Chinese retailers are pulling certain eggs off their shelves, after Hong Kong authorities found excessive levels of melamine in eggs from mainland China.
Authorities in China's northeastern city of Dalian banned the Hanwei Group from exporting its eggs Wednesday, and ordered a recall of all eggs already on the market.
They took action after Hong Kong authorities discovered high levels of melamine in eggs from Hanwei and another company (Jingshan Pengchang Agricultural Product Company) based in central Hubei province.
Chinese authorities say the industrial chemical may have been added to chicken feed.
The egg scandal raises further concerns about China's food safety, after Chinese-made milk products tainted with melamine killed four Chinese babies and sickened tens of thousands more.
Melamine can give food the appearance of higher protein levels. If consumed in high doses, it can cause kidney stones and kidney failure.
China has arrested 42 people in the tainted milk scandal.