Japanese officials reported last week that melamine was found in dried whole processed eggs imported from China.

The Chinese seller later alerted the company in Tokyo that it had found melamine in its feed ration, prompting the investigation.

The company imported about 20 tons of product last month and sold the entire lot to a subsidiary of a major food company. About 400 kilos of the tainted product was then sold to a commercial bakery and used in making baked items that were sold to the public. No trace of melamine was found in any of the bakery’s products, however.

According to the USA Poultry & Egg Export Council, Japan imports nearly all of its dried egg products, and the U.S. is the major supplier. China is the third-leading supplier.

The trading company said it was aware of China’s melamine issue but did not account for possible contamination of eggs through the feed eaten by laying hens.