The Scottish Environment Protection Agency (Sepa) advice came as figures reported by The Ferret news website showed more than half of Scotland’s most popular beaches were contaminated with sewage in breach of safety limits this summer.

A total of 49 of 87 designated bathing waters recorded levels of faecal bacteria since May that could endanger health.

The Ferret said heavy rain had caused public sewers to flood and washed animal faeces off the land, resulting in water concentrations of bacteria that could cause stomach, ear, nose and throat infections.