Fife Council has urged members of the public to stay out of the water at Lochore Meadows after huge amounts of algae was discovered.
The loch in central Fife is a popular place for paddle boarding, wild swimming, and fishing, but those visiting at the weekend were met with a warning notice about the plant that can make people "severely" sick. High concentrations of blue-green algae have been found in the water and Fife council have advised people and their animals to keep out temporarily.
Swallowing the water or having contact with algal scum can cause harmful effects such as rashes, vomiting, diarrhoea, muscle or joint pain. The bacteria that contains dangerous toxins potentially fatal to pets, livestock and birds if ingested even in small quantities.
As the health risks for consuming fish from the loch are unknown, the council have also advised that it would sensible not to eat fish caught in the waters.
The protective service at Fife Council posted the warning notice last Friday, and it will be effective until next Friday, July 8.
Sightings of algal bloom in lakes, ponds or rivers has been spotted in around 50 locations across the UK by the UK Centre for Ecology and Hydrology's (UKCEH). In late April, a Cocker Spaniel puppy died of suspected blue green algae poisoning after a swim in Anton Lakes, Hampshire.
Blue green algae multiplies in warm weather, making summer a dangerous time for a dip.
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