Wednesday, December 30, 2009

Body scanner debate grows after attack

In the wake of an attempted terrorist attack on Christmas Day, there have been calls to increase the use of body scanners at airports. Umar Farouk Abdulmutallab had boarded a flight in Nigeria and flown to Amsterdam where he boarded Northwest Airlines Flight 253 en route to Detroit, Michigan. As the plane flew over the United States, Abdulmutallab attempted to explode a device sewn into his underpants, and that had remained undetected despite passing through security twice. 

President Obama has condemned the "systemic failure" of the 40 billion dollar US airport and airline security system that even allowed Umar Farouk Abdulmutallab on to a flight to Detroit on Christmas Day in the first place. Obama said last night that it was "totally unacceptable" that information on Abdulmutallab available to US intelligence had not been used to stop him flying. He said he had demanded answers as to what went wrong by tomorrow. Meanwhile officials have scrambled to plug gaps in the system.


Abdulmutallab's father, Alhaji Umaru Mutallab, a former First Bank PLC chairman, is reported to have become gravely concerned about their son. Mutallab had approached the US embassy in Abuja, reportedly in November, as well as Nigerian security officials, to voice concerns about his son. But questions are now being raised as to how the accused, who had a valid US travel visa, boarded a flight in Lagos to Amsterdam, despite being on a database listing individuals of concern to the authorities.

Anti-terrorist measures in Nigeria's airports are described as haphazard and there is corruption among police, customs and security officials. An unnamed Obama official quoted by the New York Times said, "The information was passed into the system but the expression of radical extremist views were very non-specific."

A US official told Reuters news agency the suspect's name was in a US database of suspected terrorists, but there had not been sufficient information to warrant putting him on the "no-fly" list. It is this fact that has particularly concerned President Obama. "When our Government has information on a known extremist and that information is not shared and acted on as it should have been, a systemic failure has occurred, and I consider that unacceptable," Obama said.

Security after 9/11

Aside a failure in passing on intelligence information there are concerns too that security screening at airports is not adequate enough. Airline passengers have seen increased security following several actual or attempted terrorist attacks in the last few years. Following 9/11 all sharp objects were banned from flights as the terrorists had apparently used box-cutters to aid their hijack. Passengers found themselves giving up many items previously seen as innocuous. Nail scissors and clippers, sewing and knitting needles and safety razers. Even metal cutlery provided for in-flight meals was replaced with plastic. 

After Richard Reid attempted to detonate explosives built into his shoes in December 2001 passenger found themselves having to remove their shoes for scrutiny as they passed though airport security. In addition lighters and matches were also banned as Reid had attempted to use a match to detonate his device. Authorities later found PETN with a triacetone triperoxide (TATP) detonator hidden in the lining of his shoes. Reid's attempt to use a lighter would have likely failed to trigger an explosion however. PETN is difficult to detonate. Dropping it or setting it on fire will typically not cause an explosion and an electrical charge is usually required. 

When the liquid bomb plot was uncovered in Britain in 2006 there was a major rethink and a swift reaction to airline security. Bombers had apparently planned to take liquid explosives on board aircraft hidden in drinks bottles. US authorities named two peroxides that could be used; acetone peroxide (TATP) and hexamethylene triperoxide diamine (HMTD). Both "are sensitive to heat, shock, and friction, can be initiated simply with fire or electrical charge, and can also be used to produce improvised detonators." According to The Guardian, police sources confirmed that the plot involved TATP though the New York Times reported the plotters intended to use HMTD. The discovery of the plot resulted in baggage restrictions and a banning of all liquids. Passengers now found themselves having to stow often valuable laptops and cameras in the hold as checked-in luggage while at the same time giving up drinks, perfume, toothpaste and other items. In the immediate aftermath of the plot being uncovered, no hand luggage was allowed except for a very few essentials such as travel documents and wallets. Carry on luggage restrictions have relaxed a little though a liquid ban remains in force around the world for items larger than 100 ml.

Reaction to latest attack

The latest attack on board Northwest Airlines flight 253 has once again prompted a review of security. The US has already imposed baggage restrictions for aircraft flying into the country. In addition passengers are now being told they may not leave their seat in the last hour of flying nor use the toilet. Electronic items have also been barred from use in the final stage of the journey and a passenger may not cover themselves with a blanket or coat. Israel already employs some of these restrictions on its own airlines. A person attempting to leave their seat during the last hour of flight draws attention as it did the day after the attempted bombing on Christmas Day. A Nigerian, ironically on the same flight number to Detroit had spent an hour in the toilet and created concern enough for stewards to break down the door. He was said to be abusive and later handed to authorities after the plane landed, though as it turned out he was simply a "sick passenger" according to a U.S. official who spoke shortly afterwards to Fox News [Telegraph].

After Abdulmutallab's apparent ease at taking high explosives on board a passenger jet, Dutch airport authorities want the EU to make passenger scanners mandatory, arguing that they might have stopped a man who tried to blow up a US airliner. Amsterdam's Schiphol Airport has 17 of the microwave security scanners, but their use remains voluntary because of continuing privacy concerns. Schiphol now has software to scan the image, an airport spokeswoman said, "so we think the privacy issue is solved".

Body scanners

However some have raised concerns over the safety of the scanners themselves. According to one senior radiologist the scanners could expose passengers to potentially dangerous levels of radiation. The machines are designed to "strip search" passengers by using low-level X-Rays, which produce an image of their bodies, revealing whether they are secretly carrying weapons, explosives or illegal drugs. However, Dr Sarah Burnett, who works as an independent radiologist in London, says the scanners may not be safe for certain people, particularly children and women in the early stages of pregnancy. "It is illegal to expose people to any level of radiation without medical justification," said Dr Burnett, who raised her concerns after being asked to undergo a full-body scan at Luton Airport a year ago. "So how is it that the Government is allowed to irradiate us willy-nilly at airports?" she asks. "I am particularly concerned about the potential effects on women in their first trimester of pregnancy. That is when the risks of the baby developing genetic abnormalities are highest because radiation exposure can damage the body's reproductive DNA."

Called the Rapiscan Secure 1000, the device looks like a large filing cabinet and fires a low-energy X-Ray beam over the body. According to Rapiscan Systems, the California-based company which makes the machines, each scan generates only three microrems of radiation - compared to 10,000 in a chest X-Ray. The firm claims this is no higher than the amount that the body is normally exposed to every five minutes from "natural" radiation in the atmosphere. The company also says that frequent flyers would need to have at least 5,000 scans a year before there would be any health threat.

There remains some caution amongst some scientists as to the use of this relatively new technology. There are two main types of machine utilized. One is a Backscatter X-Ray device and the other is a Millimeter wave scanner. Both devices raise privacy issues. And there are disputed views as to their effect on health. In contrast to the traditional X-ray machine, which detects hard and soft materials by the variation in transmission through the target, backscatter X-ray is a newer imaging system which detects the radiation which comes back from the target. It has potential applications in almost every situation in which non-destructive examination is required, but only one side is available for examination. Some people are concerned with exposure to radiation emitted by backscatter X-rays. At airports, lead vests are not used and people fear being exposed to "dangerous level of radiation if they get backscattered too often." The Health Physics Society (HPS) reports that a person undergoing a backscatter scan receives approximately 0.005 millirems of radiation while the American Science and Engineering Inc. reports 0.009 millirems. According to U.S. regulatory agencies, "1 millirem per year is a negligible dose of radiation, and 25 millirem per year from a single source is the upper limit of safe radiation exposure."

The other type of scanning device is the millimeter wave scanner which employs extremely high frequency waves in the terahertz range, which lie at the far end of the infrared band, just before the start of the microwave band. Although terahertz photons are not energetic enough to break chemical bonds or ionise atoms or molecules, the chief reasons why higher energy photons such as x-rays and UV rays are so bad for us, there may be other mechanisms at work. The evidence that terahertz radiation damages biological systems is mixed. "Some studies reported significant genetic damage while others, although similar, showed none," says Boian Alexandrov at the Center for Nonlinear Studies at Los Alamos National Laboratory in New Mexico. Alexandrov and his scientific colleagues have created a model to investigate how THz fields interact with double-stranded DNA. They say that although the forces generated are tiny, resonant effects allow THz waves to unzip double-stranded DNA, creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication. Of course, terahertz waves are a natural part of the environment, just like visible and infrared light. But a new generation of devices are set to appear that not only record terahertz waves but also bombard us with them. If our exposure is set to increase, the question that urgently needs answering is what level of terahertz exposure is safe.

The scanners may find some contraband and weapons on individuals but it is doubtful it would have picked up the reported 50 grams of explosive molded to Abdulmutallab's body and sewn into the crutch area of his underwear. Drug smugglers have often resorted to swallowing multiple packets of drugs in order to pass easily through customs. If terrorists employed such methods, even body scanners would fail to detect the presence of explosives. Unfortunately, increased security can never be 100% effective. It can also be a nuisance, a hindrance to free movement and even, as suggested by some, a possible threat to health. There is also a financial cost involved. A traditional archway metal detector can cost up to $15,000 dollars. The more intensive whole-body scanners cost more than $100,000. With airport operators strapped for cash the implementation of such equipment may not come soon.

However the stocks of the companies who make the devices has seen a shift in recent days. Some smaller companies such as ICX Technologies and OSI Systems, worth only a few hundred million dollars to begin with, rose 10% or more on Monday. Larger players like Smiths Group and L-3 Communications have also benefited, with their machinery already in trials in airports around the world.

The question remains whether the explosives could have destroyed the plane. Missile and explosives expert Herman Schöyer, formerly with European space agency ESA, says not. "Most explosive materials have be placed in high-pressure containers for an explosion to occur. That was not the case here," Schöyer says. Even if the man had not been subdued immediately, Schöyer doesn't believe the fire would have been much larger. "Eighty grammes of PETN burns away within a second and the seats are fire resistant. Although quenching was of course necessary." Abdulmutallab could have made a significant hole in the side of the plane had he placed the PETN in a box against a wall, according to Schöyer. "Depending on the altitude of the aircraft and the difference between air pressure inside and outside the plane, this could have been fatal to the passengers. But if someone, like this man, ignites loose powder, it has little effect."

The new technology may not have even caught Abdulmutallab as he passed through Schiphol airport. "There is no 100% guarantee we would have caught him," Schiphol Group COO Ad Rutten told Reuters. Jane's Aviation analyst Chris Yates said that several procedures need to be put in place rather than just one technology. "Absolutely without a shadow of doubt this is a good thing," he said referring to the new body scanners. "But one solution will not address every vulnerability. It needs to be a set of solutions," Yates said. The terrorist has, it's often said, only to be lucky once, we have to be lucky all the time. This time we were lucky, though the incident will have long running implications for airline security [NYT].

tvnewswatch, Beijing, China

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