Children and pets are at increased risk for exposure because of their size and level of activity. Dogs can get extremely ill and even die within minutes to hours of exposure to cyanotoxins by drinking the water, licking their fur, or eating the toxins from floating mats or dried crust along the shore. This is regardless of a recreational use health advisory in place. Similar to dogs, livestock and wildlife can become ill and die after drinking from waterbodies, troughs or other sources of drinking water affected by blooms and potential toxins.
Symptoms: Exposure to cyanotoxins can be serious and cause a range of symptoms. Symptoms may be similar to food poisoning such as stomach cramping, diarrhea, nausea and vomiting. Symptoms may also be more serious, such as numbness, tingling, dizziness and shortness of breath. These symptoms may require medical attention. Dogs can experience weakness, difficulty walking, seizures, lethargy, loss of appetite and more. If your dog exhibits symptoms veterinary treatment should be sought as quickly as possible.
Fishing: Fish caught from areas where cyanobacteria blooms are present should have fat, skin and organs removed before cooking or freezing. Toxins are more likely to collect in these tissues. Fillets should also be rinsed with clean water.For health information or to report an illness, contact OHA at 971-673-0482. Learn more here.