For anyone using their eyes, reading on this site, light is incredibly important!
Luminous (visible) light is part of a huge spectrum of radiation, which also includes marvelous microwaves, reliable radio-waves, useful ultraviolet, incandescent infra-red and finally, indispensable ionizing radiation. One interesting thing about ionizing radiation is that it gives an electrical charge to atoms in its path, including atoms in the human body.
All of us have been exposed to this naturally occurring ionizing radiation from the moment of conception… and will be for the rest of our lives. There is no known place where we can escape it! Interestingly, as a large portion of our natural radiation exposure is due to radioactive materials in the ground, and these isotopes are, of course, constantly decaying, the natural levels were a lot higher in the past.
One of our most common misconceptions, one generally accepted by scientists as well as laymen, is that ionizing radiation is inherently dangerous, no matter how little of it impacts and enters our bodies. This rather unique attitude to ionizing radiation means that it is generally more feared than almost anything else.
Let’s review how ionizing radiation relates to life. A very important question is: how is it possible that something so universally present can be hazardous, even at everyday levels? To explain this, we must consider how the natural environment in which we live came to be. Each one of us either follows the viewpoint of evolution or creation…
With respect to understanding this almost universally misunderstood radiation, either viewpoint leads to the same conclusion… let me explain:
The evolutionist talks about the gradual development of living organisms, within the natural environment surrounding them. The ‘little critters’ would adjust to the temperature, humidity, pressure, and of course radiation levels around them. Only those well-adjusted would thrive. Thus each critter is optimized for life within the natural levels around it.
The creationist talks about the provision of a world for the living organisms designated to live on it. The temperature, humidity, pressure, and of course radiation levels created would be suited to each ‘little critter’. Thus the natural levels around each critter are optimized for the critter living within it.
Just as people are exposed to visible light from the sun and stars, they are also bathed in this ionizing radiation. Soil, rock, water, meats, fruits and vegetables… even air has radioactive material in it. Radioactive material is also a natural part of the human body. Ionizing radiation is a part of the natural background for all living things, including humans. Large portions of the natural radiation we are exposed to are due to the decay of radioactive materials in the ground. Obviously, as these substances decay, they are continually reducing in quantity and the amount of radiation emitted is constantly (though very slowly!) reducing, too.
The amount of radiation that people receive daily from their surroundings and from the materials that make up their body is small compared to the amounts delivered to treat cancer. However, people in various parts of the world are exposed to wildly different amounts of radiation. Without going into the definition of the units used to measure this radiation, the annual values vary from 1 to 300, with the average being between 3 and 4.
Reassuringly, studies show that people residing in areas with the highest natural backgrounds of ionizing radiation are healthier and live longer than those who live in regions were the exposure is lower, (the concept behind this phenomenon is called hormesis - see the page on this site specific to this subject) demonstrating clearly that the increased radiation exposures we receive from nature by moving from one area to another are not dangerous.