Japan braces for potential radiation catastrophe

140,000 told to stay indoors; winds spread radioactivity over Pacific; Japan's stocks down 10%; Japanese PM slams plant's handling of crisis.

Japan Self-Defense Force officers (R) 311 (photo credit: REUTERS/KYODO Kyodo)
Japan Self-Defense Force officers (R) 311
(photo credit: REUTERS/KYODO Kyodo)
TOKYO - Japan faced a potential catastrophe on Tuesday after a quake-crippled nuclear power plant exploded and sent low levels of radiation floating towards Tokyo, prompting some people to flee the capital and others to stock up on essential supplies.
Prime Minister Naoto Kan urged people within 30 km (18 miles) of the facility north of Tokyo -- a population of 140,000 -- to remain indoors amid the world's most serious nuclear accident since the Chernobyl disaster in Ukraine in 1986.
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Around eighthours after the explosions, the UN weather agency said winds were dispersing radioactive material over the Pacific Ocean, away from Japan and other Asian countries. The Geneva-based World Meteorological Organization added that weather conditions could change.
Radiation levels in the city of Maebashi, 100 km (60 miles) north of Tokyo, and in Chiba prefecture, nearer the city, were up to 10 times normal levels, Kyodo news agency said. Only minute levels were found in the capital itself, which so far were "not a problem", city officials said.
Two of the reactors exploded on Tuesday at the Fukushima Daiichi plant after days of frantic efforts to cool them. Kyodo news agency said the nuclear fuel pool at the No. 4 reactor may be boiling, suggesting the crisis is far from over at the plant, 240 km (150 miles) north of Tokyo.
"The possibility of further radioactive leakage is heightening," a grim-faced Kan said in an address to the nation. "We are making every effort to prevent the leak from spreading. I know that people are very worried but I would like to ask you to act calmly."
Levels of 400 millisieverts per hour had been recorded near the No. 4 reactor, the government said. Exposure to over 100 millisieverts a year is a level which can lead to cancer, according to the World Nuclear Association. The government later said radiation levels around the complex had plunged.
The plant operator pulled out 750 workers, leaving just 50, and a 30-km no-fly zone was imposed around the reactors.
"Radioactive material will reach Tokyo but it is not harmful to human bodies because it will be dissipated by the time it gets to Tokyo," said Koji Yamazaki, professor at Hokkaido University graduate school of environmental science. "If the wind gets stronger, it means the material flies faster but it will be even more dispersed in the air."
Despite pleas for calm, residents rushed to shops in Tokyo to stock up on supplies. Don Quixote, a multi-storey, 24-hour general store in Roppongi district, sold out of radios, flashlights, candles and sleeping bags.
In a sign of regional fears about the risk of radiation, China said it would evacuate its citizens from areas worst affected but it had detected no abnormal radiation levels at home. Air China said it had cancelled flights to Tokyo.
Several embassies advised staff and citizens to leave affected areas. Tourists cut short vacations and multinational companies either urged staff to leave or said they were considering plans to move outside Tokyo
"What the hell is going on?"
Japanese media have became more critical of Kan's handling of the disaster and criticised the government and nuclear plant operator Tokyo Electric Power Co (TEPCO) for its failure to provide enough information on the incident.
Kan himself lambasted the operator for taking so long to inform his office about one of the blasts, demanding to know "what the hell is going on?", Kyodo reported.
Kyodo said Kan had ordered TEPCO not to pull employees out of the plant.
"The TV reported an explosion. But nothing was said to the premier's office for about an hour," a Kyodo reporter quoted Kan telling power company executives.
As concern about the crippling economic impact of the nuclear and earthquake disasters mounted, Japanese stocks fell as much as 14 percent before ending down 9.5 percent, compounding a slide of 7.5 percent the day before. The two-day fall has wiped some $620 billion off the market.
The full extent of the destruction from last Friday's 9.0-magnitude earthquake and tsunami that followed it was still becoming clear, as rescuers combed through the region north of Tokyo where officials say at least 10,000 people were killed.