Published in the Hindu on November 28, 2011

The European Commission’s recent decision to ban the use of X-ray technology for full-body scanning at airports to avoid “jeopardising” the health and safety of passengers is a victory for millions of travellers. The legislation requires all the 27 member countries to follow “strict and mandatory safeguards” that comply with the “fundamental rights and protection of [passengers’] health.” This marks a sharp departure from the stand taken by the United States, which is planning to increase the number of such machines at airports. Though X-ray scanners expose passengers to only low levels of radiation, equivalent to that received in a few minutes of flying, any intentional use for purposes other than medical violates the basic tenets of radiation safety. That people are naturally exposed to ionising radiation every day is not an acceptable argument. Avoiding exposure, and reducing it where unavoidable, must be the cornerstone of radiation safety. Ionising radiation has a cumulative effect, and the risk of cancer exists even when the radiation dose is low — this was highlighted in a 2006 report of the National Academy of Sciences. The risk to an individual may be small. But the overall impact may not be so when the number of people exposed to radiation is large. The use of X-ray scanners becomes all the more questionable considering that millimetre-wave scanners — an equally efficient technology that uses radio waves — can be used for screening. Unlike X-rays, radio waves do not ionise the molecules of the body, and there is virtually no health risk. Nearly 250 millimetre-wave scanners are already in use in U.S. airports.

Security concerns seem to override health concerns in the U.S. Unlike radiation-emitting appliances in hospitals, X-ray scanners do not come under the preview of the Food and Drug Administration and are not subject to rigorous evaluations. The reason: they are not used for medical purposes. This raises serious concerns as regular and thorough monitoring of radiation dose by a competent authority is essential for all radiation emitting machines. Why the U.S. Transportation Security Administration is keen on equipping airports with more of these machines when a safer alternative is available remains a puzzle.