Tokyo Governor Shintaro Ishihara has appealed to Tokyo's 13-million residents to remain calm after elevated levels of radioactive iodine were detected Wednesday in the city's water supply.
The appeal came as officials suspended work at the crippled Fukushima nuclear plant 250 kilometers north of the capital. Dark smoke began rising late in the afternoon from the plant's number 3 reactor, forcing officials to evacuate crews who are struggling to restore power to the plant's crucial cooling systems.
Officials said they have not yet determined the cause of the smoke, which had eased but not stopped by early evening. There was no reported spike in radiation levels.
In Tokyo, officials announced they have detected radioactive iodine at one of the city's main water treatment plants at levels that are within acceptable levels for adults but more than twice the acceptable level for infants. They urged parents not to use the water to mix formula for children under one year old.
The announcement prompted a rush to purchase bottled water across the city. Authorities appealed to residents not to horde bottled water, warning all available supplies are needed for hundreds of thousands of people left homeless by the March 11 earthquake and tsunami.
In a television appearance, Ishihara urged residents to stay calm and, in his words, “try to consume water wisely.”
Hours earlier, the government expanded restrictions on the sale of milk and leafy vegetables from areas around the damaged Fukushima nuclear plant, which has been leaking radiation into the environment since a massive earthquake and tsunami on March 11. The U.S. has also announced a ban on all imports of milk and milk products, fresh fruit and vegetables from four Japanese prefectures surrounding the nuclear plant.
Officials announced earlier in the day that electricity had been restored to the control room at Unit 3, considered the most dangerous of the six reactors because it is the only one that uses a mix of uranium and plutonium in its fuel rods. Workers are seeking to restore electricity to the water pumps that cool the fuel rods, preventing them from overheating and sending out more radiation.
Earlier Wednesday, power company officials said they were intensifying efforts to pump sea water into the damaged number 1 reactor after temperatures inside the core rose to about 400 degrees Celsius — well above the 300-degree temperature at which it is designed to operate. NHK Television said the temperature had come down to about 360 degrees by 11 a.m.
Further north, about 300,000 earthquake and tsunami survivors remain in poorly equipped shelters as authorities struggle to reach them with food and other provisions. National Police said Wednesday the overall toll from the disaster has risen to more than 9,400 confirmed dead and more than 14,700 missing.
Government officials said the total cost of the disaster could exceed $300 billion. The World Bank estimated the cost a day earlier at up to $235 billion.
Officials said the radiation levels in the Tokyo water were about double the safety standard for infants. The treatment plant in central Tokyo serves residents in central and western parts of one of the world's largest cities.
Chief cabinet secretary Yukio Edano told reporters earlier that people should avoid eating a wide range of leafy vegetables including cabbage, broccoli and cauliflower grown in areas around the nuclear plant.
He said the radiation levels on the vegetables are not sufficient to affect human health if eaten for a short period. He said the government is acting now because of the likelihood that contamination from the nuclear plant will continue “for some time.”
Early Wednesday, a 6.0 magnitude earthquake struck near the troubled nuclear power plant but there were no immediate reports of damage or injury.