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VOL. 2, NO. 11, October 2011

ISSN 2079-8407

Journal of Emerging Trends in Computing and Information Sciences

http://www.cisjournal.org

Effect of GSM Phone Radiation on Human

Pulse Rate (Heartbeat Rate)

A. A. Ayeni

, K.T. Braimoh

, O. B. Ayeni

Department of Telecommunication Science, University of Ilorin

wuleemu@yahoo.co.uk,

ayeni@unilorin.edu.ng

Department of Radiology, College of Health Sciences, University of Ilorin

wolebraimoh@yahoo.com

Department of Electrical Engineering, University of Ilorin

O_bayles@yahoo.com

ABSTRACT

Concern about human exposure to radiofrequency (RF) is not new. The conveniences and satisfaction derived in the use of

GSM mobile phone is being threatened by claims of adverse effects on human health by radiation coming from this device.

This radiation belongs to the type called non-ionizing radiation the health hazard of which remains debatable. Research has

not been carried out on possible effect this device might have on human health and no experimental proof, based on data

obtained within Nigeria, exist to substantiate any claim. Safety standards exist for radiation from cell phone but these are not

reassuring. This paper investigates any possible effect of GSM mobile phone radiation on human heart rate and then come

out with conclusion based on experimental proof. Over one hundred human subjects were monitored by measuring their

pulse rate under three exposure criteria. In one of the radiation tests, the phone used was put in vibration mode in order to

determine subjects were not just responding to vibration. It was found out pulse rate do not change significantly when

subjects were exposed to phone radiation. However, the percentage decrease recorded by people of age 40 years and above,

even though barely above 1% makes it advisable that people of age 40 years and above should avoid keeping mobile phones

close to the heart.

Keywords

Phone Radiation, Human Pulse Rate, Radio Frequency

1. INTRODUCTION

Concern about human exposure to radio

frequencies (RF) is not new [1]. The development and

application of devices that emit radio frequency radiation

have significantly increased the quality of life throughout

the world. Due to wide spread use of the Global System for

Mobile Communications (GSM) mobile phones they have

become indispensable as communication tools. But also, the

proliferation has been accompanied by the Public’s fear of

potential adverse effects.

Apart from the naturally occurring cosmic

microwave background radiation (CMBR) in which the

human organism developed, we are being daily bombarded

by the ever increasing unseen radiation being spewed out by

mobile phones and their towers that straddle our residential

environment. Cell phones transmit and receive

electromagnetic (EM) waves, mainly at frequencies of 800-

1900 MHz [2]. There is an enormous increase in the use of

wireless mobile telephony throughout the world as there

were more than 4.3 billion users worldwide as of July 2009

[3]. Adverse effects of these important communications

tools are being reported. Sensations of burning or warmth

around the ear, headache[4], disturbance of sleep, alteration

of cognitive function and neural activity, are some of the

effects being reported as resulting from mobile phone use.

In spite of previous studies, knowledge about the adverse

effect of radiofrequency and microwaves (RF/MW)

radiation on human health, or the biological responses to

RF/MW radiation exposure is still limited. Mobile phones

are usually held in the close proximity to the human heart

therefore exposure to radiation is high. Also worrisome is

the fact that some people in Nigeria live virtually under

GSM base stations.

And if truly any level of mobile phone radiation

cause significant alteration in the condition of human heart,

then we may be all pretty much on death row!

2. ABSORPTION OF RF RADIATION BY

HUMAN BODY

Biological tissue is, for all practical purposes, non-

magnetic with a permeability µ (H/m) close to that of free

space [5]. There are three established basic coupling

mechanisms through which time-varying electric and

magnetic fields interact directly with living matter

(UNEP/WHO/IRPA 1993): The one relevant to this study is

‘absorption of energy from electromagnetic fields’. As

regards absorption of energy by the human body,

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VOL. 2, NO. 11, October 2011

ISSN 2079-8407

Journal of Emerging Trends in Computing and Information Sciences

http://www.cisjournal.org

electromagnetic fields can be divided into four ranges

(Durney et al. 1985). GSM phones fall within one of these

ranges which are ‘frequencies in the range from about 300

MHz to several GHz, at which significant local, non-

uniform absorption occurs [6]. The absorption effects of RF

energy by the biological body vary in magnitude with both

the frequency of the applied field and the characteristics of

the tissue material, which is largely based on water and ionic

content [5]. The table 1 shows the penetration depth of

waves of increasing frequency in typical body tissues and

illustrates how high-water-content tissues such as blood and

muscle and more absorptive than low-water-content tissues

such as fat [5] (i.e. the more the penetration depth, the less

the absorption and vise-versa).

Table 1:

Penetration depth in selected biological tissues as a

function of frequency

Depth of penetration (mm)

Frequency

MHz

Blood

Muscle

Brain

Fat

150

46.0

67.1

93.7

342

915

27.8

42.1

47.2

250

2450

16.2

22.3

23.1

122

5800

6.0

7.5

7.9

40.9

(Source: Electronics & Communication journal volume13,

No2. IEE 2001)

Based on the absorption level of blood and muscle

as shown in the table, the human heart made up of blood and

muscle could be vulnerable. The more reason proximity to

the heart of radiation emitting gargets should be a concern.

One way of determining the RF exposure level due

to phones is by measuring the device’s specific absorption

rate (SAR). The SAR constitutes the measures of power

absorbs per unit mass, in other words, the amount of power

the body absorbs. Determining SAR requires laboratory

analysis and involves measuring factors such as average

phone usage and the unit’s distance from the body [7].

Manufacturers are required to use the specific

anthropomorphic mannequin (SAM) phantom [1]. SAR is

measured in watt per kilogram (W/kg) averaged over one

gram of body tissue as in north America standard or over ten

grams of body tissue as in European standard. SAR limits

are based on whole-body exposure levels of 0.08 W/kg.

Limits are less stringent for exposure to hands, wrists, feet,

and ankles. Most SAR testing concerns exposure to the

head. For Europe, the current limit is 2 W/kg for 10-g

volume-averaged SAR. For the United States and a number

of other countries, the limit is 1.6 W/kg for 1-g volume-

averaged SAR [1].

rating, one of the best phones in energy emitted is Samsung

Impression SGH-a877 with rating of 0.35, while one of the

worst has the rating of 1.55W/kg [8]. The lower the SAR

rating of a phone the better it is. Therefore using a phone

with SAR rating of 1.15 represents a near worst-case

scenario.

Fig. 1:

Nokia 1200

Nokia1600, also of the same dual band, SAR rating

1.12 (1.6W/kg) / 0.82 (2.0W/kg), was used as transmitting

phone (Fig. 2).

The SAR ratings of both the receiving and

transmitting mobile phones fall within the international

standard of exposure limit for public exposure which is

1.6W/kg radiation rating averaged over one gram of body

tissue [1]. Hence there is no question of putting the subject

under any hazard risk. Their safety is therefore guaranteed

based on international standard.

3. RADIATION SOURCE AND PULSE RATE

MONITORING

A dual band (900MHz, 1800MHz) Nokia1200

(Fig. 1), in receiving mode was used as radiation source. Its

SAR rating is 1.15 based on 1.6W/kg averaged over one

gram of body tissue or 0.81 based on 2.0W/kg averaged

over ten grams of body tissue. Based on 1.6W/kg radiation

Fig. 2:

Nokia 1600

A 14.1 x 11.3 x 6.0cm battery powered automatic

inflate/deflate arm pulse rate monitor with arm strap/cuff for

arm circumference 24-36cm (Fig. 3) was used to monitor

the pulse rate of the subjects. The digital display of the

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VOL. 2, NO. 11, October 2011

ISSN 2079-8407

Journal of Emerging Trends in Computing and Information Sciences

http://www.cisjournal.org

monitor makes reading less cumbersome. When the start

button is pressed once, the unit will automatically start to

inflate slowly to measure the pulse rate. During inflation, a

changing measure of the cuff pressure is shown on the

display. At a point, the pressure then begins to drop. When

the cuff pressure has dropped to the point where the monitor

can no longer detect the pulse, the subject’s pulse rate will

be displayed.

Fig. 3(a):

Pulse rate monitor with the arm cuff

Recording tool (data sheet and writing material)

made it easier to organize the data.

All the above instruments were used without

prejudice to subject personal health welfare.

The following activities were carried out in the

pulse rate monitoring process:

The study group used as experimental subjects

consisted of 102 human volunteers with age bracket

ranging from 10-20years to 71-80years. The participants

satisfied the following inclusion criteria: age-brackets of

subjects are all within the age group of GSM phone users;

arm circumference of subjects is reasonably within

monitor’s cuff fitting.

A battery powered automatic inflate/deflate

digital display arm pulse rate monitor with arm strap/cuff

which measures pulse rate was used to monitor the pulse

rate of individual in the group. Each subject went through

three checks under the same environmental and physical

condition but different radiation exposure criteria. The

normal output of a consumer mobile phone operating at

GSM frequency of 900/1800MHz mobile phone was used

as GSM radiation source (Fig. 1).

The three radiation exposure criteria are:

i. Pulse rate monitoring without the subject been

expose to any radiation and subject fully aware of

this.

ii. Pulse rate monitoring with the subject expose to

radiation from a call receiving mobile phone on

vibration.

iii. Pulse rate monitoring with the subject expose to

radiation from a call receiving mobile phone with

vibration off.

To achieve the criteria the three tests were carried out

as follows:

The cuff of the monitor was wrapped around the arm

above the elbow of the human subject and the pulse rate

(b)

Monitor’s display

was measured while he/she was not exposed to any

radiation from GSM phone.

With the same position maintained the test was

carried out again but this time with a mobile phone in the

subject’s breast pocket or held against the chest in the

absence of breast pocket. Holding the phone in such close

proximity to the heart represent the worst-case scenario.

Call is made to this phone with vibration set on and while

this was going on, the pulse rate was measured.

The same procedure as the second test was repeated

but with vibration set off. The duration of radiation

exposure was generally in the average of 20 seconds, a

typical duration for a receiving phone kept in the breast

pocket to ring before a call is picked or terminated.

The three tests were carried out under the same

physical and environmental conditions such as location,

body position, ambient temperature and external

distractions, to eliminate or minimize confounding effects

on readings due to these external factors. Physical activity

such as changing seats can alter pulse rate [9]. So such

influencing factors were kept constant.

Fig. 4 shows the demonstration of test carried out on

the subjects.

4. GRAPHS AND GRAPHICAL ANALYSIS

In order to bring about a more robust analysis,

the collected data, as well as the analysis, is sectionalized

into the following groups which represent sub-tables:

grown-up children (age-bracket 10-20yrs), youth (age-

bracket 21-30yrs), young adult (age-bracket 31-40yrs),

adult (age-bracket 41-80yrs). Children below age 10

years can be considered non-phone users.

Based on the data collected through the

monitoring, the following graphs were plotted.

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VOL. 2, NO. 11, October 2011

ISSN 2079-8407

Journal of Emerging Trends in Computing and Information Sciences

http://www.cisjournal.org

Fig. 4:

Demonstration of Test

Graph of Pulse rate of Experimental Subject Age-bracket 10-

20years under three different Radiation Exposure Criteria

120

Pulse Rate (Beat/minute)

100

A B C D E F G H I J K L M N O P Q R S T

Experimental Subjects

No Exposure

Exposure vib ON

Exposure vib OFF

Fig. 5:

Graph of pulse rate against experimental subjects of children (age-bracket 10-20yrs)

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VOL. 2, NO. 11, October 2011

ISSN 2079-8407

Journal of Emerging Trends in Computing and Information Sciences

http://www.cisjournal.org

Graph of Pulse Rate of Subjects of Age-bracket 21-30years

under the three Radiation Exposure Criteria

140

120

Pulse Rate (beat/minute)

100

Experimental Subject

Pre-Exposure

Exposure Vibration ON

Exposure Vibration OFF

Fig. 6:

Graph of pulse rate against experimental subjects of youth (age-bracket 21-30yrs)

Graph of Subjects' Pulse Rate in the Age-bracket 31-40years

under the three Radiation Exposure Criteria

120

Pulse Rate (beat/minute)

100

Experimental Subject

Pre-Exposure

Exposure Vibration ON

Exposure Vibration OFF

Fig. 7:

Graph of pulse rate against experimental subjects of young adult (age-bracket 31-40yrs)

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