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Algae information

This information is provided by the Division of Environmental Toxicology, Hazard Assessment and Prevention (TOX) within the Department of Public Health.
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Guidelines

Guidelines for Cyanobacteria at Recreational Freshwater Locations
Open PDF file, 1.43 MB,  Guidance for Local Health on Responding to CyanoHABs (English, PDF 1.43 MB)
Open DOCX file, 4.99 MB,  Guidance for Local Health on Responding to CyanoHABs (English, DOCX 4.99 MB)

Fact Sheets

Climate change and contact with cyanobacteria
Harmful algae blooms in freshwater bodies
Microcystis and Anabaena fact sheet
Red tide fact sheet

Find out information about red tide. The printer-friendly and Spanish versions of this fact sheet can also be downloaded.

Educational materials

Identifying cyanobacterial blooms and scums (photographs of blooms and scums)
Preventing animal illnesses caused by harmful algae blooms

Presentations

Open PPTX file, 1.04 MB,  Recreational Risk Management of Surface Waterbodies: Cyanobacteria Surveillance in Massachusetts (English, PPTX 1.04 MB)
Open DOCX file, 80.35 KB,  Recreational Risk Management of Surface Waterbodies: Cyanobacteria Surveillance in Massachusetts (English, DOCX 80.35 KB)

Related links

CDC's Harmful Algal Bloom (HAB) information

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