A new peer-reviewed scientific study says the backscatter full-body imaging X-ray machines being used by the federal Transportation Security Administration could be fooled by terrorists who simply would mold explosives to conform to their bodies.
WND obtained an advance copy of the report, titled "An evaluation of airport X-ray backscatter units based on image characteristics," in which University of California scientists Leon Kaufman and Joseph Carlson demonstrated that packages of explosives contoured to the body or worn along the sides likely would not be detected by TSA X-ray units built to "see" hard edges and anatomical features, and used primarily to image the front and back of the body.
The article comes from Dr. David Brenner of Columbia's Center for Radiological Research, whose research includes estimating the risks of low dose X-ray exposures.
WND previously reported that Brennan has cautioned that it is "quite likely" that radiation from screening machines being installed nationwide by the TSA to use on airline passengers will cause cancer, especially among high-risk groups that include frequent fliers and children.
Join tens of thousands of Americans in a petition demanding action against the intrusive airport screening procedures implemented by Janet Napolitano and send a letter to Congress, President Obama and others telling them exactly what you think about the issue.
The issue has erupted into headlines and protests during this month as the agency rolled out new requirements that demand passengers go through a scanning process through which essentially nude images are produced for TSA agents to screen, or submit to a hands-on full-body pat-down that includes agents touching private areas of the passengers' bodies.
Lawsuits already have been filed over the apparent violations of the 4th Amendment to the U.S. Constitution, and various organizations are encouraging passengers simply to quit flying.
In sharing with WND a pre-publication copy of the Kaufman-Carlson paper, Brenner stressed once again that the TSA is depending upon government-sponsored research and manufacturers' specifications to deny or minimize risk, instead of independent scientific research published in peer reviewed journals.
The TSA declined to respond to a WND request for comment on the contents of the study.
"Even if the [X-ray] exposure were to be increased significantly, normal anatomy would make a dangerous amount of plastic explosive with tapered edges difficult if not possible to detect," Kaufman and Carlson wrote.
A further disadvantage is that the X-ray backscatter units are not effective at detecting explosive packages that are contoured to supplement the natural features of the body, even when the explosive packages are concealed on the front or the back of a person.
"It is very likely that a large (15-20 centimeter in diameter), irregularly-shaped, centimeter-thick pancake with beveled edges, taped to the abdomen, would be invisible to this technology, ironically, because of its large volume, since it is easily confused with normal activity," they noted. "Thus, a third of a kilo of PETN [explosives], easily picked up in a competent pat down, would be missed by backscatter 'high technology.'"
The authors used the X-ray backscatter technology to demonstrate how 40 grams of PETN, "a purportedly dangerous amount," could be made to fit into a 1.25 mm-thick pancake to be "virtually invisible" to the x-ray technology currently being used by the TSA.
By comparison, the "shoe bomber" was carrying 40 grams of PETN, and the "Christmas bomber" was carrying 80 grams of PETN, both amounts considered sufficient to blow a hole in an aircraft’s skin.
Studies conducted by Kaufman and Carlson have demonstrated how human subjects carrying as much as 320 grams of PETN plastic explosive could design packages to wear on their bodies that would be undetectable to the X-ray backscatter machines currently being used by TSA, "depending upon the geometry [of the hidden packages] and the detector efficiency in the backscatter unit."
To illustrate the point, Kaufman and Carlson demonstrated how a terrorist could tape to his abdomen a tapered pancake-shaped package, 20 centimeters in diameter and one centimeter thick at the center, filled with 320 grams of PETN plastic explosive and that the X-ray backscatter full-body scanning units being used by TSA could confuse it with normal anatomy.
They further demonstrated that a pancake-designed package 1.25 millimeters thick at the center, containing 40 grams of PETN, would be invisible to the TSA X-ray machines if taped to a terrorist's side at or just above the waist.
Regarding the potential to conceal explosives and weapons along the sides of the body, Kaufman and Carlson concluded: "It is also easy to see that an object such as a wire or a box-cutter blade, taped to the side of the body, or even a small gun in the same location, will be invisible."
Kaufman and Carlson's article was accepted on Nov. 9, 2010, for publication by Springer Science and Business Media.
A screen capture of the article’s abstract is shown below:
John Whitehead of the Rutherford Institute, who sued the government over the issue, told WND the procedures were instituted through the work of President Obama.
"Legislation has been proposed to mandate full-body scanners and make them the primary screening method in all U.S. airports by 2013, but Congress has yet to act on it," Whitehead said in a commentary.
"So we can thank President Obama for this frontal assault on our Fourth Amendment rights. Mind you, this is the same man who insisted that 'we will not succumb to a siege mentality that sacrifices the open society and liberties and values that we cherish as Americans,'" Whitehead said.
There seems to be considerable doubt about the constitutionality of the searches, too. Even Mo McGowan, a former director of TSA security operations, was uncertain.
"We're not dictating these events that are occurring. Events are happening across the world … driving us as a society to have to go to these measures," he said.
"I mean, nobody likes having their 4th Amendment violated going through a security line," he said. "But the truth of the matter is we're going to have to do it."
The procedures have been the focus of warnings even by the networks, who noted in their reports that even government officials admit such scanners would not have stopped the so-called "Christmas Day" bomber: