Harmful Effects of Mobile Phone Tower Radiations on Muscle and Bone Tissues of Human Body at Frequencies 800, 900, 1800 and 2450 MHz

The transmitted waves from the mobile phone tower were exposed to the human body and were penetrated into the body where the field was reduced exponentially with depth. In this paper penetration of high frequency electromagnetic waves emitted from a mobile phone tower into human muscle and bone tissues were studied. As the reduction in field was due to absorption of power, specific absorption rate was calculated at frequencies 800,900, 1800 and 2450 MHz and effective radiated power of 20 Watts.


. . . Introduction
So for bio-effects of static and extremely low frequency (ELF) fields have been dealt with. ELF fields are mostly natural and some fields are due to home appliances or factory power lines. The higher frequency field is mostly man made and at various places, sources produce fields of varying intensity. The main source of higher frequency fields is used in communication system i.e. Radio, T.V. microwave transmission and mobile phone communication system. They produce high frequency fields near transmission towers. People living around these towers might be effected because of these fields. At the same time users of receivers may be effected because of field resonance and concentration near them. Interaction of radio frequency fields with human body tissues is a complex function of various parameters. Radio waves in free space are characterized by the frequency, electric field (E) and magnetic field (H) field intensity, their polarization and direction. However, only fields inside the biological bodies and the tissues can interact with them, so it is necessary to determine these electric and magnetic fields for any general quantification and meaningful of biological data [1].
Most of the People are not conscious of mobile phone tower radiations which are very harmful due to electromagnetic radiation exposure. People living near cell tower receive strong signal strength but at the expense of health. It was found that the effective isotropic radiated power from base station antenna is not exceed unity [2].
The electromagnetic field (EMF) can be resolved into four parts, the electric and magnetic fields interact only with each other, the electric and magnetic fields are generated by electric charges, the electric and magnetic fields produce forces on electric charges which move in free space. A particle at rest feels only the force due to the electric field.
The measured rate at which energy is absorbed by the human body when exposed to a radio frequency (RF) electromagnetic field (EMF) is specific absorption rate (SAR). It is also defined as the power absorbed by the tissue per unit mass and is measured in watts per kilogram (W/kg). SAR is usually averaged either over the whole body or over a body tissue. The SAR is determined at the highest certified power level, the actual SAR level of the device while operating can be well below the maximum value. If we measure the specific absorption rate then mobile phone handset should be placed at the head in a talk position. The specific absorption rate value is then measured at the highest location of absorption rate in the entire head, which the mobile phone handset is often as close to their antenna as possible [3]. SAR values increase with the increase of conductivities of human body tissues and decreases with the increase of relative permittivity of human body tissues. Specific absorption rate describes the possible biological effects of RF fields. The high energy radio frequency field exposure causes thermal effects in biological tissues and generates high SAR values. This is called non-thermal effect.
The effect of dielectric values of the human body on the SAR is frequency dependent and orientation of the human body [4]. The maximum increase in temperature of human head tissue is due to specific absorption rate (SAR). At high power density levels, thermal effects occur, some of which can be attributed to heat induced stress mechanisms. The less understood non-thermal effects occur at low radio frequency/microwave power density levels and are not accompanied by any body temperature rise [5]. The effect of mobile phone radiation on human health is the subject of recent interest and study, as a result of the enormous increase in mobile phone usage throughout the world [6] Mobile phones use electromagnetic radiation in the microwave range. Other digital wireless systems, such as data communication networks, produce similar radiation.
Many scientific studies have investigated possible health symptoms of mobile phone radiation. These studies are occasionally reviewed by some scientific committees to assess overall risks. A recent assessment was published in 2007 by the European Commission Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) [7].
In India there are nearly 3.75 lakh mobile phone towers and to meet the communication demand, the number will increase to 4.25 lakh towers by 2010 [8]. In many countries, over half the population use mobile phones and the market is growing rapidly. At the end of 2014, there is an estimated 6.9 billion subscriptions globally [9].

. . . Calculations of Penetrated Electric Field and Specific Absorption Rate (SAR)
If we consider a mobile phone as a point source, the radiation is emitted around the mobile phone as spherical wave front of radius r. Let the incident electric field be E 0 and power of radiation of mobile phone or around the transmission tower is P, the radiating power per unit area is represented by the equation.
Where C the velocity of radiation and is the permittivity of free space And from the mobile phone tower of power 20W, then electric field is given by = . (2) During propagation of electromagnetic wave inside the tissue of biological material, the field strength will further reduce due to dissipation then the electric field decreases exponentially with distance from the boundary and is given by the equation Where E 0 is the magnitude of the field inside the boundary, E z is the field inside the depth z and δ is skin depth. For biological materials skin depth is given by Where εthe permittivity, ω is the angular frequency of radiation, σ is the conductivity of biological material and µ is the permeability of materials of tissues.
By Pointing vector theorem SAR can be defined as Where . is the field inside that material and σ is the conductivity of the material, / is the density of bio material. This relation shows that the rate of electromagnetic energy is converted into heat energy through well interaction mechanisms. [10]. The value of density / for skin=1070 kg m −3 , for blood=1060 kg m −3 , for muscles =1050 kgm −3 , for bone= 1520 kg m −3 For frequency of EMW of 10 MHz-10 GHz its safe limit =0.4 W/kg [11].   For the calculation of penetrated electric field inside the body, the distance of mobile phone tower from the body is taken 1 m to 50 cm for this study skeletal muscle and bone tissues at frequencies 800, 900, 1800 and 2450 MHz and power of radiation of mobile phone tower is 20 W.                       Table 2,3, 4and 5 represent penetrating the electric field (V/m) at 0.1mm to 0.5mm depth inside the muscle tissues due to the electromagnetic wave of frequencies 800, 900, 1800 and 2450 MHz from 1 m to 50 m distance from the mobile phone tower. The calculated penetrated electric field in these tables decreases as the distance from the tower is increased. 98.00% penetrated electric field increases at different depth in the body when moves from 50 m to 1 m towards the tower. Table 6, 7, 8 and 9 represent penetrating the electric field (V/m) at 0.1mm to 0.5 mm depth inside the bone tissues due to the electromagnetic wave of frequency 800, 900, 1800 and 2450 MHz from 1 m to 50 m distance from the mobile phone tower. The calculated electric field given in these table decreases as the distance from the tower is increased. 98.00% penetrated electric field increases at different depth in the body when move from 50 m to 1 m towards the tower. Table 10, 11, 12 and 13 represent the specific absorption rate (SAR) for muscle tissues due to EMW of frequency 800, 900, 1800 and 2450MHz. This shows that the value of SAR decreases as the distance is increased. After comparing the data it is found that at 800, 900, 1800 and 2450 MHz frequency of mobile phone tower SAR is harmful to the life of the muscle tissues up to 1m distance from the body till 0.5 mm depth. Table 14, 15, 16 and 17 represent the SAR for bone tissues due to EMW of frequency 800, 900, 1800 and 2450 MHz. From this it is found that at 800, 900, 1800 and 2450 MHz frequency of mobile phone tower SAR is safe for the life of the bone tissues up to 1m distance from the body till 0.5 mm depth.

Conclusions
As go towards the mobile phone tower from 50 meters to 1m, the penetrated electric field increase 98.00% for both muscle and bone tissues of the human body at frequencies 800, 900, 1800 and 2450 MHz. According to some International agencies as ICNIRP, WHO the specific absorption rate (SAR) becomes harmful after 1.6 W per kg. of the body weight of 75 kg. The average safe limit of SAR is 0.4 W/kg, it means that if SAR becomes greater than 120 W/kg. It may be harmful to the tissues of the human body.
It concludes from the tables 10, 11, 12 and 13, that at 800, 900, 1800 and 2450 MHz frequencies of mobile phone tower SAR is harmful to the life of the muscle tissues up to 1m from the body till 0.5 mm depth and from tables 14, 15, 16 and 17, it is also found that at 800 ,900 ,1800 and 2450 MHz frequencies of mobile phone tower SAR are safe for the life of the bone tissues up to 1m from the body till 0.5 mm depth.