The facts about Body Scanners
Both types of body scanners come with inherent dangers. While there are some obvious dangers such as exposure to ionizing radiation, many facts are still unknown about this technology. Independent testing and information has been limited due to the refusal of the TSA to release information, citing national security concerns. In summary, here is some important information to consider when choosing to use the scanner or opt-out.
This machine emits high energy microwave energy called terahertz photons (5) in order to create an image of the human body with clothing removed. In one study (4) it was shown that terahertz waves terahertz waves could "...unzip double-stranded DNA, creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication." In other words, there is high potential for damage to human DNA when exposed to the energy from these machines. There are no known studies that show the cumulative impact of exposure to this radiation.
The ionizing radiation used from the backscatter is the same radiation as one would receive from a medical x-ray. Obviously, the health concerns of x-ray radiation are understood much more clearly than from the microwave radiation of the Millimeter Wave. Radiation effects are cumulative, and exposure to ionizing radiation carries an increased risk of cancer. A letter from Department of Biochemistry and Biophysics of the University of California San Francisco 6 brought up many concerns about the machines.
Several excerpts from the letter are important to be aware of. Regarding the radiation dose: "The majority of their energy is delivered to the skin and the underlying tissue. Thus, while the dose would be safe if distributed throughout the volume of the entire body, the dose to the skin may be dangerously high."
"It appears that real independent safety data do not exist."
It is obvious that there are many unknown implications using this technology. In addition, since these technologies are not classified as medical devices like would be used in the healthcare setting, they do not require trained radiologists to operate. The turnover of screeners is very high, and the exact training level of each person cannot be determined by a traveler. Would you allow yourself to be x-rayed in your doctor’s office by the receptionist?