Dr N Eshwar Chandra MD DNB FRCR FICR

• MBBS Kakatiya Medical College, Warangal, AP

• MD & DNB PGIMER, Chandigarh

• FRCR Royal College of Radiologists, London

• Present Professor and Head of Radiology, employment Kamineni Academy of Medical Sciences,

Hyderabad

• Memberships IRIA, ISPR, ISNR, ISVIR, IMA, ECR, RSNA, RCR, Musculoskeletal Society

• Publications 6

• Invited lectures Over 80

Electromagnetic fields & Health

Dr N Eshwar ChandraProfessor & HOD

Kamineni Academy of Medical Sciences, Hyderabad

What is EMF• Electromagnetic field:

A physical field produced by electrically charged objects which affects the behavior of charged objects in the vicinity of the field.

What are the types of EMF?

• Nonionising radiation – radio, computer, microwave, cell phone

• Ionising radiation – X rays, gamma rays

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

What are the causes of natural sources of EMF ?

What are the causes of man made sources of EMF ?

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

What are the exposure limits?• The specified levels according to ICNIRP guidelines for

power density for frequencies 900MHz &1800 MHz are

4.5W/m2 and 9W/m 2 respectively

Threshold Zone Limit when body start feeling the impact

900 mHz 230 W/m2

1800 mHz 460 W/m2

Safe Zone ICNIRP limit

900 mHz 4.5 W/m2

1800 mHz 9.2 W/m2

50 times safety margin exists in ICNIRP

Safe Zone ICNIRP limit

900 mHz 0.45 W/m2

1800 mHz 0.92 W/m2

DOT, Government of India has reduced limits by further 10 times

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 omni directional 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.

What are the monitoring agencies?

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

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

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

Are mobile phone safe for children?

• No data to suggest a health hazard

• UK & Sweden: Minimise use or minimise exposure

• More research recommended by WHO

No documented effects on brain cancer, cognition, leukemia, health disturbances, embryonic or fetal development

Do mobiles towers affect birds,

animals, trees?

• No evidence of a significant environmental impact

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

Can mobile phones cook eggs and make pop corn?

Can mobile phones cook eggs and make pop corn?

Snopes.com

•Lead•Magnetic fields (ELF)•Metronidazole•Post menopausal HRT•Phenytoin•Progestin only pills•Zidovudine (AZT)

Conclusion