JAPAN’S NUCLEAR AUTHORITIES have said radiation levels around the Fukushima I nuclear power plant have reached levels that can endanger human health.

The admission came after a third explosion in as many days at the Fukushima I plant, when reactor 2 was hit by an overnight blast – which, unlike the two that preceded it, is thought to have damaged the innermost protection surrounding the nuclear core.

A fire at reactor number 4, meanwhile, is thought to have further added to the radioactive emissions. The International Atomic Energy Agency said the fire had broken out in a storage pond for ‘spent’ fuel.

It added that the fire, which has since been extinguished, may have been caused by an internal hydrogen explosion.

Speaking to Japanese citizens within the last few hours, Japan’s chief government spokesman confirmed that the latest explosion, and the fire at reactor 4, had resulted in a release of radioactivity into the surrounding atmosphere.

Yukio Edano added that the level of radioactive emissions being recorded around the plant were not high enough to “impact human health”.

In a televised address, prime minister Naoto Kan urged the last residents living within a 20km exclusion zone to evacuate the area, and imposed a no-fly zone for 30km around the plant.

Plant operator TEPCO has now said that radiation levels for one hour’s exposure are up to eight times the safe annual dosage.

Japan’s meteorological agency has suggested that the level of wind over the last few days mean the areas around Tokyo may begin to record increased radioactive activity in the next day.

The news kicked off a flurry of chaos in the capital, with eyewitnesses reporting major panic at train stations while citizens attempt to evacuate the city and travel to the country’s west coast.

Japan had yesterday admitted that the nuclear cores of reactors 1, 2 and 3 were all probably melting, but the new fire at reactor 4 poses further questions as to the ongoing safety of the Fukushima I plant.

The economic impact of Japan’s ongoing disasters – kicked off by a 9.0-magnitude earthquake and tsunami last Friday – is continuing too; the Nikkei share index fell by 10.55 per cent in Tuesday’s trading.

The official death toll as a result of the disasters currently stands at 2,414.

What happens in a nuclear meltdown? >