A heated phone can cause cancer


Microwave ovens

The microwave uses high-frequency radiation with frequencies of 2.45 gigahertz to heat food. Due to the rapid polarity reversal of the electromagnetic fields, the water molecules in the food begin to vibrate and produce heat in the process. According to the BfS, slight leakage radiation can occur at the cracks in the door with some devices, but “at the usual locations in the vicinity of the microwave devices” the radiation should still be 1000 times below the valid limit value.


In mobile telecommunications, the radiation comes from two different sources: the cell phones and the base stations, which are responsible for the transmission and forwarding of the data.

Cell phones

Cell phones only emit relatively weak high-frequency radiation, their maximum power is 0.5 to two watts, their frequencies between 905 to 959 MHz (GSM-900, D-Netz) and 1710 to 1880 MHz (DCS-1800, E-Netz) . As a rule, the data is now transmitted digitally with the help of frequency-modulated and pulsed waves. Although the strength of the electromagnetic field decreases rapidly with the distance to the device, it is sufficient to penetrate a few centimeters into the head in the typical telephone position with the handset pressed directly to the ear. Those who make calls with a “hands-free” headset, where only microphones and headphones are placed directly on the skull, but the actual device is on the belt or on the desk, receives significantly less radiation.

Transmission systems

The base stations of the various mobile phone providers cover the densely populated metropolitan areas in particular with an increasingly fine-meshed network. At intervals of sometimes only a hundred meters, they send and receive the countless data packets that are transported via the pulses of electromagnetic radiation. The transmission power of the base stations is between five and 40 watts, mostly they are mounted on buildings or towers.

Since they scatter their radiation broadly in the horizontal direction, but are closely focused in their height, the load in and on the building directly below such a transmitter station is usually rather low. The typical values ​​for apartments in the vicinity of base stations are 20 µW / m2, a fraction of a thousandth of the applicable limit value. Often the health-endangering area of ​​two to five meters is also fenced in directly around the antenna.

Radar systems

The radiation emitted by radar systems at airports, for example, has a frequency of around 10 gigahertz. Since the depth of penetration of the waves into a body decreases with increasing frequency, the radar waves only penetrate a maximum of one millimeter into the skin. The field effects in the vicinity of the radar systems are usually low in the publicly accessible areas, since the main energy is not radiated onto the ground but into the air. Conventional traffic radar devices that are used on ships and in road traffic are - according to the Federal Office for Radiation Protection (BfS) - harmless to health even at a short distance of a few meters.

TV channel

Transmission antennas of television transmitters work in the frequency range of 174 - 216 megahertz (VHF band) and 470 - 890 megahertz (UHF band). For outputs of 300 kilowatts to five megawatts, the limit values ​​of two watts per square meter are complied with at a distance of 75 meters or more for UHF and 150 meters or more for VHF systems. As a rule, compliance with these values ​​is checked regularly when building a new system as well as with the existing transmission masts.

Radio station

Depending on the transmission frequency, the oscillation speed of the electromagnetic radiation varies between 1.4 megahertz (medium wave), six to ten megahertz (short wave) and 88-108 megahertz (VHF). The power of the transmitters also depends on the transmission frequency: VHF transmitters only have a relatively low output of a maximum of 100 watts, while medium-wave transmitters, on the other hand, still have 1.8 megawatts. According to the BfS, the applicable limit values ​​are reached at a distance of 220 to 350 meters from the antenna for all transmission systems.

In Germany, the Regulatory Authority for Telecommunications and Post (RegTP) has been monitoring compliance with the limit values ​​applicable to the respective antennas nationwide at periodic four-year intervals since 1992. The monitoring is intended to ensure that with the installation of more and more transmitter systems, the amounts of radiation do not at some point concentrate in such a way that the maximum permissible values ​​are exceeded.

Status: 08/26/2000