Radiation fallout reaches the US
Radioactive fallout from Japan's crippled nuclear plant has reached the US, with experts saying there is a small chance it could soon reach western Europe.
Readings of the radiation in southern California are said to be far below levels which could pose a health hazard, however.
The evacuation of foreign nationals from the disaster-hit country gathered pace yesterday as the situation at the dangerously overheated nuclear facility continued to deteriorate.
The emergency was sparked by last Friday's 9.0-magnitude earthquake and tsunami which has left more than 6,500 dead and over 10,300 missing.
A US diplomat with access to radiation tracking by the UN's Comprehensive Test Ban Treaty Organisation cited initial readings from a California-based measuring station.
These were "about a billion times beneath levels that would be health threatening,"he said.
The Nuclear Energy Agency said radiation from the plant was likely to reach everywhere in the northern hemisphere but in extremely small quantities.
Ted Lazo, who is responsible for radiation protection, said: "The quantities you will detect are very very small and certainly in the UK would pose absolutely no health risk whatsoever, but it will be detectable."
The Japanese authorities yesterday raised the rating of the crisis to a level five from a level four on a seven-point international scale for nuclear incidents.
This puts it on par with the 1979 Three Mile Island accident in Pennsylvania.
Meanwhile, the humanitarian crisis facing survivors of the tsunami continued to deteriorate, with freezing temperatures and food shortages putting lives in peril.
Increasing numbers of people are being forced to scavenge for food in the debris of their homes.
Dozens of elderly people have succumbed to hypothermia, with 287,000 households still without electricity, and rescuers are also struggling to get supplies of medicines to hospitals in the most isolated areas.
Survivors and rescue workers stood in the snow to observe a minute's silence at 2.46pm local time, exactly one week after the earthquake struck.
Yukio Edano, Japan's chief cabinet secretary, admitted there had been mistakes made in the response to the crisis.
"In hindsight, we could have moved a little quicker in assessing the situation and co-ordinating all that information and provided it faster," he said.
Workers at the plant continued using fire hoses to spray water into a pool containing spent fuel rods that boiled dry when the cooling system was knocked out by the tsunami.
The company which owns the plant said its electricity had been restored to some of the reactors yesterday, enabling it to restart the cooling system, after a temporary power line was put in.