Blue-green algae has been detected in Wickapogue Pond in Southampton, Suffolk County announced in an advisory Friday.
Health officials are asking residents not to use, swim or wade in these waters and to keep their pets and children away from the area.
Blue-green algae are naturally present in lakes and streams in low numbers, officials said. They can, however, form blooms in shades of green, blue-green, yellow, brown or red.
The algae in abundance may produce “floating scums” on the surface of the water, giving it a paint-like appearance.
County officials said the public should avoid contact with “scummy” or discolored water and that if contact does occur, residents should rinse themselves with clean water immediately.
Those who experience nausea, vomiting, diarrhea, skin, eye or throat irritation, allergic reactions or breathing difficulties should seek medical help, the county advised.
The algae was detected through water sampling by SUNY Stony Brook.
Residents wishing to report a suspected blue-green algae bloom at a body of water that contains a Suffolk County-permitted bathing beach should contact the Suffolk County Department of Health Services’ Office of Ecology at 631-852-5760.
For those bodies of water that do not include Suffolk bathing beaches, residents should call the Division of Water at the New York State Department of Environmental Conservation at 518- 402-8179.