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Exposure to CyanoHABs

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How are People are Exposed to Cyanobacteria and Cyanotoxins

The most common exposures to cyanobacteria and their toxins are those that occur during swimming or participating in other recreational activities in and on the water. These exposures include:

  • Oral exposure from accidental or deliberate ingestion of contaminated water;
  • Dermal exposure by direct contact of exposed parts of the body to water containing cyanobacteria cells. Also, cyanobacteria cells can accumulate in bathing suits, particularly diving suits, breaking and exposing skin to toxins, and;
  • Inhalation exposure through the aspiration of water containing cyanobacteria cells and their toxins.

Other major routes of human exposure are through ingestion of cyanotoxin-contaminated drinking water, inhalation while showering, dietary intake via consumption of cyanotoxins in contaminated foods and algal dietary supplements, and exposure from water used in medical treatments (e.g., medical dialysis). Consumption of mussels and clams collected during cyanobacterial blooms or immediately after blooms should be avoided.

Wind-driven currents may cause buoyant cyanobacterial blooms to amass on shorelines. These accumulations of cyanobacteria cells are much larger than blooms in open waters, thus presenting a greater risk to human and animal health.

How Animals are Exposed to Cyanobacteria and Cyanotoxins

Pets and other animals can be exposed to cyanobacteria and their toxins through drinking toxin-contaminated water or by swimming in waters with a cyanoHAB.  Animals can also be exposed by eating HABs mats or by licking cyanobacteria or toxins off their fur or hair.  As with humans, animals can also be exposed to HABs by direct contact of body parts when playing with contaminated water.

If you suspect a HAB is present, don't let your pet drink the water, play or eat scum mats, or swim in the water body.  Also, don't let your pet lick their fur after swimming in contaminated water.  If your pet has come into contact with water with a HAB, rinse them with tap water as soon as possible.  Seek veterinary care immediately if your pet has consumed or licked scum on its fur after swimming or playing in water that has a HAB.