Radon coming from these materials exposes the entire population. There are radioactive elements in our food and water, and in the radioactive aerosols and gases in the air we breathe. Our bodies contained naturally occurring radioactive elements when we were born. Everyone reeives varying amounts of natural radiation, depending on the amount of naturally occurring radioactive elements in the soil and the elevation above sea level and other factors. Radiation can destroy cancerous cells in a tumor, sterilize medical products and foods, track medicine thoughout the body, date archaelogical and geological events, and turn water into steam for electricity.
Radioactive sensors are in smoke detectors, and uranium puts the gleam in dentures.
More than one million people in the United States safely work in occupations involving radaition, involving naval and civilian nuclear reactor engineering, health physics, radiochemistry, radiology, nuclear medical technology, and x-ray technology. Although they normally accumulate an average of about 100 millirems of radiation per year, guidelines developed by the U.S. Environmental Protection Agency allow workers in these occuptation to accumulate up to 5,000 mrem annually, in addition to their natural background exposures. For the general public, EPA guidlines set the acceptable limit of additional exposure from manmade sources at 100 mrem over background. The following statistics and comparisons help clarify the actual exposure to radiation that we may experience in our daily routines. Because we cannot see or feel radiation, people tend to magnify the perception of its risk.