German discount supermarket giant Aldi said Friday it was pulling all the eggs from its shelves in the country over an insecticide scandal stemming from the Netherlands.
The chain said it was making the move "purely as a precaution" but acknowledged it could lead to "market shortages" for eggs in Europe's top economy as the impact of the affair widened.
Aldi had already pulled all of the Dutch eggs from its stores earlier in the week, as it emerged that at least three million eggs tainted with a toxic insecticide had made their way to Germany and been sold.
However a regional agriculture minister, Christian Meyer of Lower Saxony, told ZDF public television Friday that it was now believed 10 million contaminated eggs might have reached Germany.
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.
Dutch and Belgian media reports that the substance containing the insecticide was supplied to Chickfriend by a Belgian firm have not been confirmed.
In large quantities, the insecticide is considered to be "moderately hazardous" according to the World Health Organisation, and can have dangerous effects on people's kidneys, liver and thyroid glands.
With losses expected to run into millions of euros (dollars), it is another blow for Dutch poultry farmers after 190,000 ducks were culled in November amid a highly infectious strain of bird flu.
Marieke van der Molen, spokeswoman for the Dutch public prosecutor's office, said a criminal investigation had been opened to determine the source of the contamination.
Belgium's federal food chain security agency (AFSCA) has also launched a criminal probe in cooperation with prosecutors.