menu

ProPublica: New Army Study Reassures Radiation From Airport Body Scanners Is Minor

ProPublica: New Army Study Reassures Radiation From Airport Body Scanners Is Minor
Advertising

X-ray body scanners that have adorned several airports raised health questions. Worried flyers can now relax as the radiation from the scanners has been proven not to cause cancer.

Valentina Park
  • 18 july 2011

new study of airport body scanners by U.S. Army scientists shows that the machines produce a low dose of radiation, supporting Transportation Security Administration claims that a screening is equivalent to the radiation a passenger gets in two minutes of flying.

The scanners, which use X-rays to check for objects hidden under clothing, have been the subject of controversy about how safe they are and whether they create a cancer risk for the traveling public. Although the study is unlikely to douse those concerns, one critic of the machines called it the most reliable test to date.

“These are the best measurements that have been done,” said Peter Rez, an Arizona State University physicist who in April signed a letter to the White House science adviser questioning previous tests. “Things have to be filled in, but it’s a step in the right direction.”

The study results obtained by ProPublica were presented at a Health Physics Societyconference in late June.

The TSA rolled out plans to put full-body scanners at nearly every security lane by 2014 in response to the attempted bombing of a Detroit-bound plane by a man who had explosives hidden is his underwear.

The agency uses two kinds of imagers. In the backscatter machine, a passenger stands between two large blue boxes and is scanned with a narrow X-ray beam that rapidly moves left to right and up and down the body. In the millimeter-wave machine, a passenger enters a chamber that looks like a round phone booth and is scanned with radio-frequency waves.

Although the safety of both machines has been questioned, most of the attention has centered on the backscatter machine because it uses ionizing radiation, which can damage cells and cause cancer.

To reassure travelers, the TSA asked the Army Public Health Command to conduct radiation surveys at airports around the country. The new study, paid for by the TSA and done at a TSA lab, was part of that work.

There is much debate in the field about how little — or whether any — radiation is safe.

According to the Army presentation, the average dose to the body was 3.8 microrems per screening, meaning that a person would have to go through the machine more than 5,000 times to exceed the annual dose limit recommended by the American National Standards Institute. By comparison, a chest X-ray produces about 10,000 microrems of radiation.

The test also provides new information about the dose to the skin and eyes, which has been a concern because low energy X-rays deliver a large portion of the radiation to shallow tissues. The Army testers measured the average dose to the lens of the eye at 6.7 microrems and the average skin dose at 11.3 microrems, both of which were extremely low compared to the accepted guidelines.

The study, however, does not make a conclusion about whether the machines are safe.

Some scientists have estimated that the routine use of the machines planned by the TSA could result in anywhere from a handful to a hundred additional cases of cancer over a lifetime. But even with long-term tests, it would be difficult to separate the scanner effects from other common sources of exposure, such as medical X-rays and cosmic radiation from flying at high altitudes.

The test is different from others that have been done because the Army used “optically stimulated luminescent” dosimeters — similar to the badges worn by nuclear workers — to measure the radiation.

In the past, the TSA has relied on tests conducted by the Food and Drug Administrationand Johns Hopkins University that used a radiation detector known as an ionization chamber. Rez and a group of scientists at the University of California, San Francisco argue that ion chambers are inadequate for the fast-moving, low-energy beam emitted by the backscatter machines.

An ion chamber is a device that measures radiation exposure by generating an electrical current. In contrast, an OSL dosimeter is a new type of badge that uses a crystal, which is then read with a light.

Usually, dosimeter badges aren’t adequate for a single scan because they need a high dose of radiation or an exposure over a long period of time to register a reading. Walking through a body scanner on the way to catch a plane would probably not produce a reading.

To overcome that problem, the Army used robots to run 93,000 screenings over two weeks. They simulated a 190-pound person by building a dummy out of water jugs arranged on a wooden frame.

Testers then placed 181 dosimeters in and around the system, according to an email ProPublica obtained from the Electronic Privacy Information Center, a civil liberties group in Washington, D.C., that sued the government to get scanner records under the Freedom of Information Act.

Rez said the study doesn’t address his concern about how much radiation a person would be exposed to if the machine breaks down and the beam stops on one spot on the body. It also didn’t stanch the calls from Rez and others to allow testing by outside scientists.

“From a public relations point of view,” Rez said, “it would have more clout if it was done by someone who can be seen as being independent of government.”

(Read original article here.)

[Written By Michael Grabell, Republished with kind permission from ProPublica]

ProPublica is an independent, Pulitzer prize-winning national newspaper where they focus on stories with “moral force.” Learn more about ProPublica.

 

Advertising
Trending

Banned Books Week Urges People To Seek Out Controversial Works

Syndicated
Arts & Culture Today

Small Urban Pavilions Create A Nature Refuge In East London

These relaxing micro shelters provide a haven amidst chaotic city environments

Travel Today

Travel Laundry Pouch Washes Your Clothes Wherever You Are

The Scrubba Wash Bag helps anyone wash their clothes easily and quickly with just a little water and soap

Trending

Get PSFK's Related Report: Future of Automotive

See All
Social Media Today

Swipe Up To Register To Vote On Snapchat

The social platform has partnered with TurboVote to help young people easily enroll in less than one minute

Children Today

Battle Card Game Promotes Childhood Vaccinations

An Australian doctor has developed a playful way to inform parents about immunization and entertain kids

Related Expert

Jessica Richman

Data, Citizen Science, Personalized Medicine

Fitness / Sport Today

Oakley And Intel’s Sunglasses Give You A Built-In Personal Trainer Wherever You Go

The sunglasses/earbuds hybrid tracks your performance and lets you know how well your workouts are going

Experiential Marketing Today

UNICEF’s ‘Time Machine’ Tells Stories With Data

An experiential installation at the UN General Assembly reminds us why every child matters

Design & Architecture Today

Watch The World’s Tallest Building Become An LED Display

Burj Khalifa gives a backstage look at how the transformation came to be

PSFK LABS REPORT

Future Of Automotive
Scenarios Driving The Digital Transformation Of An Industry
NEW

PSFK Op-Ed september 23, 2016

Productivity Expert: The Magic Of The Five-Hour Workday

Stephan Aarstol, Founder of Tower Paddle Boards, explains why the modern notion of office hours needs to evolve

PSFK Labs Today

Modern Workplace Culture: No More Fat Cats Or Kissing Ass

Samar Birwadker, CEO & Co-Founder of Good & Co, on designing shared organizational values to optimize employee happiness and success

Travel Today

Boeing Wants To Make Your Flight Better With Cloud And Star Projections

The manufacturer is trying to patent a projection system that would allow them to project images onto a plane's interior surfaces

Latin America Today

Colombians Teach Dance To Fund Students’ Education

Chocó to Dance is a platform that shows you how to replicate popular Latin dances to help create scholarships for local students

Work Today

Editorial Roundtable: What A People-First Workplace Must Prioritize First

Managed By Q, Soma, Workbar, Primary, AltSchool and thinkPARALLAX on why employee fulfillment is a journey and not a destination

Culture Today

Brand Engagement At The Gates Of The World’s Largest Open-Air Gallery

Tiger Beer and a neighborhood-minded nonprofit celebrate and promote New York's creative spirit by beautifying 100 security gates

PSFK LABS REPORT

Future Of Work
Cultivating The Next Generation Of Leaders
NEW

Technology Today

How Technology Can Save The World By Saving Time

PSFK attends the Social Good Summit 2016 to see how new tech is changing the world for the better

Advertising Today

Lancôme’s Newest Campaign Stars A Domestic Abuse Survivor

Rosie Batty is the new face of the Love Your Age series, and is using the platform to bring awareness to a prevalent and deadly problem

Travel Today

Marriott’s Gravity Room Installation Gives Travelers A New Perspective

The luxury hotel chain's #MGravityRoom invites visitors to snap and share pictures of its inverted set up

No search results found.