Workers loaded trucks with boxes of bottled water to distribute across the city today after residents cleared store shelves following warnings that Tokyo's tap water had elevated radiation coming from Japan's tsunami-damaged nuclear complex.
Anxiety over food and water supplies soared a day after city officials reported that radioactive iodine in the tap water was measured at levels considered unsafe for babies over the long term.
"The first thought was that I need to buy bottles of water. I also don't know whether I can let her take bath," real estate agent Reiko Matsumoto said of her daughter, Reina, age 5. "I am very worried."
Tokyo supermarket clerk Toru Kikutaka said water sold out almost immediately after the news broke yesterday, despite a limit of two, 2-litre bottles per customer. "I've never seen anything like this," he said, surveying the empty shelves.
The panic in Japan's largest city, home to around 13 million people, added to growing fears over the nation's food supply as nuclear workers at the Fukushima Dai-ichi plant 220 kilometres to the north struggled to regain control of the facility.
The nuclear power plant has been leaking radiation since the tsunami engulfed its cooling systems, leading to explosions and fires in four of its six reactors. After setbacks and worrying black smoke forced an evacuation, workers were back to work Thursday, said Hidehiko Nishiyama of the Nuclear and Industrial Safety Agency.
Government spokesman Yukio Edano sought to allay fears over the tap water readings.
"We ask people to respond calmly" to the water situation, he said at a briefing today. "The Tokyo metropolitan government is doing its best."
Households with infants will get three, half-litre bottles of water each - a total of 240,000 bottles - city officials said, begging Tokyo residents to buy only what they need for fear that hoarding could hurt the thousands of people without any water in areas devastated by the March 11 earthquake and tsunami.
Nearly two weeks after the magnitude-9 quake, some 660,000 household still do not have water in Japan's northeast, the government said Thursday. Electricity has not been restored to some 209,000 homes, Tohoku Electric Power Co. said.
The figures were a reminder of the grim humanitarian situation that hundreds of thousands continue to face in the wake of twin disasters that are proving to be the most costly natural disaster on record. Damages are estimated at up to $309 billion, the government said.
Hundreds of thousands remain homeless, squeezed into temporary shelters without heat, warm food or medicine and no idea what to call home after the colossal wave swallowed up communities along the coast and dozens of strong aftershocks continued to shake the nation.
Fears about food safety began to spread overseas as radiation seeped into raw milk, seawater and 11 kinds of vegetables, including broccoli, cauliflower and turnips, from areas around the plant.
The latest data showed sharp increases in radioactivity levels in a range of vegetables. In an area about 40 kilometres northwest of the nuclear plant, levels for one locally grown leafy green called kukitachina measured 82 times the government limit for radioactive cesium and 11 times the limit for iodine.
The U.S. and Australia said they were halting imports of Japanese dairy and produce from the region near the facility; Hong Kong said it would require that Japan perform safety checks on meat, eggs and seafood, and Canada said it would upgrade controls on imports of Japanese food products by requiring documents verifying their safety.
Concerns also spread to Europe. In Iceland, officials said they measured trace amounts of radioactive iodine in the air but assured residents it was "less than a millionth" of levels found in European countries in the wake of the 1986 Chernobyl disaster.
The overall situation at the Fukushima plant remains of serious concern, the International Atomic Energy Agency said. The deposition of radioactive iodine and cesium varies across 10 prefectures on a day to day basis but "the trend is generally upward," said Graham Andrew, senior adviser to IAEA chief Yukiya Amano.
Nuclear workers have struggled for days to stabilize and cool down the overheated plant. Edano said workers were laboring steadily and the situation was "not urgent."
"As of now, the important thing we have been working on is to prevent deterioration. We should not be too optimistic," he said. "We are moving cautiously."
Worrisome Unit 3 has finally stopped belching black smoke, a Tokyo Electric Power Co. spokesman said today, a day after a plume forced an evacuation of nuclear workers. However, white smoke was rising intermittently from two other units, spokesman Masateru Araki said.
Officials have evacuated residents within 20 kilometres of the plant and advised those up to 30 kilometres away to stay indoors to minimise exposure.
Radioactive iodine is short-lived, with a half-life of eight days - the length of time it takes for half of it to break down harmlessly. However, experts say infants are particularly vulnerable to radioactive iodine, which can cause thyroid cancer.
Tokyo tap water tested with 210 becquerels of iodine-131 per liter of water - more than twice the recommended limit of 100 becquerels per liter for infants. Another measurement taken later at a different site showed the level was 190 becquerels per liter. The recommended limit for adults is 300 becquerels.
Today, officials warned that tap water in Kawaguchi City in Saitama just north of Tokyo also showed high levels of radiation. Levels of radioactive iodine at a purification plant measured 210 becquerels, said Shogo Misawa, a Health Ministry official.
The limits refer to sustained consumption rates, and officials said parents should stop feeding tap water to babies but that it was no problem if the infants already had consumed small amounts.
The amounts are too low to pose any real risk, even to infants who are being fed water-based formula or to breast-fed infants whose mothers drink tap water, said Dr. Harold Swartz, a professor of radiology and medicine at Dartmouth Medical School in the U.S.
That was small consolation for Matsumoto, Reina's mother in Tokyo.
"I had had this premonition that such things could happen when this nuclear power plant accident broke out," she said. "And, I really don't know what I can do now. They had been saying we would be OK. But, now this is happening and I really don't know what we can do."
Associated Press writers Yuri Kageyama, Tomoko A. Hosaka, Jeff Donn, Kaori Hitomi and Jean Lee in Tokyo, Lindsey Tanner in Chicago and Veronika Oleksyn in Vienna contributed to this report.