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ORIGINAL ARTICLE
Malaysian Journal of Medical Sciences, Vol. 9, No. 2, July 2002 (17-22)
EAR INFECTION AND HEARING LOSS AMONGST HEADPHONE
USERS
R. Mazlan, L. Saim, A. Thomas, R. Said and B. Liyab.
Department of Otorhinolaryngology,
Universiti Kebangsaan Malaysia Hospital.
The use of headphone has been thought to cause infection in the ear canal and
contribute to hearing loss. In this study, we examined 136 Customer Service
Representative from Celcom (Malaysia) Sdn. Bhd. who use headphone throughout
their working hours. The purpose of this study was to determine the prevalence of
ear canal infection and other related diseases of the ear, nose and throat. Their
hearing thresholds were also determined using the Amplaid 309 Clinical
Audiometer. We found no incidence of infection of the external ear canal amongst
the subjects. There were 4 cases of chronic middle ear infection and 4 cases of
impacted wax. Hearing impairment was found in 25 subjects (21.2%). However,
there was no significant association between hearing loss and the exposure to sound
from headphone usage because the high frequencies were not predominantly
affected. There was also no association between hearing loss and duration of service.
Key words : hearing loss, headphone users
Introduction
The use of headphone has been thought to
create aural hygiene problems and infection in the
ear canal. Not uncommonly the headphone user also
express concern regarding the potential for this
device to cause noise induced hearing loss. However,
documented studies on the side effects of prolonged
use of the headphone are rarely described in the
literature. Among the prolonged user of the
headphone are telephonists, radio deejays and
mobile compact personal stereo.
Celcom (Malaysia) Sdn. Bhd. is a major
telecommunication company in Malaysia. A total
number of 141 customer service representatives are
working in the company. Customer service
representatives function as telephonists, which uses
headphone to receive phone calls from Celcom
customer. They work in shift of 8 hours with one-
hour break. Therefore, all of them wear headphones
and receiving calls continuously for 7 hours. Isolated
incidence of ear problems has been reported among
these customer service representatives. It is in the
interest of both the employer and the employee that
a proper study is carried out to determine ear
problems including hearing loss among these
customer service representatives.
Objective
The objectives of this study was to determine
the prevalence of infection of the external ear canal
as well as other ear, nose and throat diseases among
customer service representatives and the hearing
threshold level of these subject using Pure Tone
Audiometry. The presence of hearing loss in relation
to the duration of service was also analysed.
Methodology
Population of Study
118 randomly selected customer service
representatives from Celcom working in Kuala
Submitted-22.5.2001, Revised-21.8.2001, Accepted-16.11.2001
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R. Mazlan, L. Saim, et. al
Sex No. of subjects (n) %
Male 40 33.9
Female 78 66.1
Total 118 100.0
Table 1: Sex Distribution among the subjects
Duration of service No. of subjects (n)
1 4
2 55
3 31
4 11
5 9
6 4
7 1
8 3
Total 118
Table II: Duration of service among the subjects
Table III: Disease of the Ear, Nose and Throat
Ear findings No. of subjects (n)
Impacted wax 4
Active CSOM 2
Chronic Inactive OM 2
Nose findings No. of subjects (n)
Chronic rhinosinusitis 1
Allergic rhinitis 1
Throat findings No.of subjects (n)
Chronic tonsillitis 1
Total 11
Lumpur offices were included in this study from
August 1999 to September 1999. The age of the
subjects ranged from 18 years to 35 years.
Hearing Test
Clinical Audiometer machine, Amplaid 309
was used to determine the hearing threshold level
of the subjects. Hearing thresholds were investigated
in the 250 Hz to 80000 Hz range, which are the
frequencies important for speech perception. Results
were plotted on the audiogram, which showed the
hearing threshold, in decibels hearing level (dB HL)
against frequency in hertz (Hz). Audiometric testing
was performed using TDH-39 headphones and a
bone conductor. Background noise level of the sound
proof room was 30dBA.
Ear examination
All subjects were examined only by the Ear,
Nose and Throat Surgeon. Specific diseases of the
ear canal were looked for and documented.
Examination of nose and throat were also performed.
Definition
Hearing threshold was defined as the lowest
intensity level at which multiple representations are
detected 50% of the time (1).
Normal h ea rin g was defined as having
hearing threshold between –10 dB HL to 20 dB HL
for all frequencies tested (250 Hz to 8000 Hz).
Hearing impairment was defined as having
hearing threshold of more than 20 dB HL in at least
one frequency.
Data analysis
The hearing threshold levels for left and right
ears were analyzed separately where the hearing
impairment among the subjects were determined and
the frequencies of sound divided into three
categories: low frequencies-250 Hz and 500 Hz, mid
frequencies-1 kHz and 2 kHz, high frequencies-4
kHz and 8 kHz
Results
Demographic Data
A total of 136 customer ser vice
representatives were analyzed from Celcom Call
Centre. They worked on shift duty with an average
duration of 8 hours per shift with one hour break.
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EAR INFECTION AND HEARING LOSS AMONGST HEADPHONE USERS
Hearing Status No. of subjects (n) %
Normal hearing 93 78.8
Impaired hearing 25 21.2
Table IV : Number of subjects with normal and
impaired hearing
Frequency Right Ear (n) % Left Ear(n)%
Low (.25 & .5 Hz) 24 20.3 26 22.0
Mid (1k & 2k Hz) 17 14.4 20 16.9
High (4k & 8k Hz) 19 16.1 16 13.6
Total 60 50.8 62 52.5
Table V : Number of ear (left and right) with hearing impairment according tofrequency
Diseases of the Ear, Nose and Throat
A total of 11 subjects were found to have
diseases of ear, nose and throat, as shown in Table
3.
Four subjects were found have impacted wax.
Another 4 subjects were found to have chronic otitis
media. In 2 of them, there were active diseases and
the other 2 were inactive. All of these subjects had
perforated eardrum.
There was one case each of chronic
rhinosinusitis, allergic rhinitis and chronic tonsilitis.
Hearing Impairment
The total number of subjects with normal and
impaired hearing is shown in Table 4.
There were 93 (78.8%) subjects with normal
hearing in both ears. Only 25 subjects (21.2%) were
found to have hearing impairment in either one or
both ears.
The 25 subjects with hearing impairment were
further analyzed. The number of subjects according
to ears with hearing impairment in low, mid and high
frequencies are shown in Table 5.
The numbers of subjects with hearing
impairment in the low, mid and high frequencies
were almost equal in the left and right ear.
Duration of Service among the Hearing Impaired
Figure 2 shows the duration of service among
the hearing impaired subjects. The majority of
The headphone was used on one ear only that is the
prefer r e d ear b y t he s u b j ects , o v er 7 h o u rs
continuously.
Sex Distribution
Table 1 shows the sex distribution of the
subjects. The majority of subjects were females
(66.1%).
Race Distribution
Figure 1 shows the race distribution among
the subjects. Majority (91.1%) of them were Malays.
Duration of Service
The duration of service among the subjects is
shown in Table 2. Majority of the subjects (47%)
have been working between 2-3 years with Celcom.
The longest duration of service was 8 years in 3
subjects. However, in 18 subjects the duration of
service could not be determined. Therefore, the 18
subjects were excluded from the research.
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R. Mazlan, L. Saim, et. al
Figure 1: Race distribution among the subjects
subjects with hearing impairment were in the early
years of service (2-3 years).
Discussion
Documented instances in which headphones
used by telephonists have been shown to create aural
hygiene problems or are the cause for infections of
the ear canal are rarely described in the literature.
Nevertheless it is not uncommon for telephonists
and other wearers of hearing protective devices to
express concern regarding the potential for the
headphones to cause ear infection.
Our study did not show any evidence of
infection of the external ear canal amongst the 118
customer service representatives examined by the
ENT Surgeons. Observable signs of infection that
were looked for in the ear canal include swelling
and reddening of the ear canal, discharge and foul
odour of the ear canal. Symptoms included itching,
pain and tenderness upon manipulation of the pinna
and a feeling of fullness in the ear. None of the
subjects had any of the above signs and symptoms.
However amongst these subjects, 4 were noted to
have impacted wax. Since this is a cross-sectional
study with no control group, it is not possible to
attribute the occurrence of impacted wax due to the
use of headphones. This low percentage may
represent the prevalence of impacted wax in normal
population. Reports of external ear infection or
impacted wax resulting directly from wearing
headphones are exceedingly rare. Forshaw and
Cruchley reported on a study of 60 long range patrol-
aircraft crew members wearing earplugs, who were
randomly divided into three groups; one wearing
premould earplugs, the second using foam earplugs
washed after each used, and (2) the third using
earplugs washed only once per week (1). The study
lasted 8 weeks and included examinations by
medical officer as well as skin scrapping for bacterial
culture and fungal examinations. The results
indicated no fungal infection or clinically significant
bacterial infections and no differences in positive
bacterial cultures across the three groups of users.
In another study, Cooper reported a study on 587
employees at five mid-western (United State of
America) industrial facilities using otoscopy. The
subjects were divided into premould earplug users,
foam earplugs users and those who did not wear any
device. The prevalence of external ear canal
infections was less than 0.5% across all groups, with
no statistically significant differences among the
groups. Cooper also reported data on the presence
of cerumen. The prevalence of partial cerumen
blockage was 5.0% and total cerumen blockage was
5.1% (3).
Wearing headphones or earplugs has been
suggested as a possible predisposing factor for
external ear canal infection since their use can
increase the temperature and humidity of the canal,
create the potential for skin abrasion and provide a
vehicle for the introduction of organisms into the
canal skin (4). However, as discussed above, our
study does not substantiate concern regarding the
potential for headphones to increase the likelihood
of developing an external ear infection.
We found 4 cases of chronic middle ear
infect ion with perforati on of the tym pani c
21
EAR INFECTION AND HEARING LOSS AMONGST HEADPHONE USERS
Figure 2 : Duration of services among the hearing impaired
subject
membranes. There were 2 active disease and 2
inactive diseases. These were incidental findings. It
was most unlikely that the headphone is the cause
of the middle ear infection without any external ear
canal infection. However, in the 2 subjects with
active chronic middle ear infection, they claimed
that prolonged use of the headphone on the affected
ear may cause itchiness and increased discharge
from the ear. This was expected since it has been
our experience that the use of ear mould for hearing
aids in-patients with chronic middle ear infection
would cause such complications. This finding has
also been reported in other studies (5).
There was also concern amongst these users
of headphones that prolonged use of the device may
cause hearing loss. In this study, we examined the
incidence of hearing impairment in the left and right
ear separately by performing pure tone audiometry.
A strict criteria for hearing impairment is used.
Hearing impairment was defined as having hearing
threshold of more than 20 dB HL in at least one
tested frequency. Twenty-five subjects (21.2%) were
found to have hearing impairment in either one or
both ears. This prevalence was comparable to the
prevalence of hearing loss in normal subjects used
as controls in other studies (6).
The 25 subjects with hearing impairment in
one or both eras were further analyzed to determine
if the hearing impairment was due to noise exposure
from prolonged use of the earphone. As one knows,
no ise in duced heari n g los s affe cts th e 4 kH z
frequency first before further affecting the other
frequencies (7). This study did not show higher
incidence of hearing impairment in the 4 kHz or
other frequencies. In fact the number of subjects with
hearing impairment in the low, mid and high
frequencies were almost equal. Therefore, it was
most unlikely that the use of headphone for a period
of 8 hours per shift by these customer service
representatives would have any effect on the hearing.
This was further strengthened by our findings when
comparing the association between hearing loss and
duration of service. The majority of the subjects with
hearing impairment were in fact in the early years
(2-3 years). Thus, the longer the service and therefore
more prolonged usage of the headphone does not
predispose one to hearing impairment. This finding
was expected since the soun ds from these
headphones are of low intensity. The average
measurement of sound intensity from the headphone
was found to be 58 dB HL. It was generally below
85 dB Hl, which was the threshold above which
prolonged exposure of 8 hours or more which may
caused a permanent hearing loss.
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R. Mazlan, L. Saim, et. al
Conclusion
In this study, prolonged use of the headphones
amongst customer service representatives did not
predispose them to infection of the external ear canal.
However in individuals who already had chronic
middle ear infection, its use could cause increased
itchiness and reactivation of the middle ear infection.
There was also no evidence of noise induced hearing
loss amongst those with prolonged exposure to the
sound from headphones and the duration of service.
Recommendation
Examination of the ear and hearing test should
be performed prior to employment, so that a more
in-depth study can be done to establish or dismiss
the association between the use of headphones and
ear infection or hearing loss. Such examination
should then be done yearly during employment. This
will allow a reasoned approach and help to avoid an
overreaction from the employee if they develop any
ear infection or hearing loss. It is also useful to
suggest regular hygienic wash or cleaning of the
headphone in accordance with manufacturer’s
instruction, to prevent any reservoir of bacteria or
fungus that can cause external canal infection.
Sharing of headphones should be discouraged.
Acknowledgements
We would like to thank Puan Puteri Suraya
Binti Megat Harun and Encik Nuri of Celcom
(Malaysia) Sdn. Bhd. for their fullest cooperation
in conducting this study.
Correspondence:
Puan Rafidah Mazlan
Jabatan Otorinolaringologi, Hospital UKM,
Jalan Yaakob Latif, Bandar Tun Razak
56000 Cheras, Kuala Lumpur.
Tel: 03-9702446, Fax: 03-9737840
References
1. Katz J. Handbook of Clinical Audiology. 4th edition.
Baltimore: Williams and Wilkins, 1984.
2. Forshaw S.E. and Cruchley J.L. “Hearing protector
problems in military opertions” in Personal Hearing
Protection in Industry, edited by P.W. Alberti, Raven
Press, New York, NY, 1982; 387-402.
3. Cooper S.J. “Relationship of hearing protector type
and prevalence of external auditory canal pathology”
presented at the Am. Ind. Hyg. Asso. Conf. Las Vegas,
NV, paper #23, 1985.
4. Senturia B. H., Marcus M.D., and Lucente F.E.
Diseases of the External Ear-An Otologic-
Dormatologic Manual. New York: Grune & Stratton,
1980.
5. Berger E.H. EarLog #17-Ear infection and the use of
hearing protection. Journal of Occupational Medicine
1986; 27 (9): 620-623.
6. Sanusi S. The prevalence of noise induced hearing loss
among radio deejays working with Radio and
Television Malaysia from Dec 1996-Mac 1997. Thesis
submitted for Masters of Surgery (ORL-Head and
Neck) Universiti Kebangsaan Malaysia, 1998.
7. Noise and Hearing Loss. NIH Consensus Statement
Jan 22-24, 1990 ; 8(1):1-24.
