The beach and swimming area at Christie Lake Conservation Area has been closed to swimmers and animals, the Hamilton Conservation Authority said in a news release on Friday.
Water samples taken from several spots along the shoreline showed the presence of blue-green algae, confirmed Hamilton Public Health Services.
The naturally occurring algae, known as cyanobacteria, can produce toxins known as microcystins, which are a health risk to humans and animals. It typically forms in shallow, warm and stagnant or slow moving water.
Skin contact with or accidental ingestion of the algae can lead to a number of symptoms including a rash or other skin irritation, red eyes, swollen lips, sore throat, fever, nausea, vomiting and diarrhea.
The Hamilton Conservation Authority says the most serious