Japan has resumed importing corn from the United States following a U.S. pledge to screen its shipments for the genetically modified StarLink grain, the U.S. Department of Agriculture said Tuesday.

The first shipment involves 127,000 tons of U.S. corn, the USDA said.

Japan suspended purchases of U.S.-grown corn last month after a Japanese consumer group found traces of StarLink corn in food products sold in supermarkets.

StarLink corn, made by the Franco-German company Adventis, has the potential to produce allergic reactions in humans and is only approved as animal feed in the U.S. Others say its long-term effects are still not known.

On Tuesday in Tokyo, the Health and Welfare Ministry said the USDA would screen corn shipments destined for human consumption to ensure they do not contain StarLink.

The health ministry confirmed Tuesday that about 380,000 tons of corn containing StarLink were imported in February from the U.S. It was the first time the government acknowledged the controversial grain had entered Japan. The ministry said that some 12 tons of corn flour also believed to contain StarLink were imported in August, of which 4 tons have already been sold or remain on store shelves.

The Agriculture, Forestry and Fisheries Ministry has asked the U.S. government to check shipments for corn used as animal feed as well.

Adventis said StarLink does not have adverse effects on humans, but Japan has banned StarLink corn entirely, while the U.S. allows it to be used for animal consumption.

In the U.S., StarLink corn caused a manufacturing shutdown after traces were found in taco shells in September.

Japan is the largest market for U.S. corn, purchasing about 15 million tons a year.