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OHA News Release

Media contact:
Jonathan Modie
OHA Public Health 971-246-9139
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Health advisory issued September 16 for Willamette River

Visual observation of scum on river from southern end of Ross Island to Fremont Bridge

The Oregon Health Authority is issuing a health advisory today based on visual observation of scum on the Willamette River, extending from the southern end of Ross Island downstream to the Fremont Bridge in Multnomah County.

Water monitoring is underway to determine the species and amount of blue-green algae cells present in the river. The type of species in the bloom will help to identify whether the cells present are those with the potential to produce toxins harmful to humans and animals.

The Oregon Department of Environmental Quality is testing water samples taken from the river. People should avoid skin contact with water, as well as swallowing or inhaling water droplets, until results of tests are available. Drinking water directly from the Willamette River could be especially dangerous.

Exposure to toxins from blue-green algae can produce symptoms of numbness, tingling and dizziness that can lead to difficulty breathing or heart problems, and require immediate medical attention. Symptoms of skin irritation, weakness, diarrhea, nausea, cramps and fainting should also receive medical attention if they persist or worsen. Children and pets are at increased risk for exposure because of their size and level of activity.

The public will be advised when the concern no longer exists.

Oregon Public Health officials advise people living along the river that toxins cannot be removed by boiling, filtering or treating the water with camping-style filters.

People who draw in-home water directly from the Willamette River in the area affected by the advisory are advised to use an alternative water source because private treatment systems are not proven effective at removing algae toxins. However, public drinking water systems can reduce algae toxins through proper filtration and disinfection. If people on public water systems have questions about treatment and testing, they should contact their water supplier.

Oregon health officials recommend that people who choose to eat fish from waters where algae blooms are present remove all fat, skin and organs before cooking, because toxins are more likely to collect in these tissues.

Public health officials also advise that people not eat freshwater clams or mussels from affected water, and that Oregon Department of Fish and Wildlife regulations do not allow the harvest of these shellfish from freshwater sources. Crayfish muscle can be eaten, but internal organs and liquid fat should be discarded.

With proper precautions to avoid water contact, people are encouraged to visit the Willamette River and enjoy activities such as hiking, biking, picnicking, fishing and bird watching. Boating is safe as long as speeds do not create excessive water spray, which could lead to inhalation risk.

For local information about water quality or blue-green algae sampling, contact the Department of Environmental Quality at 503-693-5723.

For health information, to report human or pet illnesses due to blooms, or to ask questions about a news release, contact the Oregon Health Authority at 971-673-0400. For information about advisories issued or lifted for the season, call the Oregon Public Health toll-free information line at 1-877-290-6767 or visit the Harmful Algae Bloom website at www.healthoregon.org/hab and select “Algae Bloom Advisories.”

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