GSM & HEALTH
Technology grows very rapidly. As a result of this huge development, everyday, a new technology comes to our life and we have been more depending on Electromagnetic (EM) Fields. EM radiation is produced by conducting wires, all devices used in working places and houses (refrigerator, washing machine, dish washer, hair dryer, electric razor, etc), cell phones, microwave owens, etc.
In all over the world and in TURKEY, scientists still argue whether EM radiation effects biological systems or not, thus studies on possible effects are still going on.
What is Radiation?
What is Radiation?
Electromagnetic radiation can be characterized as waves of electrical and magnetic energy radiating into space from a transmitting source with a speed of light. These waves are created by the acceleration of electrical charges. For example, the movement of charge in a transmitting radio antenna, i.e. the alternating current, generates electromagnetic waves that radiate away from the antenna and can be intercepted by a receiving antenna. Radiation sources are characterized in two groups according to whether they cause ionization in the tissue or not.
Ionizing Radiation(f > 1016 Hz):
Ionizing Radiation includes alpha rays, beta rays, gamma rays, X-rays, neutrons, high-speed electrons, high-speed protons, and other atomic particles; but such term does not include sound or radio waves, or visible light, or infrared or ultraviolet light. When this type of radiation is absorbed by the tissue it causes ionization.
Nonionizing Radiation (EM Radiation):
Nonionizing Radiation is a general term for both radiations and fields that form part of the electromagnetic spectrum having insufficient radiated energy to produce ionization in the medium through which it passes. Nonionizing radiation includes electric and magnetic fields, electromagnetic fields and radiation in the frequency range 0-300 GHz, optical radiations (ultraviolet, visible light, and infrared) and ultrasound (frequencies above 16 kHz).
EM Field Sources
EM Field Sources
The human body has its own magnetic field strength in the order of 10-5 G - 10-9 G. The comparison of human body and geomagnetic field strength (10-5 G) shows that body is harmonious with the natural magnetic field. However, the products of technology, such as mobile phone, computer, TV, electrical devices, radar, etc, destroy this harmonization although they facilitate our life. Since, EM fields produced by these devices are much greater than body's and natural field's.
EM Field Sources Frequency Distance Elektric Field Magnetic Field Earth - In Normal Weather 120-150 V/m (3-10)x10-5 G Eye 0-10 Hz (ELF) - - 10-7 G Hearth Muscle 0-40 Hz (ELF) - - 2 x10-6 G Brain Waves (Excited) 0-100 Hz (ELF) - - 10-9 G Dish Washer 50-60 Hz (ELF) Near 60 V/m 10-100 mG Cooker 50-60 Hz (ELF) 20 cm. Away - 50 mG Hair Dryer 50-60 Hz (ELF) Near 40 V/m 10-25 G TV and Computer Monitor 50-60 Hz (ELF) Near - 1-5 G Electric Razor 50-60 Hz (ELF) Near - 5-10 G Fluorescent Lamp 50-60 Hz (ELF) On the Ceiling - 5-10 G Iron 50-60 Hz (ELF) Near - 10-100 mG Toaster 50-60 Hz (ELF) Near - 100 mG - 1 G Power Lines 50-60 Hz (ELF) Near 8000 V/m - Refrigirator 50-60 Hz (ELF) Near 60 V/m 1-10 mG
ELF: Extremely Low Frequency 0-104 Hz
RF / MW Alan Kaynakları
Everyday the number of base stations increases with respect to the increase in the usage of mobile phones. This much increase causes scientists to investigate the health effects of RF /MW field sources such as microwave owens, mobile phones, diathermy equipment. Mobile phones and base stations work in RF / MW range, where RF 104 - 109 Hz , MW 108 - 1012 Hz and mobile phones : 108 - 109 Hz (900 MHz = 9x108 Hz, 1800 MHz = 1.8x109 Hz).
RF: Radio Frequency, 104 - 109 Hz
MW:Micro Wave, 108-1012 Hz
Mobile phone base stations are low power radio transmitters with antennas mounted on either free-standing towers or on buildings. These antennas emit RF beams that are typically very narrow in the vertical direction but quite broad in the horizontal direction. Because of the narrow vertical spread of the beam, the RF field intensity at the ground directly below antenna is low. As the distance between the object and the antenna increases, the electric and magnetic field strengths will be reduced in the second order of distance.
Biological Effects of EM Field
Biological Effects of EM Field
Biological effects can be divided into two categories: ELF field effects and RF /MW field effects. ELF field effect’s concept origin from the devices used in homes and offices, power lines and transformers. RF/MW field effect’s concept origin from TV and radio transmitters, microwave owens, diathermy equipment, mobile phones and base stations.
Results of the studies done on people living near power lines:Studies on the effect of RF / MW radiation:
Changes in immune system response,
Changes in brain and central nervous system activities,
Changes in embryo,
Changes in genetic mechanism,
Increase in the statistics of depression, hallucination, headache,
Sleeping disorders by reducing synthesis of melatonin.
Most of these effects are related to causation of cancer. In 1975 Russia reported that E-field strength should be 1-5 kV/m, USA applied this value as 9 kV/m in 1982. USA National Academy of Sciences stated that the occurrence of leukemia among children living near power lines is 1.5 times greater than others.
RF / MW radiation is mostly absorbed by kneecap, metallic implant, lens of eye, and brain.
Microwave Hearing Effect:
According to the strength and the period of exposed radiation sound can be heard as buzzing, clinking. However, it has not been found that this is a permanent effect. With experimental and epidemiological studies, it is reported that if one uses a mobile telephone for a long time in a day, then he will hear sound as pulsed and buzzing.
Effect on the Permeability of BBB (Blood Brain Barrier):
The neurovascular construct commonly known as the blood-brain barrier (BBB) functions as a differential filter that permits the selective passage of material from blood to brain. It maintains the physiochemical environment of the brain within certain narrow limits which are essential for life. Many investigators have reported studies on the effect of microwave radiation on the blood-brain barrier of experimental animals with varied results. Several authors using both high and low levels of microwave exposures have shown microwave-induced increase in BBB permeability especially increases in antibiotics. It is said that this can be lead to the treatment of viruses placed in brain.
EM Fields having 10 W/m2 power densities causes effects on the nervous system. But, this value is above the maximum permissible limits given in the regulations of Minister of Transportation (for 900 MHz 4.5 W/m2 , for 1800 MHz 9,0 W/m2 ).
Changes in DNA Structure:
Increase in the damage of DNA structure was observed in 9 of 12 guinea pigs among, on the other hand decrease in the damage of DNA structure was observed in 5 of 9 guinea pigs among. So, experiments on this effect do not compensate each other.
In USA and England governmental and independent groups reported health effects of cell phones in their reports entitled "Mobile Phones, Base Stations and Human Health". These groups concluded "there is no human evidence of a risk of cancer resulting from exposure to radiations that arise from mobile phones. Furthermore, a biological study on possible effects on human prevention or progression, including work with experimental animals does not provide clear evidence of a risk."
Psychological and Behavioral Effects:
In both studies done by Mann & Röschke and Borberly, disorderness in sleeping was observed. In another experiment done by Wang & Lai, animals exposed to 2450 MHz having disability in learning, but this study has not repeated, yet. Also Wang & Lai has studied on long-term memory loss in the exposure to 2450 MHz and they have found positive results. All these studies done on 2450 MHz, but mobile phones work in 900 and 1800 MHz.
On people living near to power lines, it is observed an increase in the statistics of depression, hallucination, and headache.
Mobile phones' radiation effects are determined by SAR (Specific Absorption Rate). SAR (Specific Absorption Rate) is a measure of the amount of RF power absorbed in any part of the human body due to the use of equipment such as mobile phones or by human exposure close to other transmitting sources. Permissible exposure limits for SAR; 0,4 W/kg for occupational, 0,08 W/kg for public exposure.