Eggs contaminated with a potentially harmful insecticide were imported from Europe and have been distributed throughout the United Kingdom and other countries, according to England’s Food Standards Agency (FSA). 
The number of eggs containing the insecticide fipronil, used in flea and tick products, is thought to be very small, thank goodness, but grocers in Germany, the Netherlands, Belgium, Sweden, and Switzerland have had to pull millions of eggs from store shelves as a precaution.
It is believed that fipronil was used on chickens in Belgium.
The FSA claims the risk to human health is extremely low.
The agency said:
“The number of eggs involved represents about 0.0001% of the eggs imported into the UK each year.
Our risk assessment, based on all the information available, indicates that as part of a normal healthy diet this low level of potential exposure is unlikely to be a risk to public health and there is no need for consumers to be concerned.”
The FSA said that based on the findings of its investigation so far, the affected eggs are no longer available for purchase.
The contamination was kept a secret for weeks and did not trigger the European Union’s (EU) international food safety alert system, allegedly due to a fraud investigation.
Belgium’s agriculture minister said he had ordered the country’s food safety agency to explain why it waited until July 20, 2017 to inform neighboring countries of the problem, when it was aware of the problem back in June.
A criminal investigation has been launched.
Food security expert, professor Chris Elliott, said:
“The report indicated that it (fipronil) should not be used in any food-producing animal of any description, so the Belgian authorities are following a line of investigation to say that there was illegal use… it was actually some serious fraud that was happening somewhere between Belgium and the Netherlands.
All of the information from the food safety authorities right across Europe is that consuming the eggs is not going to endanger anybody’s health.
I’m confident wherever you are in Europe or in the UK, enjoy your eggs.”
Fipronil is considered by the World Health Organization (WHO) to be moderately toxic to humans. The pesticide can damage the kidneys, liver, and lymph glands, and may cause symptoms such as nausea, vomiting, and eye irritation. 
The FSA said on its website:
“The government has already taken action to prevent any risk to UK consumers by adding fipronil to its robust surveillance program in UK farms.
We have no evidence that eggs laid in the UK are contaminated or that fipronil has been used inappropriately in the UK. Eighty-five per cent of the eggs we consume in the UK are laid here.”
Several million hens may need to be killed at 150 companies in Belgium, a Dutch farming company has said. About 300,000 have already been put down. 
 Sky News