THE THERMAL EFFECTS OF 900 MHz CELL PHONES ON THE BRAIN PHANTOM

Öz

Investigation of the effect of mobile phones in the terms of human health is getting more important position in the literature due to the increased public concern. An experimentally efficient setup was established to determine the thermal effects caused by mobile phones in the brain. Temperature increasing in the brain during exposing the mobile phone is investigated in a brain equivalent liquid (phantom). In the proposed experimental setup, mobile phone which operates at 900 MHz frequency was represented with a radio frequency (RF) generator which has a half-dipole antenna and this system is applied to phantom at different distances. Thermal absorptions were observed by sensitive temperature sensors at different depths. Effects of electromagnetic fields are usually investigated via numerical methods and simulations in the literature. In this study, an experimental analysis of temperature distributions in the human brain phantom exposed to mobile phone radiation at 900 MHz is presented. All experiments were conducted in an anechoic chamber where temperature variation is about 0.009oC. Additionally, high-power electromagnetic fields are used such as 4W, 7W and 10W which are not implemented till now in the literature for GSM frequencies. Different temperature distribution in the phantoms was observed by systematically changed distances and power options. In this last case, maximum temperature elevation was observed as 0.403oC. While the temperature elevation increases with increasing applied power, removing the mobile phone from the phantom reduce the temperature elevation in the phantom.

Anahtar Kelimeler

• Electromagnetic Thermal Effect
• Brain Phantom
• 900 MHz Electromagnetic Field

Kaynakça

1. 1. Aly A.A., Cheema M.I., Tambawala M., Laterza R., Zhou E., Rathnabharathi K. & Barnes F.S. (2008). Effects of 900-MHz Radio Frequencies on the Chemotaxis of Human Neutrophilsin Vitro. IEEE Transactions on Biomedical Engineering, 55(2), 1222-1248.
2. 2. Bei W. & Cao Y. (2007). “Biological Effects of Electromagnetic Radiation”. Radiation Protection Bulletin, 27(3), 27-45.
3. 3. Bernardi P., Cavagnaro M., Pisa S. & Piuzzi E. (2000). Specific Absorption Rate and Temperature Increases in the Head of a Cellular-Phone User. IEEE Transactions on Microwave Theory and Techniques. 48(7), 1118-1126.
4. 4. Bernardi P., Cavagnaro M., Pisa, S. & Piuzzi, E. (2003). Specific absorption rate and temperature elevation in a subject exposed in the far-field of radio-frequency sources operating in the 10-900-MHz range. IEEE Transactions on Biomedical Engineering, 50(3), 295-304.
5. 5. Chia S. E., Chia H.P. & Tan J.S. (2000). Prevalence of headache among handheld cellular telephone users in Singapore: A community study. Environmental Health Perspect 108(11), 1059-1062.
6. 6. Citkaya A.Y. & Seker S.S. (2012). FEM modeling of SAR distribution and temperature increase in human brain from RF exposure. International Journal of Communication Systems, 25, 1450–1464.
7. 7. Cleveland R.F.S., David M.U. & Jerry L. (1997). Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields; OST Bulletin No. 65 ed. 97-01.
8. 8. Diem E., Schwarz C., Adlkofer F., Jahn O. & Rüdiger H. (2005). Non-thermal DNA breakage by mobile-phone radiation (1800 MHz) in human fibroblasts and in transformed GFSH-R17 rat granulosa cells in vitro. Mutation Research 583,178-183.

9. 9. Durney C.H., Massoudi H. & Iskender M.F. (1986). Radiofrequency dosimetry handbook, 4th Ed., Brooks Air Fors Base, Taxas.
10. 10. Fields, R.E. (1997). Evaluating compliance with FCC guidelines for human exposure to radiofrequency electromagnetic fields. OET Bulletin, 65(10).
11. 11. Gabriel C. (1996). Compilation of the dielectric properties of body tissues at RF and microwave frequencies Brooks air force technical report AL/OE-TR-1996-0037. Armstrong Laboratory, Brooks Air Force Base, TX.
12. 12. Gandhi O.P., Lazzi G., Tinniswood A. & Yu Q.S. (1999). Comparison of numerical and experimental methods for determination of SAR and radiation patterns of handheld wireless telephones. Bioelectromagetics, 20(1), 93-101.
13. 13. Gimm Y.M. (2004). General Method of Formulating the Human Tissue Simulant Liquid for SAR Measurement. Emc International Symposium on Electromagnetic Compatibility. Netherland 2004, 2, 561-564.
14. 14. Hakim B.M. (2006). Precise SAR Measurements in the Near-Field of RF Antenna Systems, Doctorate Thesis, 131 p.
15. 15. Hartsgrove G., Kraszewski A. & Surowiec A. (1997). Simulated biological materials for electromagnetic radiation absorption studies. Bioelectromagnetics, 8(1), 26-36.
16. 16. Hermann D.M. & Hossmann K.A. (1997). Neurological effects of microwave exposure related to mobile communication. J. Neurol. Sci. 152(1), 1-14.
17. 17. IEC 62209-1 (2005). “Human exposure to radio frequency fields from hand-held and body-moumted wireless communication devices–human models, instrumentation, and procedures–Part 1: Procedure to determine the specific absorption rate (SAR) for hand-held devices used in close proximity to the ear (frequency range of 300 MHz to 3 GHz)”, IEC, 2005.
18. 18. IEEE 1528 (2003). Recommended Practice for Determining the Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Body Due to Wireless Communications Devices: Experimental Techniques, IEEE Standard 1528, 2003.
19. 19. Jianqing W. & Fujiwara O. (1999). FDTD computation of temperature rise in the human head for portable telephones. IEEE Transactions on Microwave Theory and Techniques, 47(8), 1528-1534.
20. 20. Jianqing W. & Fujiwara O. (2003). Comparison and evaluation of electromagnetic absorption characteristics in realistic human head models of adult and children for 900-MHz mobile telephones. IEEE Transactions on Microwave Theory and Techniques, 51(3), 966-971.
21. 21. Kanda M. Y., Ballen M., Salins S., Chou C.-K. & Balzano Q. (2004). Formulation and Characterization of Tissue Equivalent Liquids Used for RF Densitometry and Dosimetry Measurements. IEEE Transactions on Microwave Theory and Techniques, 52(8), 124-129.
22. 22. Kaori F., Soichi W. & Yukio Y. (2004). Dielectric Properties of Tissue-Equivalent Liquids and their Effects on Specific Absorption Rate. IEEE Transactions on Electromagnetic Compatibility, 46(1), 112-123.
23. 23. Kassimi S., Elfadl A., Bri S., Nakheli A., Habib M. & Ben Ahmed M. (2012). Thermal Effects of Mobile Phones. International Journal of Emerging Technology and Advanced Engineering, 2(9), 110-124.
24. 24. King H. & Wong J. (1977). Effects of a human body on a dipole antenna at 450 and 900 MHz. IEEE Transactions on Antennas and Propagation, 25(3), 376-379.
25. 25. Koichi I., Katsumi F., Yoshinobu O. & Lira H. (2001). Development and Characteristics of a Biological Tissue-Equivalent Phantom for Microwaves, Electronics and Communications in Japan, Part 1, 84(4), 1-72.
26. 26. Kuster N. & Balzano Q. (1992). Energy absorption mechanism by biological bodies in the near field of dipole antennas above 300 MHz. IEEE Transactions on Vehicular Technology, 41(2), 17-23.
27. 27. Kuster N., Kästle R. & Schmid T. (1997). Dosimetric evaluation of handheld mobile communications equipment with known precision. EICE Transactions on Communications , 80-B(5), 645–52.
28. 28. Li C.H., Douglas M., Ofli E., Chavannes N., Balzano Q. & Kuster N. (2012a). Mechanisms of RF Electromagnetic Field Absorption in Human Hands and Fingers. IEEE Transactions on Microwave Theory and Techniques 60(7), 2267-2276.
29. 29. Li C.H., Douglas M., Ofli E., Chavannes N., Balzano Q. & Kuster N. (2012b). Influence of the Hand on the Specific Absorption Rate in the Head. IEEE Transactions on Antennas and Propagation, 60(2), 1066-1074.
30. 30. Liu J., Ren Z. & Wang C. (1995). Interpretations of living tissue’s temperature oscillations by thermal wave theory. Chin Sci Bull 40(1), 1493-1495.
31. 31. Mann K. & Roschke J. (1996). Effects of pulsed high-frequency electromagnetic fields on human sleep. Neuropsychobiology. 33(1), 41-47.
32. 32. Mushtaq A.B. & Vijay K. (2013). Calculation of SAR and Measurement of Temperature Change of Human Head due to the Mobile Phone Waves at Frequencies 900 MHz and 1800 MHz. Advances in Physics Theories and Applications, 16, 54-63.
33. 33. Nakamura H., Matsuzaki I., Hatta K., Nobukuni Y., Kambayashi Y. & Ogino K. (2003). Non thermal effects of mobile-phone frequency microwaves on utero-placental functions in pregnant rats. Reprod Toxicol. 17(3), 321-326.
34. 34. Okano Y., Hase A. & Ito K. (2000). A brain-equivalent solid phantom and its application to SAR estimation by the thermographic method. Electronics and Communications in Japan Part II-Electronics, 83(12), 24-34.
35. 35. Onishi T., Kiminami K. & Iyama T. (2008). I Novel Specific Absorption Rate Measurement Techniques. 2008 Asia-Pacific Symposium on Electromagnetic Compatibility & 19th International Zurich Symposium on Electromagnetic Compatibility, 19–22 May 2008, Singapore p.120-123.
36. 36. Özen Ş. & Köylü H. (2003). Phantom Model of Human Brain Tissue for Cellular Phone Frequencies in Electromagnetic Field Radiation Absorption Studies. G.U. Journal of Science 18(2), 193-200.
37. 37. Özen S., Helhel S. & Bilgin S. (2011). Temperature and Burn Injury Prediction of Human Skin Exposed to Microwaves: a Model Analysis. Radiation and Environmental Biophysics, 50, 483-489.
38. 38. Özen S., Helhel S. & Çolak Ö.H. (2006). Temperature Increase and SAR in a Phantom Model of the Human Head Exposed to 1800 MHz Non-Ionizing Radiation. 4th International Workshop on Biological Effects of Electromagnetic Fields Proceedings, pp.1106-1109, Crete, GREECE, 16-20 October 2006.
39. 39. Özen Ş., Onural A.Ş. Çömlekçi S. & Çerezci O. (2004) Experimental Determination of Heat Rise and SAR Occurred by 900 MHz EM Radiation on Human Brain by Using Brain Phantom Model. Gazi University Journal of Science, 17(3), 127-132.
40. 40. Pšenáková Z. & Benová M. (2008). Measurement Evaluation of Emf Effect by Mobile Phone on Human Head Phantom. Advances in Electrical and Electronic Engineering, 7(1), 2350-353.
41. 41. Riu P.J. & Foster K.R. (1999). Heating of Tissue by Near-Field Exposure to a Dipole: A Model Analysis. IEEE Transactions on Biomedical Engineering. 46(8), 911-917.
42. 42. Rusnani A. & Norsuzila N. (2008). Measurement and Analysis of Temperature Rise caused by Handheld Mobile Telephones using Infrared Thermal Imaging. IEEE International Rf and Microwave Conference, December 2-4, 2008, Kuala Lumpur, Malaysia.
43. 43. Schmid T., Egger O. & Kuster N. (1996). Automated E-field scanning systems for dosimetric assessments. IEEE Transactions on Microwave Theory and Techniques 44(1), 105–113.
44. 44. Schwan H.P. & Piersol G.M. (1954). The absorption of electromagnetic energy in body tissues. American Journal of Physical Medicine, 33(1), 371-404.
45. 45. Shamsad F. & Amin M. (2012). Simulation Comparison between HFSS, CST and WIPL-D for Design of Dipole, Horn and Parabolic Reflector Antenna, Journal of Expert Systems (JES), 1(4), 203-207.
46. 46. Stuchly M.A. & Stuchly S. S. (1990). Electrical properties of biological substances”. In Gandhi Op. (ed): Biological effects and medical applications of electromagnetic energy. Englewood Cliffs, NJ: Prentice Hall, pp. 75-112.
47. 47. Suzana H. & Suzana H. (2009). The Human Brain in Numbers: a Linearly Scaled-up Primate Brain. Frontiers in Human Neuroscience, 3, 1-11.
48. 48. Taurisano M.D. & Vorst A.V. (2000). Experimental Thermographic Analysis of Thermal Effects Induced on a Human Head Exposed to 900-MHz Fields of Mobile Phones. IEEE Transactions on Microwave Theory and Techniques, 48(11), 1148-1152.
49. 49. URL-1 (2014). https://mobiforge.com/research-analysis/global-mobile-statistics-2014-part-a-mobile-subscribers-handset-market-share-mobile-operators (The International Telecommunication Union. Global mobile statistics Part A: Mobile subscribers; handset market share; mobile operators MAY 2014).
50. 50. Virtanen H., Keshvari J. & Lappalainen R. (2007). The effect of authentic metallic implants on the SAR distribution of the head exposed to 900, 1800 and 2450 MHz dipole near field. Physics in Medicine and Biology, 52(5), 1221-1236.
51. 51. Zhang M. & Alden A. (2011). Calculation of Whole-Body Sar from A 100 Mhz Dipole Antenna. Progress in Electromagnetics Research, 119(2), 133–153.