“From now on, we will continue to handle it in a state of maximum alert,” he said. Mr Kan’s comments came after the Tokyo Electric Power Company (Tepco), the operators of the Fukushima plant, confirmed that plutonium had been detected, for the first time, in two out of five soil samples. Tepco said the levels of plutonium were not harmful to human health, but experts said the discovery suggested the reactor’s containment mechanism had been breached.