Cornwall Council says it is putting up signs warning dog owners to be vigilant.
It follows reports of Hemlock roots washing up on beaches in the area, including Fistral and Little Fistral.
The council said in a statement that the plant, which is native to Cornwall, can be washed downstream from riverbanks during the winter, eventually ending up on beaches. Found in damp areas, its roots, leaves, and seeds contain a toxin that can cause severe seizures, respiratory failure, and death in animals if ingested. The roots also resemble parsnips in look and smell.
As a precaution, the council is urging owners to keep their dogs on leads following reports of dogs falling ill, with some cases proving fatal.
Radio Newquay understands that other beaches in the area may also be affected including Tolcarne and the Gannel.
In a statement on Tuesday, Newquay Town Council said it had received multiple reports of dogs becoming unwell after visiting the area and confirmed that Cornwall Council is aware of the situation. The town council has advised owners to avoid walking their dogs in the affected locations for now.
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