In its latest update on the fipronil contamination scandal, which has seen eggs from the Netherlands, Belgium and Germany withdrawn from sale in France, Germany, Switzerland, Sweden and other European countries, the Food Standards Agency (FSA) has admitted that “more eggs from affected farms than previously identified came to the UK.”

Having said at the beginning of the week that only a small number (around 21,000) of tainted eggs had entered the country, in response to a tip-off from German authorities, the UK FSA admitted on Thursday that the number of contaminated eggs to have reached Britain is closer to 700,000.

Fipronil is commonly used as an active ingredient in flea and tic treatments, but it is illegal to use the pesticide on crops or food producing animals. The current food safety scandal originated in the Netherlands, where authorities say over 150 farms have been implicated. The exact cause of contamination was not immediately clear; Germany’s agriculture ministry said its own investigations linked contamination on German and Belgian farms to a Dutch cleaning company, whilst Dutch farm unions blamed a specific product, used to suppress blood mites in chickens.

Earlier in August, the Dutch government released the batch codes of eggs known to be contaminated with fipronil, and revealed that one batch constituted a serious threat to public health.

Following its own investigation, FSA announced on Thursday that fipronil-tainted eggs are not thought to pose a significant health threat in the Britain. The extra eggs have been used in processed foods, mostly sandwich fillings or other chilled foods, where they have been mixed with unaffected eggs from other locations. Products containing the eggs that haven’t already been bought and consumed are being withdrawn from sale, FSA said.

In its update, the UK Agency noted, “85% of the eggs we consume in the UK are laid here. We have 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 underway across the UK and results to date for England and Wales show no exposure to Fipronil.”  

Heather Hancock, Chair of the Food Standards Agency, commented, “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.”

In the Netherlands, where a criminal investigation has been launched in response to the scare, authorities have detained two men in connection with illegal use of pesticides on poultry farms. Dutch prosecutors said announced that the directors of a company thought to have used products containing fipronil on poultry farms were detained during a series of raids.

The raids were carried out in conjunction with Belgian authorities, who revealed last week that they had known about tainted eggs since June this year, but had not raised the alarm to avoid jeopardising an ongoing fraud investigation, and to allow time to assess the scale of the contamination.