Japan’s science ministry says 8 per cent of the country’s surface area has been contaminated by radiation from the crippled Fukushima nuclear plant.
It says more than 30,000 square kilometres of the country has been blanketed by radioactive caesium.
The ministry says most of the contamination was caused by four large plumes of radiation spewed out by the Fukushima nuclear plant in the first two weeks after meltdowns.
The government says some of the radioactive material fell with rain and snow, leaving the affected areas with accumulations of more than 10,000 becquerels of caesium per square metre.
Read More: Radiation covers 8pc of Japan