Some parents are worried about the radiation their children might receive from the new full-body scanners at airports, but they might be better off zeroing in on a more systemic threat — radiation scans conducted for medical reasons. A new study published online Monday in the Archives of Pediatrics and Adolescent Medicine concludes that the average child will have absorbed radiation from more than seven scans by age 18, potentially raising his long-term risk of cancer.
Most of the scans rely on X-rays, but 3% of children got at least two CT scans, which deliver more radiation than X-rays. In general, a chest CT scan packs 100 times the radiation punch of a chest X-ray.
The researchers looked at the number and kind of radiation-based imaging procedures that were administered to 355,000 children covered by insurer UnitedHealth Group between 2005 and 2007. (More on Time.com: Do TSA Pat-Downs Work? Even Kids Know How to Blow Up a Plane)
More than 150,000 children — 42% — had nearly 437,000 scans. Children older than 10 were most likely to have had scans, though babies under 2 had them frequently too.
X-rays were most commonly ordered, but CT scans accounted for 12% of cases. Nearly 8% of kids got at least 1 CT scan; 3.5% received 2 or more. Most of the CT scans focused on the head, which is understandable considering they’re an important diagnostic tool when it comes to falls or sports-related accidents. Kids seem prone to both.
The study urged doctors to “optimize and ensure appropriate use” of radiation technology. But that’s challenging because the scans may be ordered by various physicians, none of whom may know that a particular patient has had previous scans. (More on Time.com: Do Dental Scans Put Your Child at Risk of Cancer?)
“While I can’t say any given procedure was appropriate or inappropriate, I think as a whole we have to make sure when these studies are being used, they are used only when they are absolutely necessary,” Adam Dorfman, the lead author and a pediatric cardiologist at the University of Michigan, told Reuters.
Once, when I brought my son to the pediatrician for a persistent cough, he relied on old-fashioned technology — the trusty stethoscope — to listen to his lungs. He said he didn’t hear anything alarming but couldn’t know for sure without an X-ray. He left the decision up to me, and I decided — with his blessing — to wait it out. (More on Time.com: Radiation May Be a Greater Cancer Risk for Adults Than Doctors Thought)
This same doctor confirmed my choice to forgo a head CT scan for my child when he was a baby. A well-respected craniofacial specialist had ordered the scan for my son when he was 6 months old to rule out a condition in which his skull bones were fused together. I thought — or desperately hoped — this wasn’t the case. When I asked my pediatrician for advice, he said it wasn’t irresponsible to skip the scan and rely on patience and time for a diagnosis. What I learned from these two situations is that it’s okay to trust your parental instints, and, perhaps more importantly, it’s okay to say “no thanks” to a doctor after doing due diligence. After all, it’s your body — or in this case, your child’s.