JAPAN HAS RAISED the severity level of the crisis at its crippled nuclear plant to rank it on par with the 1986 Chernobyl disaster, citing cumulative radiation leaks contaminating the air, tap water, vegetables and seawater.

Japanese nuclear regulators said the rating was being raised from 5 to 7 — the highest level on an international scale overseen by the International Atomic Energy Agency — after new assessments of radiation leaks from the Fukushima I plant since it was disabled by the March 11 tsunami.

The new ranking signifies a “major accident” with “wider consequences” than the previous level, including widespread health effects, according to the Vienna-based IAEA.

However, Japanese officials have played down any health effects of radioactive releases so far from the Fukushima plant. They said the leaks amount to only a tenth of the radiation emitted in the Chernobyl disaster, while acknowledging they eventually could exceed Chernobyl’s emissions if the crisis continues.

“This 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,” said government spokesman Yukio Edano.

But Edano told reporters that there was so far no “direct health damage” from the crisis. “The accident itself is really serious, but we have set our priority so as not to cause health damage.”

The revision came a day after the government added five communities to a list of places people should leave to avoid long-term radiation exposure. A 12-mile radius had already been cleared around the plant.

Officials from Japan’s Nuclear and Industrial Safety Agency said that the cumulative amount of radioactive particles released into the atmosphere since the incident had reached levels that apply to a Level 7 incident. Other factors included damage to the plant’s buildings and accumulated radiation levels for its workers.

“We have upgraded the severity level to 7 as the impact of radiation leaks has been widespread from the air, vegetables, tap water to the ocean,” NISA official Minoru Oogoda said.

The revision was based on cross-checking and assessments of data on leaks of radioactive iodine-131 and cesium-137, another spokesman said, adding:

We have refrained from making announcements until we have reliable data… the announcement is being made now because it became possible to look at and check the accumulated data assessed in two different ways.

The spokesman said that unlike in Chernobyl, there had been no explosions of reactor cores at the Fukushima I plant, although there were hydrogen explosions.

“In that sense, this situation is totally different from Chernobyl,” he said, further adding that the amount of radiation leaking from the plant was around 10 percent of that released in the Chernobyl accident.

A spokesman for plant operator TEPCO, however, said the company was still estimating the total amount of radioactive material that might be released by the accident.

AP