Oregon Health Authority (OHA) expanded a recreational use health advisory issued August 17 for the Willamette River near Cathedral Park in Portland to extend upstream (south) to the Willamette Cove area near the SP&S Railroad Bridge.
The expanded advisory is due to the presence of a cyanobacteria bloom and cyanotoxins above recreational use values for human exposure.
People should avoid swimming and high-speed water activities, such as water skiing or power boating, in areas of the river where blooms are, as the major risk of exposure is from ingesting water. These toxins are not absorbed through the skin. However, if you have skin sensitivities you may get a puffy red rash.
Efforts will continue to collect samples next week to better define the extent of the public health advisory or to lift the advisory. People should be aware that the bloom and associated toxins may have originated upstream of Willamette Cove and could have spread downstream beyond the area around Cathedral Park. OHA recommends that people keep an eye out for visible signs of bloom in other areas of the river and stay out of the water in locations with visible scum.
People are encouraged to visit the Willamette River and enjoy activities such as fishing, camping, hiking, biking, picnicking, bird watching, canoeing and kayaking. 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 river affected by a bloom is especially dangerous. Toxins cannot be removed by boiling, filtering or treating water with camping-style filters.
Children and pets
Children and pets are at increased risk for exposure because of their size and levels 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.
Be aware that dogs can become ill and die from water intoxication after drinking excessive amounts of water while swimming or fetching objects for long periods of time. Intoxication is a potentially fatal disturbance in brain function resulting from an imbalance of electrolytes in the body. Water intoxication and heat stroke can cause similar symptoms as exposure to cyanotoxins.
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 any of these symptoms after swimming, seek veterinary treatment as quickly as possible.
Fishing
Fish caught from areas where cyanobacteria blooms are present may pose unknown health risks. Fat, skin and organs should be 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.
Source: Oregon Health Authority