Concerns about food safety have spread to Tokyo, and prompted U.S. officials to halt the import of certain foods from Japan, as rising black smoke at the country's crippled nuclear plant spurred the overnight evacuation of workers.
Officials from the Tokyo Water Bureau said Wednesday that the level of radiation detected in the city's tap water had risen to more than twice the recommended level for infants.
Tests at a downtown Tokyo treatment plant that filters much of the city's tap water showed elevated levels of iodine-131 at a concentration of 210 becquerels per litre.
Because babies are more susceptible to developing thyroid cancer as a result of exposure to radioactive iodine, parents in the Tokyo area are being advised to limit how much tap water they give their infant children.
But, even though the level is more than twice the 100 becquerels per litre experts say is safe for infants to consume, older children and adults are being told they have no reason to fear water from their taps
"Even if you drink this water for one year, it will not affect people's health," Japan's Chief Cabinet Secretary Yukio Edano told reporters.
The recommended limit for adult consumption is 300 becquerels per litre.
For the 39 million people who call the greater Tokyo area home, the concerns over water contamination come amid growing warnings about radiation levels in food.
Increased radiation has been detected in raw milk and vegetables grown near the Fukushima Dai-ichi power plant crippled since the twin natural disasters struck off Japan's northeastern coast on March 11.
Governors of four prefectures -- Fukushima, Ibaraki, Tochigi and Gunma -- have been told to halt shipments of a range of fresh produce including caluiflower, cabbage, spinach, and broccoli. The governors of another 6 nearby prefectures -- Miyagi, Yamagata, Niigata, Nagano, Saitama and Chiba -- have been told to step up radiation monitoring of farm products there.
A growing list of countries including China, Malaysia, South Korea and Taiwan have begun monitoring radiation levels of food imported from Japan.
But the United States is the first to block imports of certain products from the radiation-affected part of northeastern Japan altogether.
Announcing the escalation from its previous commitment to monitor imports, the U.S. Food and Drug Administration said it will now halt dairy products and produce from the region at entry. Other foods, including seafood, will continue to be sold after they are screened for radiation.
The governments of South Korea and Hong Kong are now reportedly considering similar bans.
Radiation reaches Europe
Authorities said trace amounts of radiation have reached Iceland, and are expected to reach France and elsewhere in Europe, but stressed it does not pose a health risk.
A plume carrying radioactive iodine was detected in Iceland, according to the country's Radiation Safety Authority.
But it was "less than a millionth" of what was found in Europe following the 1986 Chernobyl disaster.
"We thus conclude that there is no reason to worry about radioactivity levels in Iceland, nor anywhere in Europe, resulting from the nuclear accident in Japan," Sigurdur Emil Palsson, head of emergency preparedness, told The Associated Press.
Costliest Crisis
At the tsunami-stricken plant in Fukushima, meanwhile, setbacks continue to plague efforts to contain leaking radioactive steam.
The plant's operator had managed to restore power to all six of the damaged facility's reactor units late Tuesday, sparking hopes its crucial cooling systems could be brought back online quickly.
But progress is intermittent as workers struggle amidst intermittent spikes in radiation, elevated pressure in the reactors, overheated storage pools and now, the heightened risk of touching off electrical fires.
In the latest incident, workers were evacuated Wednesday when black smoke began billowing from the Unit 3. Officials said there was no corresponding hike in radiation, but advised people living in the exclusion zone -- and beyond -- to limit their exposure to the outdoors anyway.
"We don't know the reason" for the smoke, Hidehiko Nishiyama of the Nuclear Safety Agency said.
A spokesperson for Japan's nuclear safety agency later said the workers would not be allowed to return overnight, as the smoke was too hard to detect in the darkness.
While confusion grips the struggle to contain the nuclear crisis, the Japanese government is getting a clearer idea of the type and scale of relief and rebuilding efforts in the other stricken areas.
The director of macroeconomic analysis at Japan's Cabinet Office told reporters on Wednesday that the crisis could wind up as the costliest natural disaster in history.
"The impact from the planned power outages is likely to be significant," Fumihira Nishizaki said as officials estimated the damage to roads, homes, factories and other infrastructure in the country's northeast could total more than US$310 billion, officials said.
The death toll from the earthquake and tsunami now exceeds 9,400, with another 15,600 still missing. Estimates peg the number of homeless at more than 350,000.
With files from The Associated Press
