GENEVA -- Infants exposed to radiation near Tokyo Electric Power Co.'s damaged nuclear power plant have a higher risk of developing cancer, though the threat outside the immediate area is low, the World Health Organization said Thursday in the first global assessment of risks from the 2011 disaster.
Girls in the most-affected area of Japan's northeastern Fukushima prefecture have as much as a 70 percent greater probability of thyroid cancer in their lifetimes, while boys' risk of leukemia is as much as 7 percent higher, the United Nations health agency said in a report.
TEPCO's Fukushima Dai-ichi plant was hit by a magnitude 9 earthquake and a huge tsunami on March 11, 2011, that forced about 160,000 people to evacuate. The disaster also left about 51 square miles as a no-go zone, some of it uninhabitable for decades. Doses of radiation were too low to affect fetal development or cause birth defects, and there's no increased health risk outside the prefecture, according to the WHO report.
"Outside the geographical areas most-affected by radiation, even in locations within Fukushima prefecture, the predicted risks remain low, and no observable increases in cancer above natural variation in baseline rates are anticipated," the Geneva-based WHO said in the 165-page report.
Meanwhile, Prime Minister Shinzo Abe, moving to ensure a stable energy supply despite public safety concerns after the Fukushima disaster, said Thursday that Japan will begin restarting its idled nuclear plants once new safety guidelines are in place later this year.
In a speech to Parliament, Mr. Abe pledged to restart nuclear plants that pass the tougher guidelines, expected to be adopted by a newly created independent watchdog agency, the Nuclear Regulation Authority, as early as July. But he did not specify when any of the reactors might resume operation.
News reports have suggested that it might take months, or even years, to make the expensive upgrades needed to meet the new safety standards.
All of Japan's 50 operable nuclear reactors were shut down after the triple meltdown at the Fukushima Dai-ichi plant, which spewed radiation across northern Japan after a huge earthquake and tsunami knocked out vital cooling systems. Two reactors were later restarted as an emergency measure to avert power shortages in the heavily populated region that includes the cities of Osaka and Kyoto.
Responding to public safety concerns, leaders from the previous Democratic Party government had vowed to slowly phase out nuclear power by the 2030s in favor of cleaner alternatives such as solar and wind power. But Mr. Abe, who took power after his Liberal Democratic Party won national elections in December, has vowed to shelve the planned phaseout, saying Japan needs stable and cheap electricity from nuclear power to compete economically.
Thursday's WHO findings confirm a preliminary report published in May that found people outside the most-affected area were exposed to relatively low doses of radiation. The continuing monitoring of children's health -- and of food and the environment -- remains important, the WHO said.
Japanese girls and women normally have a lifetime risk of 0.75 percent, and the additional risk for infant girls exposed to radiation in the most-affected area is 0.5 percent, the WHO said. The added risks in the second-most affected area are half those in the highest-dose location, the WHO said. More than twice as many thyroid cancers are diagnosed in women as in men, according to Cancer Research UK.
The U.N. agency said it deliberately used conservative assumptions that may have led it to overestimate the risks. "It's clear that more will be detected," Angelika Tritscher, acting director for WHO's food safety and zoonosis department, said Thursday at a Geneva briefing with reporters, referring to thyroid cancer. A zoonosis is an infectious disease transmitted between species.
The New York Times contributed.