BEIJING // The sale of some food products has been stopped in Japan after traces of radioactivity thought to be from the crisis-hit Fukushima nuclear power plant were found.
Milk from a town in the same district as the plant and spinach from Ibaraki prefecture further south were removed from sale after testing positive for radioactive iodine.
In another scare, water samples from Tokyo and several districts of central Japan also contained abnormally high levels of radioactive iodine, although officials insisted levels were not high enough to damage health. Some samples also had higher levels of radioactive caesium.
The International Atomic Energy Agency (IAEA) reported yesterday evening that Japan's ministry of health, labour and welfare was considering halting the sale of all food products from Fukushima prefecture.
Radioactive iodine can be absorbed into the thyroid gland and cause damage, with children and young adults most at risk.
"Though radioactive iodine has a short half-life of about eight days and decays naturally within a matter of weeks, there is a short-term risk to human health if radioactive iodine in food is absorbed into the human body," an IAEA statement said. The Japanese authorities this week made nearly a quarter of a million units of iodine available to those fleeing the 20km exclusion zone surrounding the plant. Taking iodine supplements can prevent the body absorbing the substance in its radioactive form.
The news that radioactivity has been found in food is likely to cause much anxiety if reactions in other countries are anything to go by.
This week China was hit by panic buying of salt, as some consumers feared that in future batches could be contaminated with radioactivity. Some also bought salt in the mistaken belief that the iodine added to it could protect against radiation.
Engineers yesterday continued efforts to stabilise the Fukushima plant, more than a week after a 9.0-magnitude earthquake and tsunami disabled water pumps that cooled reactors.
Japan's chief cabinet secretary, Yukio Edano, gave grounds for optimism when he indicated temperatures at some reactors appeared to be under control.
"The situation there is stabilising somewhat," he said.
The crisis has been rated five on a seven-point scale for nuclear incidents by the Japanese authorities and isd be a major step towards keeping temperatures under control and preventing the meltdown of fuel rods. If meltdown took place, much larger amounts of radioactivity would be released.
In a statement yesterday, the IAEA said the plant had caused "elevated" radiation levels, but added these did not threaten public health outside exclusion zones.
"Dose rates in Tokyo and other areas outside the 30km zone remain far from levels which would require any protective action. In other words they are not dangerous to human health," the statement said.
The plant is surrounded by a 20km evacuation zone, and those living between 20km and 30km are advised to stay indoors and shut windows.
The death toll from the earthquake and tsunami rose to 7,348 yesterday, with a further 10,947 missing.
Construction of prefabricated houses for those who have lost their homes began yesterday in Iwate prefecture in the far north of Honshu island, although some work was delayed because low fuel supplies made it difficult to bring in building materials. In total, Iwate plans to build 8,800 houses for survivors who have lost their homes.
Survivors in Miyagi prefecture further south were urged by the district's governor to move to other parts of the island that could accommodate them. Some prefectures have said they could provide public housing for evacuees.
In another sign relief efforts were progressing, the port of Shiogama in Miyagi prefecture partially reopened yesterday, allowing a military vessel with food, bathtubs and heating oil to dock.
Nevertheless, many of the 390,000 forced to live in shelters since the earthquake and tsunami continue to face uncomfortable conditions in the cold weather.
A 6.1-magnitude aftershock was recorded yesterday close to the Fukushima nuclear plant, although there were no reports of injuries and no tsunami warning was issued.