(Earth Focus: Episode 32) This original Earth Focus investigative report, looks at the untold stories behind three of the world's largest nuclear disasters: Three Mile Island, Chernobyl, and Fukushima.

According to government and industry officials, no one died as a result of Three Mile Island and only low doses of radiation -- equivalent to a single chest XRay were released. But many local residents disagree and cite medical evidence that radiation released from the Three Mile Island reactor was severe enough to cause disease and death. It's been 30 years but the controversy continues.

Chernobyl was the worse nuclear disaster in history. A new book, Chernobyl: Consequences of a Catastrophe says that almost a million people died as a result of the nuclear accident -- not 4,000 as The World Health Organization and the International Atomic Energy Agency claim. A screw up or a coverup? Earth Focus looks at evidence that links radioactive exposure to diminished intelligence, premature aging and a variety of other health conditions.

Given the severity of the accident in Fukushima and the inability of the government to provide action to safeguard large portions of its population, the Japanese government moved the goal posts on what is considered safe radiation exposure for children and nuclear workers. Japanese organized crime, the Yakuza, is now becoming actively involved in the cleanup of radioactive waste.

Read a supplemental blog with updates on these issues.

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