|original photograph by philip cosson showing the first comercial CT head scanner Image uploaded from the English Wikipedia. (Photo credit: Wikipedia)|
One of modern medicine's most valuable tools is the X-ray. But it comes with a dangerous price: ionizing radiation, a known carcinogen.
As recently as the early 1980s, X-rays accounted for just 11 percent of radiation exposure in Americans. Natural, background radiation accounted for most of the rest.
In the last 30 years, the use of X-rays and other radiation-producing diagnostic tests have skyrocketed. CT (computed tomography) scans, also called CAT scans, have gone from 3 million in the U.S. in 1980 to 70 million in 2006. A CT scan of the chest has the radiation dose of 100 routine chest X-rays.
A Columbia University study estimates that up to 2 percent of all cancers in the U.S. are caused by CT scans.