Health officials warn people, pets away from water with blue-green algae

Biscuit, a Labrador retriever, exits the river at Tiscornia Park after retrieving a ball on Thursday in Sacramento.
Biscuit, a Labrador retriever, exits the river at Tiscornia Park after retrieving a ball on Thursday in Sacramento. jvillegas@sacbee.com

Sacramento area health officials are warning people and their pets to not swim in rivers, lakes and ponds with evidence of blue-green algae in the water after the death Monday of a dog that swam at Sand Cove Park Beach.

Dog owners reported seeing greenish water at the beach at the time the dog entered the Sacramento River, said John Rogers, Sacramento County environmental health division chief. Blue-green algae has already been implicated in at least three dog deaths in Sonoma and Mendocino counties in September, and incidents nationally have been rising. No human deaths in the state have been reported in connection with the algae.

“We’re advising the public to stay away from water with foam, scum or mats,” Rogers said.

Blue-green algae, known as cyanobacteria, is naturally found in fresh and marine water, but its presence becomes a health problem when large quantities collect, and when they’re seen as a bloom or surface scum.

Ingesting water with the algae can expose pets and humans to symptoms including eye irritation, gastrointestinal distress, muscle tremors and breathing difficulty. In large quantities, the toxins can also cause neurological or liver damage and lead to death. Reactions can occur anywhere from a few hours to days after exposure.

Depending on the dose, exposure can trigger very rapid mortality, said Robert Poppenga, a veterinary toxicologist at UC Davis.

“We’ve had cases where dogs have gone in the water and come out - and within 30 minutes developed classical signs, and die,” Poppenga said. “Often people take them to the veterinarian but the dog is dead at the time of presentation.”

Kim Nava at the Sacramento County animal shelter said personnel there were helping to warn animals owners, including of livestock, about water with blue-green algae.

The exact cause of Monday’s dog death has yet to be established, and necropsy results are due later in the week, Rogers said.

“For a dog owner, the blue-green algae may not be real obvious,” Rogers said. “Pet owners should wash their pets off with fresh water.”

The death prompted testing of the water from Sand Cove Beach on Wednesday for two toxins: anatoxin-a and microcystin The tests found no unsafe levels of either toxin, but still, in a first, the city of Sacramento is posting signs near eight city beaches and parks such as Tiscornia and Miller parks telling people to avoid water with blue-green algae.

Testing of the water for toxins is ongoing and expected to be more comprehensive than initial testing, said Rogers, who added that such an incident is rare for the area.

Rogers said he expects more blue-green algae events if the state’s four-year drought continues. That’s because droughts create more pockets of slow-moving warm water in rivers, a situation that triggers more algal blooms. The presence of nitrogen and phosphorous, which are chemicals common in areas with agricultural activity, also create favorable conditions for the algal blooms.

“If global warming has the impact that we expect, then yes, we can expect more of this,” said Rogers.

Between 1978 and 2008, only three harmful freshwater algal outbreaks were reported nationwide to the Centers for Disease Control and Prevention. Between 2009 and 2010, 11 outbreaks were reported.

“We have become more aware of this within the last 10 years, and it’s something we’re monitoring and we want to be out in front of to keep Californians safe,” said Steve Gonzalez, spokesman for California Department of Fish and Wildlife.

Edward Ortiz: 916-321-1071, @edwardortiz