The Department of Agriculture and Food said last night that over 600 tonnes of contaminated animal feed ingredient, which contained an excess level of hydrocyanic acid, had already been incorporated into animal feed.
The contaminated linseed cake arrived in the Netherlands earlier this year in a 7,000-tonne consignment of animal feed ingredients from the US.
A portion of that shipment, 3,270 tonnes, arrived in Ireland in the past week, shortly before the Netherlands authorities found that the consignment contained a level of hydrocyanic acid (HNC) in excess of the maximum permitted level.
According to a Department statement last night, the Dutch authorities conveyed the results of their sampling through the European Rapid Alert System to the Food Safety Authority of Ireland.
Department officials held approximately 80 per cent of the consignment at a Dublin warehouse but the remainder, 650 tonnes, had already been used in the manufacture of animal feed.
A spokesman for the Department said it was testing the linseed cake itself, and having consulted with the Food Safety Authority, it was satisfied that the levels of HCN in the compound posed no risk to animal or human health.
Hydrocyanic acid, he said, was a natural organic compound found in many plants including linseed.
It could have an adverse effect on animal health if consumed at high levels although it does not affect people who eat the products from these animals, he said.
"We are continuing to monitor and evaluate the situation and we are carrying out tests to ensure there is no danger to animals or humans.
"It is possible that we may release the remainder of the consignment when all the tests are completed," he said.