Boston’s Jamaica Pond will be closed until a harmful algae bloom in the water is over, according to health officials.
The pond was closed Friday for water activities including swimming, fishing, and letting pets play in the water, due to the blue-green algae, also known as cyanobacteria, according to a statement from the Boston Public Health Commission.
The harmful algae blooms “usually last for 1-3 weeks depending on weather, but when it looks like it’s over, Boston Parks [and Recreation] works with the [Department of Public Health] Bureau of Climate and Environmental Health for the test results,” Pai En Yu, the communications director for the Boston Public Health Commission, said in an e-mail to the Globe.
Swallowing small amounts of cyanobacteria can cause gastrointestinal symptoms, and swallowing large amounts can cause liver or neurological damage, according to the Massachusetts Department of Public Health.
Cyanobacteria can also cause skin or eye irritation if touched, and asthma-like symptoms if water spray is inhaled, according to the department. Dogs can become ill and die from licking cyanobacteria off their fur, it said.
Any people or pets who accidentally touch the affected pond water should rinse off immediately, and if either a person or pet swallows the water, a doctor or veterinarian should be contacted, the department said.
Two of the most common factors of a cyanobacteria bloom are the presence of phosphorus and nitrogen, which are found in fertilizers and human and animal waste, according to the department. Warm weather, sunlight, excess nutrients, and stagnant or slow-moving waters help cyanobacteria grow faster, the department said.
Residents should avoid contact with the pond until the water is tested and officials announce that the harmful algae bloom is over, according to the Boston Public Health Commission.
Bailey Allen can be reached at bailey.allen@globe.com. Follow her on Twitter @baileyaallen.