The level of public understanding of the environment is abysmal. Few can describe what it is, its component parts, its origins, or how to detect and analyze the components. Too few have felt the wonder of what lies in a handful of soil, a cup of water, or a bowl of food or a glass of milk. The fact that natural radioactivity is found in each of these is a revelation to most.
When performing environmental radioactive analyses of various samples of the components named above, natural radioactivity, often called background radiation, is common in all environmental samples.
For the analytical chemist this background is usually a nuisance. For the lay person it is truly an epiphany. A good understanding of this source of radioactivity is essential in understanding our environment.
This is the context within which radioactivity and its health effects should be discussed. Similarly, the world of nuclear medicine, radiation oncology, and radiology are also sources of badly needed context.
Natural radioactivity — http://www.physics.isu.edu/radinf/natural.htm — is everywhere around us in soil, water, air, and the food we eat. It has been there since the beginning of the Earth 5 billion years ago.
Remarkably, natural radioactivity was discovered by Antoine Henri Becquerel in 1896, 109 years ago. (Those concerned with the decline of education in the U.S., should ponder why that – 109 years after the discovery of natural radioactivity – the public is still so uninformed about it).
In the late 1800s, Lord Kelvin of England used Fourier