Japan on Tuesday (April 12th) raised the severity level of the crisis at its crippled Fukushima Dai-ichi nuclear plant, ranking it on par with the 1986 Chernobyl disaster. In raising the rating from 5 to 7 -- the highest level on the international scale -- Japanese nuclear regulators cited cumulative radiation leaks contaminating the air, tap water, vegetables and seawater. Other factors include damage to the plant's buildings and accumulated radiation levels for its workers. At the same time, Japanese officials have played down any health effects, saying the leaks amount to only a tenth of the radiation released during the Chernobyl disaster. However, they also acknowledge it could eventually exceed Chernobyl's emissions if the crisis continues.