The full body imaging scanners now in use at many airports around the country have generated a lot of controversy. The U.S. Government Accountability Office said the TSA was deploying the machines without fully testing them, concerns were raised about privacy, and others have questioned the adverse health effect of some of the machines, which function as low-level X-Ray machines. Now ProPublica, the "independent, non-profit newsroom that produces investigative journalism in the public interest," has just published a scathing report accusing the TSA of "marching millions of airline passengers through the scanners, parting ways with European countries that concluded radiation from routine airport use poses a health risk."

What follows is an excerpt of ProPublica's longer article, by reporter Michael Grabell. He finds that a 1998 safety panel was reassured X-ray body scanners wouldn't see widespread use. Now research suggests that "anywhere from six to 100 U.S. airline passengers each year could get cancer from the machines." But considering all the millions of people who fly every year, is that such a high price to pay for first-rate security theater? Here's the story, which was produced in conjunction with PBS NewsHour:

In 1998, a panel of experts evaluated a new device that beamed X-rays at people to detect weapons and contraband hidden underneath their clothing. The experts, convened by the Food and Drug Administration, raised questions about the machine because it violated a longstanding principle in radiation safety — that humans shouldn’t be X-rayed unless there is a medical benefit.

One panelist said it was “a slippery slope.” The device was already deployed in prisons. What was next, panelists asked, airports? Today, the Transportation Security Administration has begun marching millions of airline passengers through the X-ray body scanners, parting ways with countries in Europe and elsewhere that have concluded that such widespread use poses an unacceptable health risk. The TSA is rolling out the X-ray scanners despite having a safer alternative, a scanner that uses a technology known as millimeter waves and that the agency says is just as effective.

The TSA has repeatedly defined the scanners as “safe,” glossing over the accepted scientific view that even low doses of ionizing radiation increase the risk of cancer. Research suggests that anywhere from six to 100 U.S. airline passengers a year could get cancer from the machines. “Even though it’s a very small risk, when you expose that number of people, there’s a potential for some of them to get cancer,” said Kathleen Kaufman, the former radiation management director in Los Angeles County and a member of the FDA panel.

Robin Kane, the TSA’s assistant administrator for security technology, said no one would get cancer from the scanners, because the radiation they emit is minute: “It’s a really, really small amount relative to the security benefit.” Terrorist attacks using explosives concealed on the body have convinced many radiation experts that scanners’ low radiation dose is justified.

Kane also said the TSA uses both the X-ray and millimeter-wave scanners because keeping “multiple technologies in play” would increase competition to build “the better mousetrap.”

As part of a ProPublica/PBS NewsHour investigation, reporters reviewed transcripts from the regulatory hearings, examined scientific studies, surveyed foreign countries’ security policies and read through hundreds of internal TSA emails. Most of the news coverage on body scanners has focused on privacy. While some stories have raised the specter of radiation, this is the first to trace the history of the scanners and document the gaps in regulation that allowed them to avoid rigorous safety evaluation. While the full story can be found here, the main findings are:

  • Even though airport X-ray scanners, known as backscatters, deliberately expose humans to radiation, they are not medical devices so are subject to fewer regulations than X-ray machines used in doctors’ offices. The body scanner is classified as an electronic product; as a result, the FDA did not have to approve the device before it was sold.
  • The 1998 advisory panel recommended that the FDA establish mandatory government safety regulations for the X-ray body scanners. Instead, the agency opted for a voluntary standard set by a trade group largely comprising manufacturers and government agencies that wanted to use the machine. FDA officials said the decision was made because of congressional guidance to use industry standards wherever possible and because of a lack of resources.
  • The government used to have 500 people examining the safety of electronic products emitting radiation. But with staff pulled away for other priorities, it now has about 20. There is a regulation for X-rays scanning baggage — but none for X-rays scanning people at airports.
  • Even after 9/11, X-raying a person for anything other than a medical exam remains taboo in most of the industrialized world. In July, the European Parliament passed a resolution that security “scanners using ionizing radiation should be prohibited.” Although the United Kingdom uses the X-ray scanner for “secondary screening,” such as when a passenger sets off the metal detector, almost all developed countries have decided to forgo body scanners or use only the millimeter-wave machines.
  • The TSA says the scanners are safe for all fliers, including pregnant women. But a report by France’s radiation safety agency specifically warned against scanning pregnant women. In addition, the Federal Aviation Administration has advised pregnant pilots and flight attendants that the machine, coupled with their time in the air, could put them over their occupational limit for radiation exposure and that they might want to adjust their work schedules accordingly. No similar warning has been issued for pregnant frequent fliers.
  • The X-ray scanner’s manufacturer, Rapiscan Systems, increased its lobbying expenditures from less than $130,000 in 2006 to nearly $420,000 in 2008. It hired former legislative aides of key lawmakers, opened and expanded plants in their districts and started a political action committee that contributed heavily to their campaigns. In 2009, Rapiscan won a $173 million multiyear contract for the backscatters. Rapiscan Executive Vice President Peter Kant said the company needed to increase its lobbying to counter “misinformation” about the scanner. The lawmakers either declined to comment or said the lobbying, contributions and local connections had nothing to do with the TSA’s decision to purchase Rapiscan machines. The TSA said the contract was bid competitively.

About 250 X-ray scanners are currently in U.S. airports, along with 264 body scanners that use millimeter waves. In Rapiscan’s Secure 1000 scanner, a passenger stands between two large blue boxes and is scanned with a pencil X-ray beam that rapidly moves across and up and down the body. The machine uses an extremely low level of ionizing radiation, a form of energy that has been shown to strip electrons from atoms and damage DNA, potentially leading to cancer.

In the other machine, a ProVision made by L-3 Communications, a passenger enters a chamber that looks like a round phone booth and is scanned with millimeter waves, a form of low-energy radio waves, which have not been shown to strip electrons from atoms or cause cancer.

Humans are constantly exposed to ionizing radiation from many sources. As a result, the risk from any single radiation source is often small. The dose from the X-ray body scanner is roughly one-thousandth of a chest X-ray.
It’s mainly cumulative exposure that can lead to cancer. The authoritative report on the issue by the National Academy of Sciences concluded there was “no compelling evidence” that any level of radiation has zero risk of cancer.

Determined to fill a critical hole in its ability to detect explosives, the TSA plans to have body scanners operating at nearly every security lane in America by 2014. Officers will direct every passenger, including children, to go through either a metal detector or a body scanner, and the passenger’s only alternative will be to request a physical pat-down.

By Michael Grabell, ProPublica (here's the longer article); Miles O’Brien and Kate Tobin of PBS NewsHour contributed to this report.