Very large quantities can cause damage to the kidneys, liver and lymph glands.
Commission spokeswoman Anna-Kaisa Itkonen said the aim was "to share the information so that everybody knows that it's now also up to the Swedish, Swiss, French and to the United Kingdom national authorities to check".
Belgium's agriculture minister meanwhile said he had ordered the country's food safety agency to report by Tuesday on why it failed to notify neighbouring countries until July 20 despite knowing about fipronil contamination since June.
Eggs contaminated with the insecticide fipronil were distributed in the United Kingdom after all, it has emerged - despite government assurances last week that the United Kingdom was not affected by the egg contamination scandal that is now rocking Europe.
Belgium meanwhile vowed full transparency about why it kept the scandal secret despite originally learning in June about the problem involving fipronil, a substance potentially risky to humans.
It is thought disinfectant used in products on chicken farms is to blame for a scare that has seen millions of eggs taken off shelves in Germany and the Netherlands and also implicated Belgian farms.
In the dark and silent shed of a small Dutch poultry farm, 1.8 million eggs closely packed together wait to be destroyed.
Unilever also said its products were not affected by the recall and remained "safe for sale and consumption".
An LTO spokesman said late Sunday that they "had to be eliminated because of contamination".
It said that the number of eggs involved represents about 0.0001 per cent of the eggs imported into the United Kingdom each year.
European Commission spokeswoman Anna-Kaisa Itkonen today said that the Netherlands, Belgium and Germany warned other member states through the EU's art system that the may have exported contaminated eggs in August.
Germany has demanded an explanation from Belgium about why the issue was kept covered up.
The authorities suspect the substance, fipronil, was introduced to poultry farms by a Dutch business named Chickfriend that was brought in to treat red lice, a nasty parasite in chickens.
It is thought to have been used on chickens in Belgium and could be potentially unsafe to humans.