Cyanobacteria blooms are potentially toxic to domestic animals,
livestock, wildlife, and humans due to the cyanotoxins produced. The
type and amount of toxin produced varies over time and from lake to
lake. Cyanotoxins can cause both acute and chronic illnesses that can
target the skin, liver, kidney, and central nervous system. Acute
effects, such as skin and mucous membrane irritations, can occur after
short-term exposure with water containing cyanotoxins. Chronic effects,
such as liver, kidney, and central nervous system damage, can occur over
a long period of time from ingesting water containing toxins. For more
information on cyanobacteria and the program, see our
Frequently
Asked Questions.
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Follow these steps to minimize immediate risks:
Check the
Healthy
Swimming Mapper prior to recreation.
Always perform a visual risk assessment looking for discoloration or
unusual growth.
- Report suspected blooms not already on the Healthy Swimming Mapper
through the Bloom
Report Form.
If a Warning is posted or the water looks suspicious:
- Do not wade, swim or drink the water.
- Keep pets and livestock out of the water.
- Wash with fresh water and soap if you’ve come into contact with
suspected cyanobacteria.
When in doubt, stay out!
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Examples of Cyanobacteria Blooms in New
Hampshire.
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