Thursday, December 31, 2009
Body scanners have revolutionized the practice of medicine since they were first introduced into routine clinical practice in 1974. Companies are coming out with faster scanners that take more comprehensive pictures. A millimeter wave scanner is a whole body imaging device used for airport security screening. It is one of two common technology used for body imaging; the other is the backscatter X-ray. In comparison to x-rays from medical applications, the backscattered x-rays are considered high energy. A "high energy x-ray beam" moves rapidly over the person's form and a high resolution image of the person's nude body. Here is the question, Are They Safe? There are no known “safe” doses of radiation in terms of radiation-induced cancer risk.
CT (computed tomography) scanners is a rotating x-ray device to create hundreds of individual images reconstructed into a three dimensional view of the body by computers. Many readers have heard of these scans. MRI technology also produces fast scans. MRI scanners also provide sharper, clearer images of the body. They help physicians detect cancerous tumors, debilitating diseases and other ailments at earlier stages of development. You may have heard the term ‘3T,’ the “T” in “3T” refers to “tesla” a unit used to measure the magnetic strength of the MRI scanners. Current CT scanners are able to image the entire human body within seconds, and provide high definition images with an incredibly detailed view of organs and tissues. Scanner use low doses of radiation, but many older machines rely on higher doses. Scanners are for particular procedures they are not standardized, and a wide variance in doses can be delivered to the subjects. Security scanners use millimeter waves, these are the scanners used in Airports. As these complex and powerful diagnostic imaging machines continued to grow, so will the potential risk of radiation-induced cancers from radiation exposure administered during body scans at Airport Security.
A number of private radiology imaging centers offer “body scans” for clinically healthy people who are interested in having their internal organs examined for any early signs of diseases. Physicians have become so dependent on these machines that they request a scan for many visits. The same theory has turned to airport security; a full body scan will be requested before boarding a plane, screening the healthy with low dosages of radiation. Medical implants such as cardiac and neural stimulation leads could be affected by the electrical field produced by a pulse generator and significantly alter (either increase or decrease) the waveform of a pacemakers pulse.
Airport Full Body Scanners work by Millimeter wave technology. This band has a wavelength of ten to one millimetre, giving it the name millimeter band or millimetre wave. These waves are considered Extremely High Frequency, the highest radio frequency band. EHF runs the range of frequencies from 30 to 300 gigahertz, they are also sometimes abbreviated MMW or mmW. These bands are also known as terahertz radiation. Terahertz radiation may interfere directly with DNA. The force generated is small but the waves disturb double-stranded DNA, creating bubbles in the double strand. These scanners provide exceptionally clear views of subjects by combining data from multiple X-ray images, but the increased exposure to X-rays, which cause mutations in DNA that, can lead to cancer. X-rays are considered ionizing (penetrating) radiation, ionizing radiation in any dose causes genetic mutations, which set all living cells exposed on the path to cancer. Cancers associated with high dose exposure include leukemia, breast, bladder, colon, liver, lung, esophagus, ovarian, multiple myeloma, prostate, nasal cavity/sinuses, pharyngeal, laryngeal, pancreatic and stomach cancers. Clothing and organic materials are translucent in most mm-wave bands. Perfect for detecting objects on subjects at airports. The scanner does allow the screener to see detailed images of body parts, as I explained with CT and MRI scanners.
Whole body scans of healthy people may be creating more problems than they solve by exposing healthy people to radiation. The risk for radiation over exposure may be small for single subject, but the number subject exposed to airport body scans will increase they risk by the millions. A normal CT scan of the chest is the equivalent of about 100 chest X-rays. Some scanners are equivalent of 440 conventional X-rays. The traditional X-ray machine detects hard and soft materials by the variation in transmission through the target. The backscatter X-ray detects the radiation that reflects back from the target. Several studies have suggested that people have been unnecessarily exposed to radiation from CTs or have received excessive amounts of radiation. A person undergoing a backscatter scan receives approximately 0.005 – 0.009 millirems of radiation. 1 mrem per year is a negligible dose of radiation, and 25 mrem per year from a single source is the upper limit of safe radiation exposure. Widespread overuse of body scanners and variations in radiation caused by different machines could subject many to radiation doses that could ultimately lead to thousands of new cancer cases and deaths.
It’s Gonna Be BEDLAM!