May 1, 2011

1 min read

Google Logo Add Us On GoogleAdd SciAm

Exposed: Medical Imaging Delivers Big Doses of Radiation

By Mark Fischetti

Join Our Community of Science Lovers!

Americans are exposed to much more ionizing radiation (the potentially harmful type) than they were 30 years ago. Greater use of medical imaging such as CT scans accounts for almost all the increase. The tests can reveal serious health threats, of course, but they come with risks.

Radiation experts recommend that the public receive less than one millisievert a year beyond natural background radiation (3.1 mSv), not counting medical tests. As shown, common sources such as airport scanners fall far below that recommendation, suggesting that anxiety about certain technologies is unwarranted.

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Among medical tests, CT scans are the greatest concern. Studies indicate as many as one third are prescribed unnecessarily. The average exposure for one scan is 7.1 mSv, according to David Schauer, executive director of the National Council on Radiation Protection and Measurements. “There is growing consensus that CT manufacturers should reduce CT scans to less than 1 mSv,” he says, adding that at a February meeting, companies indicated new technology could make that possible.

 

Also, see this Web exclusive on how much radiation we get from common sources.

Mark Fischetti was a senior editor at Scientific American for nearly 20 years and covered sustainability issues, including climate, environment, energy, and more. He assigned and edited feature articles and news by journalists and scientists and also wrote in those formats. He was founding managing editor of two spin-off magazines: Scientific American Mind and Scientific American Earth 3.0. His 2001 article “Drowning New Orleans” predicted the widespread disaster that a storm like Hurricane Katrina would impose on the city. Fischetti has written as a freelancer for the New York Times, Sports Illustrated, Smithsonian and many other outlets. He co-authored the book Weaving the Web with Tim Berners-Lee, inventor of the World Wide Web, which tells the real story of how the Web was created. He also co-authored The New Killer Diseases with microbiologist Elinor Levy. Fischetti has a physics degree and has twice served as Attaway Fellow in Civic Culture at Centenary College of Louisiana, which awarded him an honorary doctorate. In 2021 he received the American Geophysical Union’s Robert C. Cowen Award for Sustained Achievement in Science Journalism. He has appeared on NBC’s Meet the Press, CNN, the History Channel, NPR News and many radio stations.

More by Mark Fischetti
Scientific American Magazine Vol 304 Issue 5This article was published with the title “Exposed: Medical Imaging Delivers Big Doses of Radiation” in Scientific American Magazine Vol. 304 No. 5 ()
doi:10.1038/scientificamerican052011-3YMD6j2WnZN2bFM28huLZn
View This Issue

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe