Aug. 10 (UPI) -- Britain's Food Standards Agency on Thursday said about 700,000 eggs likely contaminated with the pesticide Fipronil entered the country and have probably already been eaten -- far more than officials previously thought.
The eggs came from farms in the Netherlands and were used as one ingredient in processed foods, such as sandwich fillings. The FSA initially estimated 21,000 contaminated eggs entered Britain.
The eggs in question represent 0.007 percent of eggs consumed in Britain every year, the FSA said -- adding that "it is very unlikely that there is any risk to public health from consuming these foods."
Any potentially-contaminated eggs or egg products still on store shelves are being withdrawn, officials said.
"We have now established that more eggs from affected farms than previously identified came to the U.K. It is very unlikely that these eggs pose a risk to public health, but as Fipronil is unauthorized for use in food-producing animals we have acted with urgency to ensure that consumers are protected," the FSA said in a statement Friday. "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 [expiration] date."
The FSA said the decision to withdraw the egg products is not due to food safety concerns, but rather because Fipronil is not authorized for use in food-producing animals. The products affected in Britain have low doses of Fipronil, decreasing their toxicity.
Millions of eggs have been destroyed so far due to Fipronil contamination.
Investigators believe the tainted eggs originated in the Netherlands -- Europe's largest egg producer, where about 10 billion are produced per year. Fipronil is used to help ward off ticks and lice in poultry, but is banned for use on animals meant for human consumption. Consumption of Fipronil in high doses over time can cause liver and kidney damage.
More than 180 Dutch chicken farms were closed amid follow-up examinations.
In at least one batch of the eggs tested in Germany, the Fipronil level was high enough that it could have caused illness in children, according to a German agriculture official.
Eric DuVall contributed to this report.