The Tacoma-Pierce County Health Department has sent out a warning to northeast Lake Tapps residents and swimmers of a potentially toxic algae bloom.

“Health Department staff have sent a sample of the algae to a laboratory and the results should be available in the next week or so. In the meantime, we recommend you and your pets avoid areas with algae,” the department said in a press release sent out July 19. “If you don’t see algae, it should be safe to swim and waterski. Keep in mind as wind direction changes, the algae could move elsewhere in the lake.”

Toxic algae, also referred to as cyanobacteria or blue-green algae, can produce toxins that can harm or kill people and pets.

It’s naturally occurring, but “runoff from fertilizers, animal and human waste reach our lakes and contribute to algae growth,” the department said.

Signs of ingesting toxic algae include lethargy, vomiting, diarrhea, convulsions, general weakness and difficulty breathing, and can start to show even minutes after exposure.

“You should rinse off anyone or any pets exposed to toxic algae immediately. Monitor for signs of illness and seek medical treatment if symptoms occur,” the department stated. “For exposed pets, keep them from licking their fur to groom.”

Skin contact with toxic algae can also cause a rash.

If you see toxic algae, call the Health Department at (253) 798-6470.