Tests on rice from Onami district found it had elevated levels of radioactive caesium

This article is more than 8 years old

This article is more than 8 years old

The Japanese government has banned rice shipments from an area of Fukushima prefecture after tests revealed they contained levels of radioactive caesium that exceed safe limits.

It is the first time the government has banned shipments of rice since an earthquake and tsunami badly damaged the Fukushima Daiichi nuclear power plant on 11 March, sending three of its six reactors into meltdown in the worst accident of its kind since Chernobyl.

The rice, from the Onami district in the prefecture's north-east, was being prepared for sale but none had found its way on to the market, reports said.

Tests conducted this week showed that a batch of Onami rice harvested in the autumn contained up to 630 becquerels of caesium per kg, compared with the government's safe limit of 500 becquerels per kg.

The finding prompted the government to order the governor of Fukushima prefecture, Yuhei Sato, to halt all rice shipments from the area's 154 farms.

The chief cabinet secretary, Osamu Fujimura, said he had asked Sato to tighten monitoring of rice grown in the area. "If we confirm the safety of the grain in the region, we may consider lifting a ban on shipments," he said.

"The rice in question was caught before shipments. Not even a single grain from the patch is in circulation."

Sato said: "I can tell you that you don't have to worry at all about rice that has already been shipped." Last month, however, he had given assurances that rice from Fukushima was safe following tests on batches grown in 48 parts of the prefecture, including Onami, located about 40 miles (60km) from the plant.

Onami accounted for 1.8% of Fukushima's total rice crop and the radiation levels, while above the government's safety threshold, did not pose a risk to health, reports said.

But the discovery is certain to reignite concern over the safety of food from the Fukushima area and the authorities' ability to ensure tainted produce does not go on sale.

In July the government banned all shipments of beef from the prefecture after meat from more than 500 cows that had been fed contaminated straw was sent to other parts of the country.

Bans have been imposed on some vegetables and milk, and elevated levels of radiation have been found in green tea grown 250 miles from Fukushima Daiichi.

Supermarkets in Tokyo are divided over whether to accept rice from Fukushima. Some stores and wholesalers have taken advantage of the grain's comparatively low price but only five supermarket chains are selling it in the capital.

The radiation scare is unlikely to affect rice distribution in Japan. Fukushima prefecture produced almost 440,000 tonnes of rice last year – the fourth-largest source in the country – and the Onami district accounts for just 192 tonnes of the nationwide total.