As radiation hits Tokyo, Japan tries to avert catastrophe

China evacuates citizens from some areas; Kan slams TEPCO's handling of nuclear plant disaster, warns "radioactive leakage heightening."

japan radiation_311 reuters (photo credit: KYODO Kyodo / Reuters)
japan radiation_311 reuters
(photo credit: KYODO Kyodo / Reuters)
TOKYO - Japan raced to avert a catastrophe on Wednesday after an explosion at a quake-crippled nuclear power plant sent radiation wafting into Tokyo, prompting some people to flee the capital and others to stock up on essential supplies.
The crisis escalated late on Tuesday when operators of the facility said one of two blasts had blown a hole in the building housing a reactor, which meant spent nuclear fuel was exposed to the atmosphere.

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Prime Minister Naoto Kan urged people within 30 km (18 miles) of the facility -- a population of 140,000 -- to remain indoors, as Japan grappled with the world's most serious nuclear accident since the Chernobyl disaster in Ukraine in 1986.
Officials in Tokyo -- 240 km (150 miles) to the south of the plant -- said radiation in the capital was 10 times normal at one point but was not a threat to human health in the sprawling high-tech city of 13 million people.
Toxicologist Lee Tin-lap at the Chinese University of Hong Kong said such a radiation level was not an immediate threat to people but the long-term consequences were unknown.
"You are still breathing this into your lungs, and there is passive absorption in the skin, eyes and mouth and we really do not know what long-term impact that would have," Lee told Reuters by telephone.
Around eight hours after the explosions, the UN weather agency said winds were dispersing radioactive material over the Pacific Ocean, away from Japan and other Asian countries.
Authorities have spent days desperately trying to prevent the water which is designed to cool the radioactive cores of the reactors from running dry, which would lead to overheating and the release of dangerous radioactive material into the atmosphere.
They said they may use helicopters to pour water on the most critical reactor, No. 4, within two or three days, but did not say why they would have to wait to do this.
"The possibility of further radioactive leakage is heightening," a grim-faced Kan said in an address to the nation earlier in the day.
"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."
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 some flights to Tokyo.
The US Navy said some arriving warships would deploy on the west coast of Japan's main Honshu island instead of heading to the east coast as planned because of "radiological and navigation hazards".
The risks of the US relief mission have been illustrated by the growing number of US personnel exposed to low-levels of radiation. Still, a Navy spokesman said exposure levels of returning crew were well within safety limits and that operations to assist close ally Japan would continue.
Kan slams TEPCO operator's handling of nuclear plant disaster
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 their 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, 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. "What the hell is going on?"
Yukiya Amano, director general of the International Atomic Energy Agency (IAEA), told a news conference there was a "possibility of core damage" at unit 2. The damage is estimated to be less than 5 percent of the fuel, he said.
He said there was also possible damage in the bottom part of the primary containment vessel, but that this was not confirmed.
"Is it a crack? Is it a hole? Is it nothing? That we don't know yet," Amano said. But he said the pressure in the primary containment vessel had not fallen. "If there is a huge damage the pressure should go down."