Andrew Karam, Popular Mechanics - A powerful earthquake caused a massive tsunami that crashed into Fukushima Daiichi Nuclear Power Plant and caused multiple nuclear reactor meltdowns.
The Japanese government recently compensated a worker who developed leukemia after receiving just under 20 mSv (about 2 rem) of radiation exposure from the accident. See article by Jerry Cuttler and James Welsh, the acute dose radiation exposure for predicting cancer is considered to be higher than 500 mSv. The 20 mSv dose that the Japanese government compensated a person for is far below the threshold considered to cause leukemia.
