TOKYO | Japan’s government on Tuesday raised the crisis level of its damaged nuclear facility at Fukushima to 7, the highest level — placing the monthlong emergency on a par with the 1986 Chernobyl disaster in Ukraine, the world’s worst nuclear accident.
But the government tried to downplay the gravity of its announcement, saying that total radiation leakage at Fukushima has amounted to only 10 percent of Chernobyl levels and has decreased in recent days.
Speaking on Japanese TV on Tuesday night, Prime Minister Naoto Kan appealed for calm, saying Japan will get the Fukushima nuclear-power plant under control.
“Right now, the situation of the nuclear reactors at the Fukushima plant has been stabilizing, step by step. The amount of radiation leakage is on the decline,” he said. “But we are not at the stage yet where we can let our guards down.”
In raising the crisis level from 5 to 7, officials noted that radiation levels at Fukushima had spiked in the week after the March 11 earthquake and tsunami. Radiation has contaminated drinking water, milk, vegetables and seawater during attempts to contain the damage to the nuclear reactors.
Chief Cabinet Secretary Yukio Edano said the level-7 upgrade “reconfirms that this is an extremely major disaster.”
“We are very sorry to the public, people living near the nuclear complex and the international community for causing such a serious accident,” he said, noting that radiation has sickened only 21 workers, none seriously, and killed no one.
“The accident itself is really serious, but we have set our priority so as not to cause health damage,” Mr. Edano said.
The government’s announcement came two days after the ruling party, already suffering in popularity polls before the March 11 calamity, lost many seats in local elections Sunday.
Many who had voted the party into power in 2009 have complained that the government hasn’t been telling the whole truth about, or responding fast enough to, the post-tsunami nuclear crisis.
Meanwhile, Chinese Prime Minister Wen Jiabao phoned Mr. Kan on Tuesday and reportedly asked Japan to be careful about contaminating the Pacific Ocean, where many Chinese fishing trawlers operate.
Japan’s government has been conservative in interpreting data, and decided to upgrade to level 7 after compiling data and estimates over the past month.
“We have refrained from making announcements until we have reliable data,” said nuclear safety agency spokesman Hidehiko Nishiyama. “The announcement is being made now because it became possible to look at and check the accumulated data assessed in two different ways,” he said, referring to measurements from his agency and Japan’s Nuclear Security Council.
As stipulated by the International Atomic Energy Agency (IAEA), a level-7 crisis means that a major release of radiation has occurred, including leakage of particles from the reactor core, with widespread impact on the environment and human health.
In Chernobyl, in Ukraine, a reactor exploded April 26, 1986, spewing a cloud of radiation over much of the Northern Hemisphere. A zone about 19 miles around the plant was declared uninhabitable, although some plant workers still live there for short periods and a few hundred other people have returned despite government encouragement to stay away.
In 2005, the Chernobyl Forum - a group comprising the IAEA and several other U.N. groups - said fewer than 50 deaths could be confirmed as being connected to Chernobyl, according to the Associated Press. It also said the number of radiation-related deaths among the 600,000 people who helped deal with the aftermath of the accident would ultimately be around 4,000.
The U.N. health agency, however, has said about 9,300 people are likely to die of cancers caused by radiation. Some groups, including Greenpeace, have put the numbers 10 times higher.
This article is based in part on wire service reports.