The level of radiation near the site of the Japanese nuclear power plant in Fukushima, badly damaged by the earthquake last Friday, is increased considerably and the population within a radius of 30 km from the plant must remain in their homes.
It was announced by Japanese Prime Minister, Naoto Kan.
The approximately 200 thousand residents within 20 km from the plant were evacuated.
A fire broke out in the reactor no. 4 of the plant, that was shut down for maintenance work and so far it had no problems reported.
The fire was sent off by technicians from the armed forces U.S..
As in the case of reactors one and three, the fire was caused by hydrogen – slightly radioactive, released by the heat generated from nuclear fuel.
Edano explained that the level of radiation is currently 30 millisievert between reactors number two and three, 400 millisievert near reactor number three and 100 close to the reactor four.
A single dose of 1,000 millisievert (equale to a sievert, which is the unit of measurement of radioactivity), can cause temporary nausea and vomiting, one of 5,000 millisievert can kill within a month, about half of those who ‘s have received.
Abnormal levels of radioactivity were also recorded in Tokyo, but Saira Koga stated that these are not considered to be harmful to human body.
Municipal sources have reported that a level of 0,809 microsievert were detected in the morning in the city: so an amount of radiation higher than normal but not particularly high, though still twenty times higher than that which was recorded the day before.
To understand better, consider that a normal chest X-ray usually leads to a dose of 20 microsievert.
Level of radioactivity ten times higher than normal were recorded in Maebashi, a town about 100 kilometers north of Tokyo, and then closer to the central area of Fukushima, which is actually 250 km from the capital.