1. Dr N EshwarChandra MD DNB FRCR FICR
•MBBS KakatiyaMedical College, Warangal, AP
•MD & DNBPGIMER, Chandigarh
•FRCRRoyal College of Radiologists, London
•Present Professor and Head of Radiology, employment KamineniAcademy of Medical Sciences, Hyderabad
•MembershipsIRIA, ISPR, ISNR, ISVIR, IMA, ECR, RSNA, RCR, Musculoskeletal Society
•Invited lecturesOver 80
3. What is EMF
A physicalfieldproduced byelectrically charged objects which affects the behavior of charged objects in the vicinity of the field.
4. What are the types of EMF?
•Nonionisingradiation –radio, computer, microwave, cell phone
•Ionisingradiation –X rays, gamma rays
5. What are the types of nonionisingradiation
•Extremely low frequency: <300 Hz
Electricity power supply and electric appliances
•Intermediate frequency: 300 Hz-10 MHz
computer screens, antitheft devices, security systems
•Radiofrequency: 10 MHz-300 GHz
Radio, television, radar and cellular phones & microwave ovens
8. What are the effects of EMF?
•Biological Effect: A biological effect is the physical alteration that occurs within an organism following an exposure that causes a measurable change in biology.
•Production of heat, auditory clicks
•Health hazard: causes detectable impairment of the health of the exposed individual or of his or her offspring
9. What are the exposure limits?
•The specified levels according to ICNIRP guidelines for power density for frequencies 900MHz &1800 MHz are 4.5W/m2and 9W/m 2respectively
Limit when body start feeling the impact
50 times safety margin exists in ICNIRP
DOT, Government of India has reduced limits by further 10 times
10. What are the safe limits for base stations?
•Working at ground level antenna structures – below safe limits
•Stand off distances at the antennas – 6 feet around for omnidirectional antenna. 6 feet in front for directional(panel/sector) antennas. 1 feet in front for directional (integrated) antenna. 1 feet in front for directional (dish, microwave) antenna.
12. What are the health effects ?
•Only established health effect –increase in traffic accidents when used while driving.
•RF field associated heating not a concern in routine use
13. What is electromagnetic hypersensitivity?
•A phenomenon where individuals experience adverse health effects while using or being in the vicinity of electric, magnetic or EMF sources & devices
•Sleep disorders, headaches, nervousness, fatigue, depression and concentration difficulties.
•Symptoms real, but not attributable to EMF
Major review of 31 provocation studies Rubin et al 2005
14. Are there any harmful health effects from living close to base stations ?
•Do not cause cancer
•RF signals from base stations too low to affect health
15. Are mobile phone safe for children?
•No data to suggest a health hazard
•UK & Sweden: Minimiseuse or minimiseexposure
•More research recommended by WHO
16. No documented effects on brain cancer, cognition, leukemia, health disturbances, embryonic or fetal development
17. Do mobiles towers affect birds, animals, trees?
•No evidence of a significant environmental impact
18. Can a radiation shield protect us from EMF exposure ?
•Scientific evidence does not indicate any need for shields.
•Hands free devices can reduce exposure by 10 times