Airport Scanners: Damaging Dna Or Just Security Checks?

Airport security scanners have been a topic of concern for travellers, especially regarding their potential impact on human health. While the manufacturers of these scanners have assured the public of their safety, recent studies and incidents have raised doubts about their potential effects on DNA. The use of X-ray body scanners in airports, which emit ionizing radiation, has sparked particular concern. This type of radiation has the energy to knock electrons off atoms, creating free radicals that can damage DNA and increase cancer risk. Although the dose of radiation from airport X-ray machines is considered too low to cause significant harm, there are still questions about the long-term effects of exposure, especially for frequent travellers. Additionally, the controversial Rapiscan X-ray scanners, which produced detailed body images, were removed from airports due to privacy concerns, further highlighting the delicate balance between security and privacy in airport screening procedures.

X-ray scanners replaced by millimeter wave scanners

X-ray scanners have been replaced by millimeter-wave scanners in many airports around the world. This change has come about due to concerns over the safety of X-ray scanners, as well as privacy and security issues.

X-ray scanners use ionizing radiation to detect objects on or inside a person, including non-metal objects, which metal detectors cannot identify. However, the health risks posed by X-ray scanners have been widely debated, with some studies showing an increased incidence of cancer in those exposed to the radiation. As a result, several countries banned the use of X-ray scanners in airports, and in 2013, the US replaced them with millimeter-wave scanners.

Millimeter-wave scanners use non-ionizing electromagnetic radiation to detect objects, similar to that used in wireless data transmission. They work by directing millimeter waves at the subject and interpreting the reflected energy to create a 3D image, which is displayed on a remote monitor. These scanners do not generate ionizing radiation and are considered safer than X-ray scanners. However, there are still concerns about the potential health effects of millimeter waves, and the long-term effects of this type of radiation are still uncertain.

In addition to health concerns, privacy issues have also played a role in the replacement of X-ray scanners. X-ray scanners create detailed images of the person being scanned, which some critics have likened to virtual strip searches. Millimeter-wave scanners, on the other hand, create a generic outline of a person, with potential threat areas highlighted, addressing privacy concerns.

While millimeter-wave scanners address some of the issues associated with X-ray scanners, there are still questions about their effectiveness. Some studies have shown that these scanners have a high rate of false positives, with objects such as folds in clothing or sweat confusing the machine. There are also concerns about the potential for these scanners to capture and disseminate images, despite privacy protections in place.

Overall, the replacement of X-ray scanners with millimeter-wave scanners in airports is an ongoing process, with a focus on balancing security needs with health and privacy concerns. While millimeter-wave scanners are considered safer, further research is needed to fully understand their potential health impacts.

Terahertz waves can unzip double-stranded DNA

Terahertz waves, or submillimetre radiation, occupy a middle ground between microwaves and infrared light waves in the electromagnetic spectrum. They are non-ionising and do not penetrate the body as X-rays do, but they can pass through thin layers of materials such as clothing, paper, cardboard, wood, masonry, plastic and ceramics.

Terahertz waves are used in airport security scanners, which raise concerns about their impact on human health. While the exact number of cancer cases attributed to the use of airport scanners has been debated, there is evidence to suggest that terahertz waves can damage DNA.

A study by Boian S. Alexandrov et al. at the Center for Nonlinear Studies at Los Alamos National Laboratory in New Mexico found that terahertz waves could "unzip double-stranded DNA, creating bubbles that could significantly interfere with processes such as gene expression and DNA replication." This was supported by a previous study by a team of Russian scientists, who found that millimetre waves similar to those used by airport scanners induced "statistically significant changes" in DNA, RNA, and proteins in animals.

The study by Alexandrov et al. created mathematical models to predict how terahertz radiation would interact with double-stranded DNA. They found that although the forces generated are tiny, resonant effects allow the waves to unzip the DNA strands. This process creates bubbles in the double strand that could interfere with gene expression and DNA replication.

The researchers also explained why evidence of this damage has been difficult to gather. Ordinary resonant effects are not powerful enough to cause this kind of damage, but nonlinear resonances can. These nonlinear instabilities are much less likely to form, which is why the character of terahertz genotoxic effects is probabilistic rather than deterministic.

The potential health risks of terahertz waves are concerning, especially as a new generation of cameras is being developed that will not only record terahertz waves but also emit them. With increasing exposure to these waves, determining a safe level of terahertz exposure is crucial.

The impact of terahertz radiation on fertility and fetal development

Terahertz radiation has been shown to have a detrimental impact on fertility and fetal development.

Impact on Fertility

Terahertz radiation, even at low levels, can pose a significant risk to male reproductive health. A study on mice revealed that exposure to this type of radiation caused an increase in white matter in the testicles, indicating the development of inflammation. Furthermore, genetic changes were observed that could impair sperm function and fertility. However, the effects were temporary, and the mice's bodies were able to recover within 24 hours. The long-term consequences of repeated exposure are still uncertain and require further research.

Impact on Fetal Development

Terahertz radiation has the potential to harm fetal development, particularly during the early stages of pregnancy. In utero exposure to radiation can lead to congenital malformations, growth retardation, and an increased risk of cancer in childhood. The threshold for potential prenatal radiation effects is approximately 0.10 to 0.20 Gy for a fetus under 16 weeks of gestation and increases to 0.50 to 0.70 Gy after 16 weeks. Exposure to radiation during the first trimester is associated with an increased risk of severe malformations and mental retardation. As the embryo grows, the risk decreases, but exposure during the second and third trimesters can still lead to malformations, growth retardation, mental retardation, cataracts, sterility, and malignancy.

The amount of radiation exposure from airport scanners

Airport security scanners use either backscatter X-ray or millimeter wave technology. Backscatter X-ray scanners emit ionizing radiation, which has the potential to cause biological damage by creating free radicals that can damage DNA and increase cancer risk. However, the dose of ionizing radiation from airport X-ray machines is not high enough to cause significant harm. The radiation exposure from a single airport X-ray scan is roughly 0.1 microsieverts, which is 1000 times less than the radiation from a chest X-ray, which is about 100 microsieverts.

Millimeter-wave scanners, on the other hand, emit non-ionizing radiation in the form of low-level radio waves. These scanners do not use X-rays and do not contribute to a person's ionizing radiation dose. The energy waves emitted by millimeter-wave scanners are extremely low, delivering a fraction of the energy of a cell phone. The Transportation Security Administration (TSA) in the United States asserts that millimeter-wave technology is safe and does not have any known adverse health effects.

Despite these assurances, some scientists have raised concerns about the potential health impact of millimeter waves. A study conducted at the Los Alamos National Laboratory in New Mexico found that terahertz waves produced by millimeter-wave scanners could "unzip double-stranded DNA, creating bubbles that could significantly interfere with processes such as gene expression and DNA replication." This has sparked concerns about the impact of such radiation on fertility, fetal development, and cancer risk.

In response to these concerns, the TSA has implemented privacy measures for passengers, such as blurring faces and installing software to make the scanned images less revealing. Additionally, the TSA has made it impossible for scanners deployed in airports to save or export images, addressing concerns about the improper storage and dissemination of scanned images.

While the debate about the safety of airport scanners continues, it is important to note that the amount of radiation exposure from airport scanners is generally considered to be low and not a significant health risk. However, for individuals who are particularly concerned about radiation exposure, opting out of the scanner and requesting a pat-down instead is always an option, although it may require some extra time at the security checkpoint.

The difference between ionizing and non-ionizing radiation

Ionizing radiation is a form of energy that acts by removing electrons from atoms and molecules of materials. These materials include air, water, and living tissue. Ionizing radiation can travel unseen and pass through these materials. Overexposure and unprotected exposure to ionizing radiation can result in cellular damage caused by the interaction of directly ionizing and indirectly ionizing particles with the atoms and molecules of tissue.

Non-ionizing radiation, on the other hand, does not have enough energy to remove electrons. It is a series of energy waves composed of oscillating electric and magnetic fields traveling at the speed of light. Non-ionizing radiation includes ultraviolet (UV), visible light, infrared (IR), microwave (MW), radio frequency (RF), and extremely low frequency (ELF). While you are exposed to low levels of non-ionizing radiation every day, intense exposure may result in damage to tissue due to heat.

The difference between the two types of radiation lies in their energy levels and their ability to remove electrons from atoms and molecules. Ionizing radiation has higher energy levels and can remove electrons, while non-ionizing radiation does not have enough energy to remove electrons.

Now, coming to the topic of airport security scanners and DNA damage, there have been concerns that airport body scanners, which use X-ray or millimeter wave technology, may alter human DNA and cause cancer. In 2011, the European Union banned the use of X-ray body scanners in airports due to health and safety concerns, including potential DNA damage.

According to a study by Boian S. Alexandrov et al. at the Center for Nonlinear Studies at Los Alamos National Laboratory, millimeter waves generated by these scanners can "unzip double-stranded DNA, creating bubbles that could significantly interfere with processes such as gene expression and DNA replication." This has raised serious concerns about the impact of such radiation on fertility, fetal development, and cancer.

However, the Transportation Safety Administration (TSA) in the United States insists that millimeter wave scanners "use non-ionizing radio-frequency energy with no known adverse health effects." The debate about the safety of airport security scanners continues, with some arguing that more research is needed to fully understand the potential health effects of this technology.

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