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This study examines the relationship between mobile phone frequency exposure and safety criteria, specifically focusing on the dosimetry and potential health effects. The study analyzes the induced field strengths in different tissues and measures SAR (Specific Absorption Rate) to assess the impact on temperature increase. Experimental setups and measurements are conducted to gather data and analyze the effects of mobile phone exposure on various biological parameters. The results show significant changes in weight, sperm count, apoptosis, antioxidant activity, micronuclei formation, histone kinase activity, testosterone level, caspase-3 activity, reactive oxygen species, and melatonin activity in exposed rats compared to the sham-exposed group.
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Bio-Dosimetric Relationalship of Mobile Phone frequency Exposure and the Safety Criteria School of Environmental Sciences Jawaharlal Nehru University, New Delhi. Amity Institute of Environmental Toxicology Safety and Management Amity University, Noida (U.P). Jitendra Behari
Introduction To Electromagnetic Radiation • Electromagnetic radiation is all around us. We are being bombarded with unseen waves of electric and magnetic charges that may be physically harmful to our bodies. • Waves of energy propagated through space as a result of electric charges. These charges are emitted from devices that produce, transmit, or use electric power.
Mobile phones operate at a variety of frequencies between about 800 and 2200 MHz. Mobile Phones base station antennas emit EMR in the range 1800 – 2000 MHz Computer monitors emit a broad range of EMR from 30 Hz up to 300 KHz.
To analyze the possible range of variations of the induced field strengths in the various tissues requires an extensive effort, since the local field strengths strongly depend on a large number of parameters, such as: • Ratio of length of the body to the wavelength (L/λ) • Operational frequency and antenna input power • Position of the device with respect to the head/body • Design of the device • The outer shape of the head • The distribution of the different tissues within the head and • The location of the body with respect to the surroundings • The electric properties of the tissues. The last four factors are different for various individuals and can even change with time.
The induced field data are used for computation of SAR is carried out using the expression: SAR = σ *E2/ρ-------(1) σ = Conductivity (S/m) E = Induced field (V/M) ρ= Density of the material (Kg/m3) SAR can be related to increase in temperature SAR= c* ∆T/∆t-------(2) ∆T= Change in temperature (°C) ∆t= Duration of exposure (S) c= Specific heat capacity ( J/Kg°C)
SAR is also dependent upon if the wave type, that is, square, sine or triangular. The power of the square is larger than the other two. The local SAR refers to the value within a defined unit volume or unit mass, which can be arbitrarily chosen.
Measurement of field distribution: Experimental set up Anechoic chamber Rat restrainer Rat cage
Calibration methodology of power emitted from mobile phone during exposure in animal exposure box
Figure 1. (A) sketch diagram of anechoic chamber with animal cage indicating individual animal’s position. (B) Exposure chamber indicating microwave oven connected with probe and releasing power through horn antenna (1369.8 cm). (C) An internal image of exposure chamber at the side of horn antenna. The internal area of chamber is lined with absorbing material.
Exposure set up of 3G mobile phone in Perspex box made of Plexiglass
1- Monopole Probe 1718 MHz 2- Mobile Phone (Nokia 2730 Classic) 3- Angular Probe Positioner 4- Spectrum Analyzer Agilent N9912A 5- R.F Cable (Low loss) 6- Small Size Rodent Box a = 120 mm b= 45 mm c= 25 mm d= 20 mm e= 25 mm f= 50 mm MOTOR Angular Probe Posi Mob Angle (0° to 20 ° ) c 5 1 2 3 4 6 Ref(0) d b Brain Phantom 0→ Reference point 0→ 1 = 25mm 0→2 = 50 mm 0→3 = 75 mm 0→4 = 100 mm 0→5 = 125 mm 0→6 = 150 mm e a Monopole Probe SPECTRUM ANALYZER Model- N9912A
SAR in brain phantom contained in a Perspex box at various mobile phone locations
SAR Measurement (induced field )in Brain Phantom Contained in a box SAR Measurement in 10 gm Brain Phantom
Exposure Procedure • Frequency – 10 GHz/2-35 GHz • Exposure time – 2 hours/day • Duration – 45 days • Animal age – 70 days old • Animal sex – male rats • Animal weight - 190 ± 10 grams • Group – exposed and sham exposed • Power density - 0.21mW/cm2 • SAR - 0.014W/kg
Comparative analysis of animal weight Significant decrease (P < 0.006)
Flow Cytometry analysis of mobile phone exposed and sham exposed Sperm Cells Control Exposed * * Sperm count Apoptosis Significant decrease in exposed group, (p<0.02)
RF/Cell Phone Effect: GPx, SOD, CAT Activity in Brain GPx, SOD in exposed rats, while CAT
Comparative study of Micronuclei and Histone Kinase Comparative statistical analysis of mobile phone exposure effect on micronuclei formation in peripheral blood and histone kinase activity in rat sperm showing significant changes in the exposed group as compared to the sham-exposed group (P<0.05)
* * Sham Exposed Exposed Sham Exposed Exposed Testosterone Caspase-3 activity Activity Apoptosis
Antioxidant activity: Glutathione Peroxidase and Catalase Significant change in GPx and CAT (P < 0.05)
Antioxidant activity: Superoxide dismutase Significant decrease (P < 0.05)
Reactive Oxygen Species Significant increase (P < 0.05
Melatonin activity in pineal gland Significant decrease in exposed group (P < 0.05)
Creatine kinase activity Significant increase in exposed group (P < 0.05)
Caspase-3 activity: Apoptosis Significant increase in exposed group (P < 0.05)
Sperm Protein Kinase C * Significant decline (P < 0.05)
Sperm counts from male Wistar rats exposed to mobile phone radiation Significant set at P<0.005 Significant set at P<0.05
The effects of mobile phone on the MDA production in sperm Significantly different form the control (P < 0.05). Significance set at p < 0.05.
It can be concluded that there are various indicators of tumour promotion, due to electromagnetic field exposure ,but not limited to the following and can be summarised thus: • 1.Increase in ODC and PKC activity. • 2.Increase in Ca2+ efflux. • 3.Altered anti oxidant enzyme activity(GX,GSH,Catalase) • 4.DNA strand break (single and double) • 5.Na+/k+ Phosphatase activity • 6.Decreased melatonin levels • 7.Histone kinase activity • Cancer promotion (Stress Development/RF/MW Syndorme)/Effecting reproduction parameters
EMF 50GHz Free Radical Formation Reactive oxygen species (O2-, H2O2, OH-) Gene activation/inactivation (free-radicals play active role in gene activation) Stress Antioxidant Enzyme Histone Kinase Cell Cycle Estimation Apoptosis GPx G2-M phase G0-G1 Phase SOD S Phase Spermatogenesis CAT Infertility
Cell membrane Signal transduction & amplification Plasma membrane Nucleus, DNA Biochemical messenger Enzymes, Genes, Proteins Co-operativism + Non linearity + Non-equilibrium thermodynamic behavior Amplifying effect of ELF-EMF Transmembrane coupling of signal to cytoplasm (By soliton waves?) Effect of ELF-EMF: Signal transduction
B After time F I I I F I DNA chain bending • A direct result of equation (7) is the relationship between flowing charge (current), magnetic field, and induced force shown in equation (8) below • Direction of current flow is opposite in 2 wires, applied MF causes repulsion • If DNA helix is considered 2 “wires” carrying charge through electron transport in opposing directions MF exposure may bend chain in some instances
Radio Frequency Radiation Brain cells Bone Neurons Osteoblast Positive effect Fracture healing Single strand DNA break Double strand DNA break Ostoep orosis Control Control Health hazard ? Tumor promoter ?
Typical diagram of antenna system for measurement of emissions from mobile towers
SUMMARY OF EMF MECHANISMS • Chronic exposure to EMF creates free radicals which damage DNA, etc. • EMF depress melatonin synthesis and deprive the body fluids of needed anti- oxidative status. • EMF interfere with evolutionarily developed vital life processes (heart beat, brain signals, wound healing etc)