George, I have googlled as you suggested and here is what I found:
QUOTE: " According to a 2012 Yomiuri Shimbun survey, 573 deaths have been certified as "disaster-related" by 13 municipalities affected by the Fukushima nuclear disaster. These municipalities are in the no-entry, emergency evacuation preparation or expanded evacuation zones around the crippled Fukushima nuclear plant. A disaster-related death certificate is issued when a death is not directly caused by a tragedy, but by "fatigue or the aggravation of a chronic disease due to the disaster"."
Other things I found containing the number 500 were:
QUOTE: " In April 2011, the United States Department of Energy published projections of the radiation risks over the next year for people living in the neighborhood of the plant. Potential exposure could exceed 20 mSv/year (2 rems/year) in some areas up to 50 kilometers from the plant. That is the level at which relocation would be considered in the USA, and it is a level that could cause roughly one extra cancer case in 500 young adults. Natural radiation levels are higher in some part of the world than the projected level mentioned above, and about 4 people out of 10 can be expected to develop cancer without exposure to radiation. Further, the radiation exposure resulting from the accident for most people living in Fukushima is so small compared to background radiation that it may be impossible to find statistically significant evidence of increases in cancer."
Lastly and significantly:
Quote: " A Japanese Research Company was assigned to find out the health effects and casualties caused by the disaster. They found that some deaths were early, during evacuation processes, while other deaths gradually happened after the disaster. The agency found out that the cause of these early deaths were due to the disruption of hospital operations, exacerbation of pre-existing health problems and the stress of dramatic changes in life. It is stated that the vast majority of people who died during their evacuation were elderly. 45 patients were reported dead after the evacuation of a hospital in Futaba due to lack of food, water and medical care as evacuation was delayed by three days. "
When you look closely, you inevitably find bias and hype behind the claims of anti-nuclear groups about the deaths and health effects of the Fukushima incident.