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Be aware of harmful algae blooms this summer

April 23, 2018

Increasing temperatures create potential for toxins in water

As summer approaches, the Oregon Health Authority is reminding outdoor enthusiasts to be alert for harmful algae blooms when recreating in Oregon lakes, rivers and reservoirs.

Most blooms are harmless but under the right conditions some can produce toxins capable of causing illness in people and animals.

If toxin levels are above OHA guideline values for human health, the agency issues a health advisory warning people to stay out of affected water to avoid illness. This year after evaluating current research, OHA is reducing the toxin guideline values to further protect the public. Although this change should not affect the number of advisories that may be issued, it could affect the length of time an advisory is in place. This is because it may take longer for toxins to drop below these reduced values.

Since only a fraction of Oregon’s fresh waters are monitored, OHA advises people to stay out of the water if it looks foamy, scummy, thick like paint and pea-green, blue-green or brownish-red in color. Exposure to toxins can cause skin rash, diarrhea, cramps, vomiting, numbness, dizziness and fainting. Children and pets are most vulnerable to illness due to their size and level of activity. Note that OHA guideline values are for human health; animals are much more sensitive than people. Within hours of being exposed to extremely low levels of the toxin, dogs can become gravely ill and even die.

Although toxins are not absorbed through the skin, people with skin sensitivities can develop a rash when wading, playing or swimming in or around a bloom. More serious symptoms occur when water is swallowed while swimming, or through inhalation of water droplets via high-speed activities such as water-skiing.

By being aware of signs of a bloom and taking proper precautions when a bloom is suspected, people can continue to visit their favorite lake, river or reservoir and enjoy water activities such as canoeing, fishing, camping, hiking, biking, picnicking, and bird watching. Boating is also safe when speeds do not create excessive water spray.

To learn if an advisory has been issued or lifted for a specific water body, you can visit the Harmful Algae Bloom website at healthoregon.org/hab or call the Oregon Public Health Division toll-free information line at 877-290-6767.

For health information or to report an illness, contact OHA at 971-673-0400. For campground or lake information, call the local management agency.

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 Media contact

Delia Hernández

OHA External Relations

503-522-7179

phd.communications@state.or.us

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