How much nuclear radiation exposure will cause sickness? What amount will cause death? Will dangerous levels of radiation reach other countries, such as the United States? The primary cause of fear and panic in Japan, which extended to a 16% decline in Japan's Nikkei Stock Average this week, is not the danger of nuclear radiation exposure: The fear and panic is a result of the unknown.
For some perspective, consider some points made on the ABC News report, Radiation Reality Check:
- Radiation is all around us and even inside us at all times; it is a part of nature. Such common items as the potassium in bananas are radioactive.
- The average human being is exposed to 3.5 millisieverts of radiation annually. This amount of exposure is equivelent to 67 chest X-rays.
- A person would need to be exposed to roughly 1,000 millisieverts of radiation to cause sickness. A fatal dose is in the range of 5,000 millisieverts.
- At the scene of the fire at the nuclear power plant in Japan, the radiation level is approximately 400 millisieverts. At this level, a person would have to sit there for 2.5 hours to get sick.
Although there is no present danger of serious illness or death from radiation exposure, the Japanese people certainly are justified in their concern over the potential of a worst-case, Chernobyl-size event. But should Americans be buying iodide pills, geiger counters and emergency kits online? Should world financial markets decline in response to an unlikely yet terrifying possibility?
"Courage is knowing what not to fear." ~ Plato
People do not fear risk; they fear imagined consequences. The risk of being struck by lightening is extremely low but we imagine the horrific consequence and run for shelter in fear at the sound of thunder. Making matters worse, this misguided fear often distracts us from other perils that are real and present. For example, death by drowning in a rip current occurs more often than shark bites, which rarely result in death. The former is overlooked because the latter is more vivid and horrifying; thus the ocean swimmer's risk is increased because of fearing the wrong thing.
The human imagination is powerful; it influences thought and emotion, which directly affect our actions. But if a room is dark, must there be a monster inside? What opportunities might you miss because of fear that provokes an image that may or may not be real?
As Franklin D Roosevelt once said, "All we have to fear is fear itself." With regard to large numbers of people, do not fear what the herd fears, fear being trampled by the herd. If you hear someone yell, "Fire!", your best initial reaction is to sit still.