If we must have body scanners, which don’t tell us about materials stored inside the body anyway, why not simply use the millimeter wave type, which don’t emit radiation? Well, explains the TSA, we wanted both types of technology, so there would be competition. And never mind the risks to those who fly.
For those who see these machines as essentially “security theater,” the notion of having between 6 and 100 extra American cancer cases per year is not going to sit very well. And it shouldn’t.
Michael Grabell’s report for ProPublica is extensive, so I’m excerpting enough for you to get a fraction of the historical background they lend to the piece, but I’d actually encourage you to read the entire thing, over at the ProPublica site. Also, later on this month they will be doing a television report in conjunction with the PBS NewsHour that focuses on these machines and the health risks that are associated with them.
One after another, 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.
“I think this is really a slippery slope,” said Jill Lipoti, who was the director of New Jersey’s radiation protection program. The device was already deployed in prisons; what was next, she and others asked — courthouses, schools, airports? “I am concerned … with expanding this type of product for the traveling public,” said another panelist, Stanley Savic, the vice president for safety at a large electronics company. “I think that would take this thing to an entirely different level of public health risk.”
The machine’s inventor, Steven W. Smith, assured the panelists that it was highly unlikely that the device would see widespread use in the near future. At the time, only 20 machines were in operation in the entire country.
“The places I think you are not going to see these in the next five years is lower-security facilities, particularly power plants, embassies, courthouses, airports and governments,” Smith said. “I would be extremely surprised in the next five to 10 years if the Secure 1000 is sold to any of these.”
Today, the United States 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 of even low-level radiation poses an unacceptable health risk. The government is rolling out the X-ray scanners despite having a safer alternative that the Transportation Security Administration says is also highly effective. . . .
Research suggests that anywhere from six to 100 U.S. airline passengers each year could get cancer from the machines. Still, the TSA has repeatedly defined the scanners as “safe,” glossing over the accepted scientific view that even low doses of ionizing radiation — the kind beamed directly at the body by the X-ray scanners — increase the risk of cancer. . . .
About 250 X-ray scanners are currently in U.S. airports, along with 264 body scanners that use a different technology, a form of low-energy radio waves known as millimeter waves.
Robin Kane, the TSA’s assistant administrator for security technology, said that no one would get cancer because the amount of radiation the X-ray scanners emit is minute. Having both technologies is important to create competition, he added.
“It’s a really, really small amount relative to the security benefit you’re going to get,” Kane said. “Keeping multiple technologies in play is very worthwhile for the U.S. in getting that cost-effective solution — and being able to increase the capabilities of technology because you keep everyone trying to get the better mousetrap.”
Determined to fill a critical hole in its ability to detect explosives, the TSA plans to have one or the other operating at nearly every security lane in America by 2014. The TSA has designated the scanners for “primary” screening: 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.
How did the United States swing from considering such X-rays taboo to deeming them safe enough to scan millions of people a year?
A new wave of terrorist attacks using explosives concealed on the body, coupled with the scanners’ low dose of radiation, certainly convinced many radiation experts that the risk was justified.
But other factors helped the machines gain acceptance.
Because of a regulatory Catch-22, the airport X-ray scanners have escaped the oversight required for X-ray machines used in doctors’ offices and hospitals. The reason is that the scanners do not have a medical purpose, so the FDA cannot subject them to the rigorous evaluation it applies to medical devices.
Still, the FDA has limited authority to oversee some non-medical products and can set mandatory safety regulations. But the agency let the scanners fall under voluntary standards set by a nonprofit group heavily influenced by industry.
As for the TSA, it skipped a public comment period required before deploying the scanners. Then, in defending them, it relied on a small body of unpublished research to insist the machines were safe, and ignored contrary opinions from U.S. and European authorities that recommended precautions, especially for pregnant women. Finally, the manufacturer, Rapiscan Systems, unleashed an intense and sophisticated lobbying campaign, ultimately winning large contracts.
Both the FDA and TSA say due diligence has been done to assure the scanners’ safety. Rapiscan says it won the contract because its technology is superior at detecting threats. While the TSA says X-ray and millimeter-wave scanners are both effective, Germany decided earlier this year not to roll out millimeter-wave machines after finding they produced too many false positives.
Most of the news coverage on body scanners has focused on privacy, because the machines can produce images showing breasts and buttocks. But the TSA has since installed software to make the images less graphic. While some accounts have raised the specter of radiation, this is the first report to trace the history of the scanners and document the gaps in regulation that allowed them to avoid rigorous safety evaluation.
Little research on cancer risk of body scanners
Humans are constantly exposed to ionizing radiation, a form of energy that has been shown to strip electrons from atoms, damage DNA and mutate genes, potentially leading to cancer. Most radiation comes from radon, a gas produced from naturally decaying elements in the ground. Another major source is cosmic radiation from outer space. Many common items, such as smoke detectors, contain tiny amounts of radioactive material, as do exit signs in schools and office buildings.
As a result, the cancer risk from any one source of radiation is often small. Outside of nuclear accidents, such as that at Japan’s Fukushima plant, and medical errors, the health risk comes from cumulative exposure.
In Rapiscan’s Secure 1000 scanner, which uses ionizing radiation, a passenger stands between two large blue boxes and is scanned with a pencil X-ray beam that rapidly moves left to right and up and down the body. In the other machine, ProVision, made by defense contractor 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.
Only a decade ago, many states prohibited X-raying a person for anything other than a medical exam. Even after 9/11, such non-medical X-raying 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” because of health risks. Although the United Kingdom uses the X-ray machine for limited purposes, such as when passengers trigger the metal detector, most developed countries have decided to forgo body scanners altogether or use only the millimeter-wave machines.
While the research on medical X-rays could fill many bookcases, the studies that have been done on the airport X-ray scanners, known as backscatters, fill a file no more than a few inches thick. None of the main studies cited by the TSA has been published in a peer-reviewed journal, the gold standard for scientific research.
Those tests show that the Secure 1000 delivers an extremely low dose of radiation, less than 10 microrems. The dose is roughly one-thousandth of a chest X-ray and equivalent to the cosmic radiation received in a few minutes of flying at typical cruising altitude. The TSA has used those measurements to say the machines are “safe.” . . .
Some scientists argue the danger is exaggerated. They claim low levels stimulate the repair mechanism in cells, meaning that a little radiation might actually be good for the body.
But in the authoritative report on low doses of ionizing radiation, published in 2006, the National Academy of Sciences reviewed the research and concluded that the preponderance of research supported the linear link. It found “no compelling evidence” that there is any level of radiation at which the risk of cancer is zero.
Radiation experts say the dose from the backscatter is negligible when compared to naturally occurring background radiation. Speaking to the 1998 FDA panel, Smith, the inventor, compared the increased risk to choosing to visit Denver instead of San Diego or the decision to wear a sweater versus a sport coat.
Using the linear model, even such trivial amounts increase the number of cancer cases. Rebecca Smith-Bindman, a radiologist at the University of California, San Francisco, estimated that the backscatters would lead to only six cancers over the course of a lifetime among the approximately 100 million people who fly every year. David Brenner, director of Columbia University’s Center for Radiological Research, reached a higher number — potentially 100 additional cancers every year.
“Why would we want to put ourselves in this uncertain situation where potentially we’re going to have some cancer cases?” Brenner asked. “It makes me think, really, why don’t we use millimeter waves when we don’t have so much uncertainty?”
But even without the machines, Smith-Bindman said, the same 100 million people would develop 40 million cancers over the course of their lifetimes. In this sea of cancer cases, it would be impossible to identify the patients whose cancer is linked to the backscatter machines.
How the scanners avoided strict oversight
Although they deliberately expose humans to radiation, the airport X-ray scanners are not medical devices, so they are not subject to the stringent regulations required for diagnostic X-ray machines.
If they were, the manufacturer would have to submit clinical data showing safety and effectiveness and be approved through a rigorous process by the FDA. If the machines contained radioactive material, they would have to report to the Nuclear Regulatory Commission.
But because it didn’t fit into either category, the Secure 1000 was classified as an electronic product. The FDA does not review or approve the safety of such products. However, manufacturers must provide a brief radiation safety report explaining the dose and notify the agency if any overexposure is discovered. According to the FDA, no such incidents have been reported.
Under its limited oversight of electronic products, the FDA could issue mandatory safety regulations. But it didn’t do so, a decision that flows from its history of supervising electronics.
Regulation of electronic products in the United States began after a series of scandals. From the 1930s to the 1950s, it was common for a child to go to a shoe store and stand underneath an X-ray machine known as a fluoroscope to check whether a shoe was the right fit. But after cases arose of a shoe model’s leg being amputated and store clerks developing dermatitis from putting their hands in the beam to adjust the shoe, the practice ended.
In 1967, General Electric recalled 90,000 color televisions that had been sold without the proper shielding, potentially exposing viewers to dangerous levels of radiation. The scandal prompted the creation of the federal Bureau of Radiological Health.
“That ultimately led to a lot more aggressive program,” said John Villforth, who was the director of the bureau. Over the next decade, the bureau created federal safety standards for televisions, medical X-rays, microwaves, tanning beds, even laser light shows.
But in 1982, the FDA merged the radiological health bureau into its medical-device unit.
“I was concerned that if they were to combine the two centers into one, it would probably mean the ending of the radiation program because the demands for medical-device regulation were becoming increasingly great,” said Villforth, who was put in charge of the new Center for Devices and Radiological Health. “As I sort of guessed, the radiation program took a big hit.”
The new unit became stretched for scarce resources as it tried to deal with everything from tongue depressors to industrial lasers. The government used to have 500 people examining the safety of electronic products emitting radiation. It now has about 20 people. In fact, the FDA has not set a mandatory safety standard for an electronic product since 1985.
As a result, there is an FDA safety regulation for X-rays scanning baggage — but none for X-rays scanning people at airports.
This is just amazing. I understand that cancer patients have been skeptical all along that these machines would affect their risk profiles (particularly skin-cancer patients, who avoid the sun as much as they can). But I hadn’t realized that the FDA had essentially bowed out of involving themselves—or that they were as understaffed as they appear to be right now.
I’ll tell you one thing: any Presidential candidate who promised to stand up to the TSA (and, to a lesser degree, the airlines) on behalf of the U.S. flying public would win in a landslide.