About 700,000 eggs have been sent to the UK from potentially contaminated Dutch farms, up from an early estimate of 21,000, the food watchdog has said.
The Food Standards Agency (FSA) said this represented 0.007% of eggs eaten in the UK each year and that any risk to public health was “very unlikely”.
However, 13 products containing egg have been withdrawn from supermarkets.
Dutch police have now arrested two people suspected of using the insecticide fipronil.
The FSA said that in the UK, the Dutch eggs were not sold as fresh eggs but used in foods with many other ingredients – mostly sandwich fillings or other chilled foods.
It said traces of fipronil – which can be harmful to humans – were mixed with other eggs so chemical residues would be “highly diluted”.
The British Egg Industry Council said shell eggs on sale to consumers in the UK were not affected.
It said: “All major UK retailers stock British Lion shell eggs and tests have shown that there is no risk from British eggs.”
Supermarkets in Belgium, the Netherlands and Germany have withdrawn millions of eggs from sale.
Processed foods containing eggs, including sandwiches and salads, have been recalled from UK supermarkets including at Sainsbury’s, Morrisons, Waitrose and Asda.
Should I stop eating eggs?
By James Gallagher, health and science reporter, BBC News
Fipronil should not be allowed anywhere near food.
But the risk from eggs is thought to be low, because the number of contaminated eggs is also low.
While 700,000 eggs sounds like a lot, it is worth remembering we eat 34 million every single day in the UK.
It is why the Food Standards Agency says it is “very unlikely” there is any health risk.
Many of the affected eggs will have already passed through the food chain before anyone was aware of the scandal.
And the FSA has now pulled egg sandwiches and egg salads off the shelves that were made while contaminated eggs were still being imported.
It insisted there is “no need” for people to stop eating eggs.
Fipronil, which is used to kill lice and ticks on animals, can damage people’s kidneys, liver and thyroid glands if eaten in large quantities.
Heather Hancock, FSA chairwoman, said it was not “something to worry about” and that any health impact was unlikely.
“These aren’t eggs that are in people’s fridges in the UK, these are eggs that have gone into the food chain and the level of risk to public health is very low,” she told BBC Radio 4’s World at One programme.
The FSA initially thought far fewer eggs – 21,000 – had been distributed to the UK from implicated farms between March and June this year and last Monday believed affected products were no longer on shelves.
In an update on Thursday, the FSA said: “Some of the products made from these eggs will have had a short shelf life and will have already been consumed, however, we identified some that were still within the expiry date.”
It added: “While in some European countries eggs containing Fipronil residues have been sold as fresh eggs, in the UK this is not the case.”
Aldi and Lidl stores in Germany are among the supermarkets to remove eggs from their shelves, in a move Aldi described as “purely precautionary”. Eggs sold in its UK stores were British, Aldi said.
Withdrawn egg products
- Sainsbury’s ham and egg salad 240g – best before 9-14 August
- Sainsbury’s potato and egg salad 300g – 9-14 August
- Morrisons potato and egg salad 250g – 13 August
- Morrisons in-store cafe egg and cress sandwich – 11 August
- Morrisons in-store cafe sandwich selection – 11 August
- Waitrose free range egg mayonnaise 240g – 13 August
- Waitrose free range reduced fat egg mayonnaise – 170g – 14 August
- Waitrose free range egg and bacon – 170g – 14 August
- Waitrose free range egg and bacon – 170g – 16 August
- Waitrose free range egg mayonnaise – 240g – 16 August
- Asda baby potato and free range egg salad – 9-14 August
- Asda spinach and free range egg snack pot – 9-14 August
- Asda FTG ham and cheddar ploughman’s salad bowl – 9-13 Aug
Source: FSA (10 August)
It follows a joint investigation by Dutch and Belgian police of several premises thought to be using the substance, which can harm humans and is banned in food production.
The Netherlands is Europe’s biggest egg producer – and one of the largest exporters of eggs and egg products in the world.
The problem first surfaced earlier in August, when Aldi withdrew all its eggs from sale in Germany.
It has since emerged Belgian officials knew about the contamination in June, but did not make the information public.
More than 100 poultry farms have been closed during the investigation, and 26 suspects identified and evidence seized from their companies.
It is thought that fipronil was added to disinfectant used on some chicken farms.
The UK produces 85% of the eggs it consumes but imports almost two billion annually, the FSA said.