So that is the purring sound I heard:
"Study ties overuse of CT scans to cancer; Warns against needless tests" by Marilynn Marchione/Associated Press November 29, 2007
MILWAUKEE - Millions of Americans, especially children, are needlessly getting dangerous radiation from "super X-rays" that raise the risk of cancer and are increasingly used to diagnose medical problems, a new report warns.
Some specialists say curb these tests, particularly in children, who are more susceptible to radiation and more likely to develop cancer from it. The report was published in today's New England Journal of Medicine and paid for by federal grants.
The average American's total radiation exposure has nearly doubled since 1980, largely because of CT scans. Medical radiation now accounts for more than half of the population's total exposure; it used to be just one-sixth, and the top source was the normal background rate in the environment, from things like radon in soil and cosmic energy from the sun.
CT use continued to soar. About 62 million scans were done in the United States last year, up from 3 million in 1980. More than 4 million were in children. Ultrasound and MRI, or magnetic resonance imaging, scans often are safer options that do not expose people to radiation."
