BRUSSELS (Reuters) – The European Union’s food safety watchdog urged member states on Thursday to monitor poultry products for the insecticide fipronil following the withdrawal of millions of chicken eggs from supermarket shelves last year.

The Parma-based EFSA tested some 5,500 samples of eggs and chicken meat between Sept. 1 and Nov. 30 of last year and found that about one in seven contained levels of fipronil exceeding the legal limit.

“It is recommended that fipronil and other acaricides be included in the future monitoring activities of the member states,” EFSA said in a report.

Eight countries had submitted samples with elevated fipronil concentrations, including Italy, Germany and France, EFSA said.

Fipronil is commonly used to treat pets for fleas and ticks but is banned from use in the food chain because it may cause organ damage in humans if large quantities are ingested.

After a fipronil scandal broke last summer, Dutch authorities identified the source as a small supplier of cleaning products that had sold them to unwitting producers as a more efficient way to fend off red mites in poultry stables.

(Reporting by Robert-Jan Bartunek; Editing by Mark Heinrich)