Radioactivity in groundwater below a stricken nuclear power station in north-eastern Japan measured 10,000 times the legal threshold, news reports said Friday, citing a plant operator, dpa reported.
The contaminated groundwater was detected from around the turbine building of reactor number 1 at the Fukushima Daiichi Nuclear Power Plant, which was crippled by the March 11 earthquake and ensuing tsunami, said Tokyo Electric Power Co (TEPCO), the operator of the station.
The Health Ministry reported Thursday that beef in Fukushima contained radioactive material above the legal limit, the first such detection in beef.
The ministry found 510 becquerels of radioactive cesium in beef from Tenei Village, which is above the 500-becquerel legal limit.
The village is located 70 kilometres from the plant.
On Wednesday, the International Atomic Energy Agency (IAEA) suggested Japan consider evacuating Iitate village, about 40 kilometres from the plant, after the agency found levels of radioactive iodine in the soil there that exceeded its health limits.
The village is not only outside the 20-kilometre evacuation zone around the plant but also beyond the 30-kilometre zone in which people have been advised to stay indoors.
In the soil contamination in Iitate, IAEA experts found radioactivity from iodine-131 at 25 megabecquerels per square metre of soil, more than double the agency's evacuation threshold of 10 megabecquerel, an unnamed IAEA source said.
"The first assessment indicates that one of the IAEA operational criteria for evacuation is exceeded," IAEA senior official Denis Flory told reporters.
The Japanese government said Thursday that it had no immediate plans to expand the evacuation zone despite the recommendation by the global nuclear watchdog.
Chief Cabinet Secretary Yukio Edano said Tokyo would instead reinforce radiation monitoring of soil.
Further contamination of seawater was reported Thursday. The Japanese government's Nuclear and Industrial Safety Agency said that radioactive iodine at 4,385 times the legal limit was found in a seawater sample taken near the plant on the previous day.
Hidehiko Nishiyama, an agency spokesman, said the radiation- contaminated water posed no immediate threat to human health.
TEPCO was trying to clear contaminated water in some of the reactors' turbine buildings at the plant and tunnel-like trenches linked to them.
The operator doused overheating reactors and spent fuel pools with enormous amounts of water to cool them down, as damage to fuel rods from the heat could result in the release of massive amounts of radioactive material into the air.