Under pressure from international organizations, yesterday the Japanese government and the nuclear reactor operating company TEPCO admitted that one of the reactors at Fukushima underwent a meltdown. The fuel rods had become completely exposed to the air, then melted, and molten radioactive fuel fell to the base of the containment vessel, eating through the floor and causing an uncontrollable radiation leak that is still persisting. Radioactive water is still leaking into the ocean.
In the meantime seaweed harvested offshore has shown five times the allowable level of radiation for food products. And sewage in Tokyo is now radioactive, they suspect as a result of fallout in rain water. Both the seaweed and sewage showed high levels of cesium 137, which has half-life of 30 years.
It will be years before the leaking radiation is controlled. Contaminated water is also leaking into the water table from the reactors causing radiation in drinking water.
The explosion that occurred as a result of the meltdown did release large amounts of radiation into the atmosphere, which was detected in North America in water, milk, and the air. The Japanese company TEPCO at the time called this a hydrogen gas explosion, but it is now recognized as a nuclear meltdown similar to the accident at Chernobyl. The Japanese company and government have been continuously criticized for downplaying the serious nature of the disaster and taking inadequate measures to protect citizens from radiation dangers.