TOKYO — A spike in radiation levels in Tokyo tap water spurred new fears about food safety Wednesday as rising black smoke forced another evacuation of workers trying to stabilize Japan's radiation-leaking nuclear plant.
Radiation has seeped into vegetables, raw milk, the water supply and seawater since a magnitude-9 quake and killer tsunami crippled the Fukushima Dai-ichi power plant nearly two weeks ago. Broccoli was added to a list of tainted vegetables Wednesday, and U.S. officials announced a block on Japanese dairy and other produce from the region.
The crisis is emerging as the world's most expensive natural disaster on record, likely to cost up to $309 billion, according to a government estimate Wednesday. The death toll continued to creep up, with more than 9,400 bodies counted and more than 14,700 people listed as missing.
Concerns about food safety spread Wednesday to Tokyo after officials said tap water showed elevated levels: 210 becquerels per liter of iodine-131 — more than twice the recommended limit of 100 becquerels per liter for infants.
"It is really scary. It is like a vicious negative spiral from the nuclear disaster," said Etsuko Nomura, a mother of two young children ages 2 and 5. "We have contaminated milk and vegetables, and now tap water in Tokyo, and I'm wondering what's next."
Infants are particularly vulnerable to radioactive iodine, which can cause thyroid cancer, experts say. The limits refer to sustained consumption rates, and officials urged calm, saying parents should stop giving the tap water to babies, but that it was no worry if the infants already had consumed small amounts.
They said the levels posed no immediate health risk for children or adults.
"Even if you drink this water for one year, it will not affect people's health," Chief Cabinet Secretary Yukio Edano said.
Tokyo residents shouldn't worry, Dr. Lim Sang-moo, director of nuclear medicine at the Korea Cancer Center Hospital, said in Seoul.
Parents might want to be more cautious if they have a choice about what water to drink — "nobody wants to drink radioactive water," he said. But "it's not a medical problem but a psychosocial problem: The stress that people get from the radioactivity is more dangerous than the radioactivity itself."
Experts also say iodine-131 dissipates quickly in the air, with half of it disappearing every eight days.
The unsettling new development affecting Japan's largest city, home to some 13 million in the city center and 39 million residents in the greater Tokyo area, came as nuclear officials struggled to stabilize the hobbled reactor 140 miles (220 kilometers) to the north.
The quake and tsunami that struck off the east coast March 11 knocked out the plant's crucial cooling systems.
Explosions and fires have erupted in four of the plant's six reactors, leaking radioactive steam into the air. Progress in cooling down the overheated facility has been intermittent, disrupted by rises in radiation, elevated pressure in reactors and overheated storage pools.
The plant operator had restored circuitry to bring power to all six units and turned on lights at Unit 3 late Tuesday for the first time since the disaster — a significant step toward restarting the cooling system.
It had hoped to restore power to cooling pumps at the unit within days, but experts warned the work included the risk of sparking fires as electricity is restored through equipment potentially damaged in the tsunami.
In a new setback, black smoke billowed from Unit 3, prompting another evacuation of workers from the plant Wednesday afternoon, Tokyo Electric Power Co. officials said, but they said there had been no corresponding spike in radiation at the plant.
"We don't know the reason" for the smoke, Hidehiko Nishiyama of the Nuclear Safety Agency said.
As a precaution, officials have evacuated a 12-mile (20-kilometer) radius around the plant and advised those up to 19 miles (30 kilometers) away to stay indoors to minimize exposure.
And for the first time, Edano suggested that those downwind of the plant, even those just outside the zone, should stay indoors with the windows shut tight.
Survivors, meanwhile, buried the tsunami dead in makeshift coffins, resorting to wrapping some bodies in blue tarps.
In Higashimatsushima, about 200 miles (320 kilometers) northeast of Tokyo, soldiers lowered bare plywood coffins into the ground, saluting each casket, as families watched from a distance. Two young girls wept inconsolably, their father hugging them tight.
"I hope their spirits will rest in peace here at this temporary place," said Katsuko Oguni, 42, a relative of the dead.
Hundreds of thousands remained homeless, squeezed into temporary shelters without heat, warm food or medicine and no idea what to call home after the colossal wave swallowed up cities along the coast.
Tomoko Hosaka in Tokyo, Tim Sullivan in Higashimatsushima, Mary Clare Jalonick in Washington and Foster Klug in Seoul, South Korea, contributed to this report.