A health advisory was issued Friday for Detroit Lake, a reservoir 46 miles southeast of Salem on the North Santiam River.

Water monitoring confirmed the presence of blue-green algae and the potential harmful toxins they produce, according to the Oregon Health Authority.

Drinking the reservoir’s water, swallowing or inhaling water droplets, as well as skin contact with water, should be avoided. Drinking water directly from Detroit Reservoir is especially dangerous, and toxins cannot be removed by boiling, filtering or treating the water with camping-style filters.

Those who draw in-home water directly from Detroit Lake are advised to use an alternative water source, OHA officials said. Public drinking water systems can reduce algae toxins through proper filtration and disinfection.

With proper precautions to avoid water contact, visitors can 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, which could lead to inhalation risk.

Children and pets are at increased risk for exposure because of their size and level of activity. People who bring their pets fishing with them should take special precautions to keep them from drinking from or swimming in the reservoir.

Oregon health officials also recommend that people who 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 those tissues. Public health officials also advise that people not eat freshwater clams or mussels from Detroit Lake. Crayfish muscle can be eaten, but internal organs and liquid fat should be discarded.

Exposure to toxins can produce symptoms of numbness, tingling and dizziness that can lead to difficulty breathing or heart problems and require immediate medical attention, according to the OHA. Symptoms of skin irritation, weakness, diarrhea, nausea, cramps and fainting should also receive medical attention if they persist or worsen.

For local information, contact the U.S. Forest Service at 503-854-3366. For health information or to report an illness, contact the Oregon Health Authority at 971-673-0400.