New Hampshire public health and environmental health officials are warning recreational users to avoid contact with the water in Lake Monomonac and some other water bodies due to harmful cyanobacteria algal blooms.
Tests of samples collected from 17th of July showed unacceptable levels of cyanobacteria or blue-green algae in the water bodies. The state threshold for cyanobacteria or blue-green algae is 70,000 cells/ milliliter.
Health officials identified cyanobacteria as Aphanocapsa, Anabaena and Woronichinia. The heaviest blooms were found close to the shorelines.
Cyanobacteria are not rare, but excess phosphorus is available to the water leads to blooms and surface scums. Places in New Hampshire that have got contaminated with cyanobacteria this summer include Long Pond in Pelham and Elm Brook Park Beach in Hopkinton.
A person exposed to cyanobacteria can experience a range of health problems from skin irritation to liver damage.