The public has been warned against against recreational gathering of shellfish such as mussels, clams, cockles or oysters over increased levels of illness-causing toxins.
Routine shellfish monitoring by the Marine Institute along South West and West coasts detected increased levels of these naturally occurring compounds in recent weeks.
Such levels are common at this time of the year and are due to microscopic phytoplankton species blooming in coastal waters during the warmer and longer days of summer, the institute says.
Toxins they produce can accumulate in filter feeding shellfish and can make people ill, even if the shellfish is cooked, it adds.
The specific toxins of concern may cause diarrheic shellfish poisoning (DSP), a temporary gastroenteritis-like illness, or the less common paralytic shellfish poisoning (PSP), which can result in serious illness.
Commercial shellfish businesses in affected areas have been closed temporary in the interest of public safety — though safe alternatives are available from other parts of the country through approved suppliers.
Dave Clarke is manager of the Marine Institute’s shellfish safety programme.
“In Ireland we operate a world class-shellfish safety programme to ensure food safety prior to harvesting,” he says.
“This sophisticated monitoring programme is designed to protect the consumer and ensure the highest quality of Irish shellfish on international and home markets.
“This summer, so far, has seen high levels of toxic phytoplankton and toxins in shellfish requiring temporary closures until the problem abates. It is stressed, however, that these only affect shellfish. Swimming and other coastal recreations are not affected.
“We would strongly advise the public to avoid picking their own shellfish along the shoreline, and to only source shellfish from an approved retail establishment.”