Scientific Imaging of Cell Phone and Wi-Fi Radiation Absorption in the Human Body
Cell phones and other wireless devices emit microwaves, a type of non-ionizing radiation also referred to as radiofrequency radiation. When we are exposed to this radiation, it penetrates and is absorbed by our tissues. When government guidelines were developed 30 years ago, scientists had little understanding of just how deeply the radiation penetrates the body, and what anatomical features would absorb significant amounts of radiation. State of the art technology now allows scientists to model how this radiation interacts with human tissues.
“the average radio frequency radiation energy deposition for children exposed to mobile phone RF is two times higher in the brain and 10 times higher in the bone marrow of the skull, compared with mobile phone use by adults”.
(Read it on page 44 of the IARC Monograph on Radiofrequency Fields)
On this page we share scientific imaging developed using anatomically based models to calculate how radiofrequency radiation from various devices penetrates and is absorbed by our bodies. Environmental Health Trust works to support scientific researchers who are doing this critical work.
Fact: Children are more exposed to cell phone radiation.
These animations show how deeply cell phone radiation is absorbed in a model of a 6 year old brain. The highest absorption is in the area closest to the phone.
Multiple research studies over the last two decades clearly show that a child’s brain absorbs radiation differently from an adult, with regions deeper in the child’s head absorbing higher doses than adults.
- Children have smaller heads with a shorter distance to brain centers.
- Children have smaller ears so that a cell phone on the ear will be closer to the skull than a cell phone placed to an adult’s larger ear (which acts as a spacer between the brain and phone).
- Children’s skulls are thinner allowing radiation to penetrate deeper past the skull.
- Children’s brains contain more fluid and less fat and more readily absorb microwave radiation (myelination of the brain is incomplete).
- Compared with an adult skull, the immature skull contains more water, so the skull and adjacent tissues are more similar in a child than in an adult. This means that less radiation is reflected at the interfaces (greater reflection occurs at interfaces of less similar substances), so again, more radiation enters a child’s brain.
Cell phone radiation penetrates into the brain .The animations of cell phone radiation into the brain are derived from the work of researchers Álvaro Augusto Almeida de Salles and Claudio Claudio Enrique Fernandez Rodriguez, engineers from the Electrical Engineering Department of the Federal University of Rio Grande do Sul, UFRGS Porto Alegre, RS, Brazil (as seen in the video). The simulations were conducted using a sophisticated computer system that the U.S. Food and Drug Administration (FDA) currently uses to evaluate medical devices- but not cell phones.
Tablets: How far does the radiation from a tablet penetrate into a child’s brain?
A recent paper shows the WiFi radiation absorption into a child’s head from a tablet at roughly 6 inches (specifically 150mm away from the face) from a tablet. Please take a look at the image below. The highest radiation levels are shown in white yellow and red.
- A tablet, including the antenna and the box, was simulated at 2.45 GHz assuming 30 mW normalized radiated power and the distance between the eye lens of the head models and the tablet was 150 mm. The SAR in the head models is estimated in each situation of exposure.
- This research shows higher values in the anatomically correct child model. “For 1 g psSAR the child heterogeneous model shows higher values in comparison to the SAM model.”
In short, the current regulations for bringing these devices onto the market should be updated to include radiation modeling that considers children’s unique characteristics. The radiation from a tablet penetrates into a children’s skull, eyes and brain when positioned in front of the face as children typically do during use. Additionally, the penetration into the abdomen and chest when a tablet is rested on the lap is critical research that still needs to be done in order to fully understand exposures.
Laptops: What areas of the body receive Wi-fi radiation from a laptop?
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Download the BioEM2015 Poster Laptop psSAR.pdf
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Wearables: Google Glass and Bluetooth Radiation
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Google Glass and Bluetooth emit radiofrequency radiation, in close proximity to the head and brain. One concern that researchers have raised is that body worn technology results in ongoing exposures to vulnerable areas. The eye and brain are the most vulnerable areas.
These SAR simulations with laptops and with wearable devices (such as the Google glass) were presented in the 2015 BioEM conference in California. This research used anatomically correct models to understand how the radiation was absorbed into human tissues.
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Please take a look at the published paper Specific Absorption Rate SAR in the head of Google glasses and Bluetooth users doc. This paper was presented in the 2014 IEEE Latincom Conference, held in Cartagena, Colombia, in Nov/2014. Read Specific absorption rate (SAR) in the head of Google glasses and Bluetooth user’s online at the journal IEEE here. This paper simulated the Specific Absorption Rate (SAR) for three different head models and compared results with international recommendations. The simulations were performed using the finite difference time domain (FDTD) method and the frequency used to feed the antennas was 2.45 GHz.
Pregnancy: How much radiation does a fetus absorb when a cell phone is near a pregnant woman’s abdomen?
One of their findings was that occupational exposure limits are too high for pregnant women and that some product standards (induction cooker hobs) must be revised, since they may lead to excessive SAR levels in the foetus. In Quantification of RF-Exposure of the Fetus Using Anatomical CAD-Models in Three Different Gestational Stages by Cabot et al (2014) researchers found that for plane wave exposure at occupational levels, the whole body SAR in the fetus can exceed the basic restrictions for the general population by at least 1.8 dB, and in the near-field of professional devices, the 10 g SAR can be non-compliant with the product standard for the general public by > 3.5 dB.
What is the “anatomically correct” Virtual Family?
Click on image to enlargeThe Virtual Family models – Ella, Duke, Billie, and Thelonious are computerized whole-body anatomical human models. The human body consists of different tissues from the bones to the skin to veins and organs. Radiation moves through each of these organs and tissues at a different pace because of the density and unique composition of each tissue. The Virtual Family has approximately 300 different organs and tissues. They were originally developed for electromagnetic exposure evaluations. The Virtual Family models are DUKE: 34-year-old male, ELLA: 26-year-old female, BILLIE: 11-year-old female and THELONIOUS: 6-year-old male.
The Virtual Family V2.0 models consist of simplified CAD files optimized for finite-element modeling in third-party commercial platforms such as ANSYS and CST. For the purpose of simplification, the approximately 300 organs and tissues of version 3.0 are combined into 22 high-resolution tissue groups.
The family has been expanded into the Virtual Population with several other models such as pregnant women, people of larger stature and teenagers.
Meet The Scientists Behind the Research
Dr. Om Gandhi
Dr. Om Gandhi, a pioneering researcher in EMF exposure, explains why the recent rapid increases in wireless devices have made existing US EMF exposure ‘guidelines’ dangerously outdated.
Professor Alvaro Augusto de Salles
On Reducing Cell Phone Risks
Professor Alvaro Augusto de Salles
Antennas and Health Risks