Sources of Exposure & Risk Factors | Harmful Algal Blooms | CDC

Sources of Exposure & Risk Factors | Harmful Algal Blooms | CDC

Sources of Exposure & Risk Factors

Routes of Exposure

Boating in a lake with a HAB. Credit: Photo courtesy of Andy Reich.

A harmful algal bloom (HAB) can occur in water bodies around the world and can affect those who use these water bodies for recreation, agricultural, or drinking 1-4. People can be exposed to a HAB or HAB toxins when they swim, wade, or play in or near contaminated water; eat contaminated fish or shellfish; or use contaminated drinking water. The severity of illness and symptoms can vary depending on the type of exposure and the type of HAB toxin.

The main routes of exposure to HAB toxins are 5:

• Skin contact (through activities like swimming)
• Inhalation (by breathing in tiny airborne droplets or mist contaminated with HAB toxins)
• Ingestion (by eating or drinking food or water contaminated with HAB toxins)

Skin Contact expanded

Anyone who visits a contaminated water body during a HAB event can be exposed through direct contact with the contaminated water. Skin irritation and reactions in humans and animals can vary depending on the length of contact with the contaminated water and the type of HAB toxin present in the water 1,2.

References

1. Koreivienė J, Anne O, Kasperovičienė J, Burškytė V. Cyanotoxin management and human health risk mitigation in recreational waters.Environ Monit Assess. 2014;186(7):4443-59.
2. Van Dolah FM. Marine algal toxins: origins, health effects, and their increased occurrence. Environ health Perspect. 2000;108(Suppl 1):133.

Inhalation collapsed

Ingestion collapsed

References

1. Lopez CB, Jewett, EB, Dortch Q, Walton BT, Hudnell HK. Scientific assessment of freshwater harmful algal blooms.[PDF - 78 pages]Interagency Working Group on Harmful Algal Blooms, Hypoxia, and Human Health of the Joint Subcommittee on Ocean Science and Technology. Washington, DC. 2008.
2. Chorus I, Bartram J, eds. Toxic Cyanobacteria in Water: A guide to their public health consequences, monitoring and management.[PDF - 400 pages] London, United Kingdom: World Health Organization; Routledge, London; 1999.
3. Lopez CB, Dortch Q, Jewett EB, Garrison D. Scientific assessment of marine harmful algal blooms.[PDF - 72 pages] Interagency Working Group on Harmful Algal Blooms, Hypoxia, and Human Health of the Joint Subcommittee on Ocean Science and Technology. Washington, DC. 2008.
4. Anderson DM. Approaches to monitoring, control and management of harmful algal blooms (HABs). Ocean and Coastal Manag. 2009;52(7):342-347
5. Koreivienė J, Anne O, Kasperovičienė J, Burškytė V. Cyanotoxin management and human health risk mitigation in recreational waters. Environ Monit Assess, 2014;186(7):4443-59.