Dutch investigators have detained two men suspected of being involved in the illegal use of a pesticide at poultry farms that sparked a massive food safety scare in several countries.

The two men detained during a series of raids are directors of a company that allegedly used Fipronil on egg farms, Dutch prosecutors said in a statement.

Though no-one has been reported as falling sick, prosecutors said there is evidence that public health has been threatened by “the delivery or application of the biocide Fipronil in poultry houses in the egg sector”.

The raids in the Netherlands were carried out as part of a joint action with Belgian authorities.

Millions of eggs have been pulled from supermarket shelves in Germany, as well as Belgium and the Netherlands.

Around 700,000 eggs from Dutch farms implicated in a contamination scare have been distributed to Britain, rather than the 21,000 first estimated, the Food Standards Agency (FSA) has said.

The FSA said investigations into the Fipronil incident in Europe suggested it was “very unlikely” that the eggs posed a risk to public health, and products affected in the UK were processed foods in which egg is one ingredient among many others, mostly used in sandwich fillings or other chilled foods.

Millions of eggs have been taken off supermarket shelves
Millions of eggs have been taken off supermarket shelves (Lewis Whyld/PA)

It said some of the products made from these eggs will have had a short shelf life and will have already been consumed, but some were still within the expiry date and were being withdrawn by the businesses involved.

Many of the eggs were mixed with others which had not come from affected farms so Fipronil residues would be highly diluted, the FSA said.

The decision to withdraw the products was not due to food safety concerns but based on the fact that the pesticide is not authorised for use in food-producing animals.

The FSA said it had no evidence that eggs laid in the UK are contaminated or that Fipronil has been used inappropriately in the UK.

Testing of eggs on farms is under way across the UK and results to date for England and Wales show no exposure to Fipronil.

FSA chairwoman Heather Hancock said: “I’m confident that acting quickly is the right thing to do.

“The number of eggs involved is small in proportion to the number of eggs we eat, and it is very unlikely that there is a risk to public health.

“Based on the available evidence there is no need for people to change the way they consume or cook eggs. However, Fipronil is not legally allowed for use near food-producing animals and it shouldn’t be there.”