Swimmers have been warned to stay out of the sea at South Strand beach, Skerries in north Dublin, due to elevated levels of bacteria in the water.
Fingal County Council has issued the bathing ban for the popular beach during the hottest week of the year, after tests found E.coli levels were "higher than the acceptable limit".
The likely cause of the faeces-borne bacteria was “the impact of animal and birds as well as contamination of urban surface waters” the council said.
The advice not to swim was issued on Tuesday, initially for a 72 hour period, with further tests due to be conducted on Wednesday.
“Higher levels of bacteria are usually short-lived and most bathers are unlikely to experience any illness,” the council said.
The council has not closed the beach but “beach users are asked to respect the advisory notice as it has been put in place to ensure that the health of bathers is not compromised” it said.
In particular, it said, people should avoid swallowing or splashing water, wash their hands before handling food, avoid swimming with an open cut or wound, and void swimming if pregnant or have a weakened immune system.
