Cancer risk from airport scanning for frequent flyers
25 March 2011
Experts are calling for a review of airport security screening with whole-body X-ray scanners, suggesting the radiation exposure is a public health issue.
Controversy in the US over backscatter scanners, which use ionising radiation to detect weapons, explosives and other prohibited items, comes as Australia moves to introduce whole-body screening in the second half of 2011.
(Ionising radiation can damage the DNA in cells, potentially increasing the risk the cells will become cancerous. Examples of ionising radiation include X-rays and cosmic rays.)
In the latest issue of the journal Radiology, a researcher in the field said while the radiation doses associated with backscatter scanners were safe for people travelling a few times each year, frequent flyers faced higher risk, and the long-term, public health consequences were concerning.
"Given the larger numbers of scans involved, potentially up to 1 billion each year in the United States, there is a substantial likelihood that, among the scanned population, there will be some cancers induced by the associated radiation exposure", he wrote.
Millimetre-wave scanning was feasible and practical for whole-body scans and the radiation was non-ionising, he said.
According to the Australian Radiation Protection and Nuclear Safety Agency, the amount of radiation received during a backscatter scan was 200 to 1000 times less than that received during a chest X-ray and comparable to 2 minutes of flight at cruising altitude.
"The radiation risk resulting from the use of backscatter scanners is very small, even for a child or a pregnant woman", the agency said.
Whole-body backscatter scanners have been standard at US airports since the 2009 'underwear bomber' incident.
The type of screening technology to be adopted by Australian airports will be decided by their respective governing corporations.
Last Reviewed: 25 March 2011
- 1. Brenner DJ. Are x-ray backscatter scanners safe for airport passenger screening? Radiology 2011; 259: 6-10. doi: 10.1148/radiol.11102347. http://radiology.rsna.org/content/259/1/6.extract (accessed Mar 2011).
2. Schauer DA. Does security screening with backscatter x-rays do more good than harm? Radiology 2011; 259: 12-6. doi: 10.1148/radiol.11102376. http://radiology.rsna.org/content/259/1/12.extract (accessed Mar 2011).
3. Australian Radiation Protection and Nuclear Safety Agency. Airport passenger screening technologies (updated 15 Dec 2010). http://www.arpansa.gov.au/RadiationProtection/Factsheets/is_AirportScreening.cfm (accessed Mar 2011).
