Recent samples taken at East Loch Ollay, South Uist have indicated the presence of blue-green algae.
As a precautionary measure, notices have been posted next to the loch, warning that contact with the algal scum should be avoided.
Adjoining landowners and fishing interests have been advised of the situation as have the Environmental Health section of Comhairle nan Eilean Siar, SEPA Stornoway Office and NHS Western Isles.
Blue-green algae exist in fresh waters in Great Britain and throughout the world; they are noticed when their concentrations increase to form “blooms” and when they form scums – looking like blue-green paint.
Some blue-green algae may give rise to adverse medical effects – but not always.
The actions currently taken are precautionary.