Musculoskeletal disorders among
municipal solid waste collectors in
Mansoura, Egypt: a cross-sectional study
Hala Samir Abou-ElWafa,1 Sohair Fouad El-Bestar,1 Abdel-Hady El-Gilany,1
Ehab El-Sayed Awad2
To cite: Abou-ElWafa HS,
El-Bestar SF, El-Gilany A-H,
et al. Musculoskeletal
disorders among municipal
solid waste collectors in
Mansoura, Egypt: a crosssectional study.
BMJ Open
2012;2:e001338.
doi:10.1136/bmjopen-2012-
001338
Prepublication history and
additional material for this
paper are available online. To
view these files please visit
the journal online (http://dx.
doi.org/10.1136/bmjopen-
2012-001338).
Received 2 May 2012
Accepted 15 August 2012
This final article is available
for use under the terms of
the Creative Commons
Attribution Non-Commercial
2.0 Licence; see
http://bmjopen.bmj.com
1Department of Public Health
and Community Medicine,
Mansoura University,
Mansoura, Egypt
2Department of Internal
Medicine, Mansoura
University, Mansoura, Egypt
Correspondence to
Dr Hala Samir Abou-ElWafa;
[email protected]
ABSTRACT
Objective: To assess the percentage of
musculoskeletal complaints and their possible risk
factors among municipal solid waste (MSW) collectors.
Design: A descriptive cross-sectional study with a
comparison group.
Setting: Primary level of care, at the Western
Municipality of Mansoura City, Egypt.
Participants: A total of 160 male MSW collectors
fulfilled the eligibility criteria and 120 of them
participated in the study (response rate of 75%). The
inclusion criteria were permanent or temporary solid
waste collectors employed for 1 year or more.
A comparison group of 110 male service workers at
the Faculty of Medicine, Mansoura University,
comparable to MSW collectors in most of the
variables.
Outcome: The percentage of musculoskeletal
disorders (MSDs) among collectors, their risk factors
(socio-demographic, psychosocial, physical), and the
independent risk factors for having the disorders.
Results: The percentage of musculoskeletal complaints
during the past 12 months was higher among MSW
collectors (60.8%) than the comparison group (43.6%).
Low back was the most frequently affected body region
among MSW collectors. The differences in the
distribution of musculoskeletal complaints between the
two groups were statistically significant for the neck and
hip/thigh regions. Logistic regression analysis revealed
that the independent risk factors for musculoskeletal
symptoms among MSW collectors were the longer
duration of employment (OR=0.4, 95% CI=0.1 to 0.9);
low decision latitude (OR=0.3, 95% CI=0.1 to 0.7);
lifting, pulling; pushing/carrying loads >20 kg (OR=5.5,
95% CI=1.8 to 17.0) and walking for long periods of
time (OR=2.6, 95% CI=1.1 to 6.6).
Conclusions: Musculoskeletal complaints are highly
prevalent among MSW collectors which require
engineering, medical and legislative measures. We
suggest further research in the interventions that could
reduce the high percentage among collectors.
INTRODUCTION
Human activities create waste, and it is the
way this waste is handled, stored, collected
and disposed of, which can pose risks to the
environment and to public health.
1 One job
that has contributed greatly to human health
by reducing the risk of several diseases like
typhoid fever or cholera is waste collecting.
2
For waste collectors, the risk of disease resulting from exposure to various work hazards is
high,
35 as is the risk of fatal and non-fatal
occupational accidents.
6
Several studies, were conducted upon
municipal solid waste (MSW) collectors to
study their health problems, are worldwide
accessible and published in peer-reviewed
journals.
Association between working environment
and musculoskeletal symptoms has been
widely reported. Workplace activities such as
heavy lifting, manual handling, prolonged
sitting and standing, bending and repetitive
tasks are known as risk factors for musculoskeletal disorders (MSDs).
4 79
Refuse collecting is a physically demanding
job, which is associated with a high prevalence
rate of MSDs.
3 4 1012 Moderate evidence is
available that waste collecting increases the
ARTICLE SUMMARY
Article focus
Manual solid waste collectors are at risk of musculoskeletal disorders (MSDs).
MSDs are multifactorial in nature.
Intervention is needed to reduce the risk.
Key messages
MSDs are highly prevalent among municipal
solid waste (MSW) collectors.
Personal, psychosocial and ergonomic risk
factors are implicated.
Mechanisation of collection minimises the risk.
Strengths and limitations of this study
The first study to be carried out among this
sector.
Single-centre study with small sample size is the
main limitation.
Abou-ElWafa HS, El-Bestar SF, El-Gilany A-H, et al. BMJ Open 2012;2:e001338. doi:10.1136/bmjopen-2012-001338 1
Open Access Research
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risk of respiratory complaints and limited evidence is available for gastrointestinal complaints and hearing loss
according to the systematic review by Kuijer
et al.2
Among waste collectors, non-fatal injuries are mainly
musculoskeletal in nature.
13 In many developing countries, MSW is collected manually and collection of household waste is also a job which requires repeated heavy
physical activity such as lifting, carrying, pulling and
pushing.
14 A nearly 2 times higher incidence rate of musculoskeletal complaints for refuse collectors was reported
in Denmark than for the total Danish workforce.
12 For
refuse collectors in Taiwan, the risks for musculoskeletal
complaints of the low back and elbow/wrist among
refuse collectors were more than two times higher than
those of their colleagues that worked in the of
fice.14
Solid waste management practice in Egypt has been
largely focused on the issues of collection and disposal
with little or no attention paid to the health status of
MSW collectors. The collection methods are based
mostly on manual labour, which is less costly than the
mechanised collection systems adopted in developed
countries. To the authors
best knowledge, no past
studies have investigated the actual prevalence of MSDs
and their risk factors in MSW collectors in Egypt.
The objective of this study was to assess the prevalence
of musculoskeletal symptoms in a group of MSW collectors in Mansoura city and to identify the possible risk
factors contributing to their occurrence.
SUBJECTS AND METHODS
A cross-sectional study with a comparison group was conducted upon solid waste collectors working at the
Western Municipality of Mansoura city during the
period from 1 January to 31 August 2011.
Study population
The at-risk group (MSW collectors)
The total number of solid waste collectors was 198 and
all were men. The inclusion criteria were permanent or
temporary solid waste collectors employed for 1 year or
more. A total of 160 solid waste collectors ful
filled the
eligibility criteria and 120 of them participated in the
study (response rate of 75%). The MSW collectors were
interviewed and examined at three regional assembly
of
fices according to their geographical distribution at
13:00 where collectors of the morning and evening shift
arrive for signing.
Comparison group
The group comprised 110 male service workers at the
Faculty of Medicine, Mansoura University, comparable to
MSW collectors in most of the variables except for the
risk of exposure to MSW.
The comparison group was interviewed and examined
at the Department of Public Health and Community
Medicine during the work day.
Ethical consideration
Approval of the Western Municipality and Faculty of
Medicine authorities was obtained. An informed verbal
consent of study subjects to participate in the study was
obtained with assurance of con
fidentiality and anonymity of the data. Subjects participated voluntarily with a
full right to withdraw from the study. There is no
Research Ethics Committee at the moment.
Study tools
Each participant was subjected to the following:
1. Interview: A questionnaire was used to collect the following data:
A. Socio-demographic and occupational pro
file of
workers.
B. Physical work demands using the Dutch
Musculoskeletal Questionnaire.
15
C. Musculoskeletal symptoms (pain or discomfort
or ache) by body region using Standardised
Nordic questionnaire for the analysis of musculoskeletal symptoms.
16
Risk factors for work-related MSDs were classified into several physical, psychosocial and individual factors according to the results of various
epidemiological studies and literature
reviews.
1719
D. Job strain was measured using job strain index.20
Psychological job demands were measured using
five items with four response alternatives each,
forming a four-point ordinal scale. An index of
psychological job demands was formed by the
sum of scores for these items, with 5 as the
minimum and 20 as the maximum score for the
index. In a corresponding way, decision latitude
was measured by an index based on six items,
with 6 as the minimum and 24 as the maximum.
Decision latitude and psychological job demands
were dichotomised into
highand low, using
the median score as the cut-off point (18 for
decision latitude and 13 for job demands).
2. Clinical examination.
3. Anthropometric measurements: weight and height
were measured, and body mass index (BMI) was calculated. Obesity was de
fined as BMI30.00 kg/m2.21
Data analysis
Data were entered, cleaned and statistically analysed
using the SPSS V.16.
Qualitative variables were described as numbers and
percentages.
χ2 and Fishers exact test were used for
comparison between groups; as appropriate.
Quantitative variables were described as mean (±SD)
and median. They were tested for normality by
Kolmogorov-Smirnov test. In the normally distributed
variables, independent sample t test was used; while in
non-normally distributed variables, Mann-Whitney test
was used for comparison between groups.
2 Abou-ElWafa HS, El-Bestar SF, El-Gilany A-H, et al. BMJ Open 2012;2:e001338. doi:10.1136/bmjopen-2012-001338
Musculoskeletal disorders among municipal solid waste collectors
BMJ Open: first published as 10.1136/bmjopen-2012-001338 on 12 September 2012. Downloaded from http://bmjopen.bmj.com/ on October 7, 2019 by guest. Protected by copyright.
Binary stepwise logistic regression analysis was used for
prediction of independent variables. Signi
ficant predictors for MSDs in the bivariate analysis were entered into
the regression model. ORs and their 95% CI were calculated. A p
0.05 was considered to be statistically
signi
ficant.
RESULTS
Socio-demographic characteristics
Table 1 shows that MSW collectors were comparable
with the comparison group in most of the sociodemographic characteristics except for the family size
and residence. The majority of both MSW collectors and
comparison group (78.3% and 68.2%, respectively) were
above the age of 40. Most of the MSW collectors
(89.2%) were illiterate/read and write compared to
82.7% of the comparison group. The percentage of
obesity was 16.7% in the MSW collectors compared to
25.5% of the comparison group (p>0.05).
Operational definition
Enough means that their income meets their daily needs;
while
indebt means that their income is not satisfactory.
Occupational profile of the study groups
Table 2 shows that the majority of both MSW collectors
(71.7%) and the comparison group (79.1%) were
temporary workers. MSW collectors were employed for
longer duration than the comparison group (15 vs
11 years). Most of the MSW collectors (81.7%)
collected waste using a local collection unit (offa) with a
median weight of 20 kg and 33.6% of the comparison
group used baskets with a median weight of 6 kg. MSW
collectors collected waste from all sources using mainly
tractors and trucks. However, the comparison group collected waste mainly from commercial and institutional
sources using tractors and vehicles with mobile bins. The
differences between both groups regarding the collection
vehicle, weight of the collection unit and sources of collected waste were statistically signi
ficant. Most of MSW
collectors (96.7%) and 70.9% of the comparison group
had high job demands with statistically signi
ficant
difference.
Percentage and anatomical distribution of musculoskeletal
complaints
Table 3 reveals that the percentage of musculoskeletal
complaints during the past 12 months was signi
ficantly
higher among MSW collectors (60.8%) compared to
43.6% of the comparison group (p
0.01).
The anatomical distribution of musculoskeletal complaints among MSW collectors showed that: the most frequently affected body regions were low back (22.5%);
then shoulders (15.8%); neck (7.5%); knee (6.7%) and
hips/thighs and elbows (5.8% each). However, among
Table 1 Socio-demographic profile of the study groups
MSW collectors Comparison group
Test of significance
n=120 n=110
n (%) n (%)
Age (years)
<40 26 (21.7) 35 (31.8)
χ2=3.03, p>0.05
40 94 (78.3) 75 (68.2)
Mean±SD 47.4±9.7 ys 45.5±7.5ys t=1.7, p>0.05
Level of education
Illiterate/read and write 107 (89.2) 91 (82.7)
χ2=1.9, p>0.05
Primary and others 13 (10.8) 19 (17.3)
Marital status
Unmarried 2 (1.7) 6 (5.5)
χ2=2.5, p>0.05
Married 118 (98.3) 104 (94.5)
Family size
<5 persons 22 (18.3) 71 (64.5)
χ2=50.9, p0.001
5 persons 98 (81.7) 39 (35.5)
Family income per month*
Enough 57 (47.5) 66 (60.0)
χ2=3.6, p>0.05
Indebt 63 (52.5) 44 (40.0)
Residence
Rural 114 (95.0) 84 (76.4)
χ2=16.6, p0.001
Urban 6 (5.0) 26 (23.6)
BMI groups
Underweight 4 (3.3) 2 (1.8) Non-obese versus obese
Normal weight 67 (55.8) 54 (49.1)
Overweight 29 (24.2) 26 (23.6)
χ2=2.7, p>0.05
Obese 20 (16.7) 28 (25.5)
*It is based on subjective term.
Abou-ElWafa HS, El-Bestar SF, El-Gilany A-H, et al. BMJ Open 2012;2:e001338. doi:10.1136/bmjopen-2012-001338 3
Musculoskeletal disorders among municipal solid waste collectors
BMJ Open: first published as 10.1136/bmjopen-2012-001338 on 12 September 2012. Downloaded from http://bmjopen.bmj.com/ on October 7, 2019 by guest. Protected by copyright.
the comparison group, the most frequently affected
body region was low back (19.1%); then shoulders
(8.2%); upper back (7.3%) and knee and elbows (4.5%
each).
Risk factors for musculoskeletal symptoms
Table 4 shows that, the difference between MSW collectors with musculoskeletal symptoms and those free of
symptoms was statistically signi
ficant (p0.01) regarding
Table 2 Occupational profile of the study groups
MSW collectors Comparison group
Test of significance
n=120 n=110
n (%) n (%)
Type of contract
Temporary 86 (71.7) 87 (79.1)
χ2=1.7, p>0.05
Permanent 34 (28.3) 23 (20.9)
Duration of employment (years)
Median (min
max) 15 (136) years 11 (131) ys Z=1.8, p>0.05
Sources of collected waste*
Residential 111 (92.5) 0 (0.0)
χ2=196.7, p0.001
Commercial 109 (90.8) 76 (69.1)
χ2=17.2, p0.001
Industrial 105 (87.5) 0 (0.0)
χ2=177.1, p0.001
Institutional 105 (87.5) 74 (67.3)
χ2=13.6, p0.001
Biomedical 105 (87.5) 7 (6.4)
χ2=151.2, p0.001
Collection vehicle

Tractor 64 (53.3) 56 (50.9) Tractor versus others
Trolley 5 (4.2) 1 (0.9)
χ2=7.4, p0.01
Truck 35 (29.2) 0 (0.0)
Vehicle with mobile bin 16 (13.3) 20 (18.2)
Collection unit

Waste basket 2 (1.7) 37 (33.6) Non-wheeled versus wheeled containers
Waste bag 6 (5) 24 (21.8)
Offa (a local collection bag) 98 (81.7) 0 (0.0)
χ2=3.02, p>0.05
Two-wheeled container 14 (11.7) 4 (3.6)
Four-wheeled container 0 (0.0) 12 (10.9)
Weight of collection unit in kg
(Median (min
max))
20 (7
70) 6 (150) Z=7.3, p0.001
Job demands
High (
13) 116 (96.7) 78 (70.9)
χ2=28.8, p0.001
Low (>13) 4 (3.3) 32 (29.1)
Decision latitude
High (
18) 68 (56.7) 76 (69.1)
χ2=3.8, p>0.05
Low (>18) 52 (43.3) 34 (30.9)
*Categories are not mutually exclusive.
Non-wheeled containers include waste basket, bag and offa; wheeled containers include two-wheeled and four-wheeled containers.
Only 77 of the comparison group collect waste.
Table 3 Anatomical distribution of musculoskeletal complaints among the study groups in the past 12 months
MSW collectors Comparison group
Test of significance
n=120 n=110
n (%) n (%)
No complaint 47 (39.2) 62 (56.4)
χ2=6.8, p0.01
One or more complaints 73 (60.8) 48 (43.6)
Neck 9 (7.5) 2 (1.8)
χ2=4.1, p0.05
Shoulders 19 (15.8) 9 (8.2)
χ2=3.1, p>0.05
Elbow 7 (5.8) 5 (4.5)
χ2=0.19, p>0.05
Wrists/hands 2 (1.7) 2 (1.8) Fisher
s exact, p>0.05
Upper back 4 (3.3) 8 (7.3)
χ2=1.8, p>0.05
Low back 27 (22.5) 21 (19.1)
χ2=0.4, p>0.05
Hips/thighs 7 (5.8) 0 (0.0) Fisher
s exact, p0.01
Knee 8 (6.7) 5 (4.5)
χ2=0.5, p>0.05
Ankles/feet 4 (3.3) 1 (0.9) Fisher
s exact, p>0.05
4 Abou-ElWafa HS, El-Bestar SF, El-Gilany A-H, et al. BMJ Open 2012;2:e001338. doi:10.1136/bmjopen-2012-001338
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BMJ Open: first published as 10.1136/bmjopen-2012-001338 on 12 September 2012. Downloaded from http://bmjopen.bmj.com/ on October 7, 2019 by guest. Protected by copyright.
Table 4 Risk factors for musculoskeletal symptoms in MSW collectors
Musculoskeletal symptoms
Test of significance

Present n=73
n (%)
Absent n=47
n (%)

I. Socio-demographic factors
Age (years)
<40 14 (19.2) 12 (25.5)
χ2=0.7, p>0.05
40 (r) 59 (80.8) 35 (74.5) OR 0.69 (0.3, 1.8)
Duration of employment in years
<15 26 (35.6) 27 (57.4)
χ2=5.5, p0.01
15 (r) 47 (64.4) 20 (42.6) OR 0.4 (0.2, 0.9)
BMI
Non-obese 58 (79.5) 42 (89.4)
χ2=2, p>0.05
Obese (r) 15 (20.5) 5 (10.6) OR 0.5 (0.1, 1.5)
II. Psychosocial factors:
Job demands
High (
13) 71 (97.3) 45 (95.7) Fishers exact, p>0.05
Low (>13) (r) 2 (2.7) 2 (4.3) OR 1.6 (0.2, 16.4)
Decision latitude
High (
18) 32 (43.8) 36 (76.6) χ2=12.5, p0.001
Low (>18) (r) 41 (56.2) 11 (23.4) OR 0.2 (0.1, 0.6)
III. Physical work demands:
Lift, push, pull or carry loads >5 kg 57 (78.0) 32 (68.0)
χ2=1.5, p>0.05
OR 1.7 (0.7, 4.1)
Lift, pull, push or carry loads >20 kg 56 (76.7) 26 (55.3)
χ2=6, p0.01
OR 2.7 (1.1, 6.3)
Exert great force on tools 2 (2.7) 2 (4.3) Fisher
s exact, p>0.05
OR 0.6 (0.1, 6.6)
Bent or twist with trunk 58 (79.5) 32 (68.0)
χ2=1.9, p>0.05
OR 1.8 (0.7, 4.5)
Bent or twist with neck 55 (75.3) 30 (63.8)
χ2=1.8, p>0.05
OR 1.7 (0.7, 4.2)
Bent or twist with wrists/hands 57 (78.0) 33 (70.2)
χ2=0.9, p>0.05
OR 1.5 (0.6, 3.8)
Bent, or twisted posture for long periods of time with trunk 51 (69.9) 31 (66.0)
χ2=0.2, p>0.05
OR 1.2 (0.5, 2.8)
Bent, or twisted posture for long periods of time with neck 46 (63.0) 30 (63.8)
χ2=0.01, p>0.05
OR 0.9 (0.4, 2.2)
Bent, or twisted posture for long periods of time with wrists 44 (60.3) 31 (66.0)
χ2=0.4, p>0.05
OR 0.8 (0.3, 1.8)
Make short repetitive movements with trunk 8 (11.0) 0 (0.0) Fisher
s exact, p0.01
Make short repetitive movements with neck 6 (8.2) 0 (0.0) Fisher
s exact, p0.05
Make short repetitive movements with wrists 12 (16.4) 0 (0.0) Fisher
s exact, p0.001
Reach with arms or hands 4 (5.5) 0 (0.0) Fisher
s exact, p>0.05
Hold arms at or above shoulder level 24 (32.9) 16 (34.0)
χ2=0.02, p>0.05
OR 0.9 (0.4, 2.2)
Work in uncomfortable postures 37 (50.7) 25 (53.2)
χ2=0.1, p>0.05
OR 0.9 (0.4, 2)
Work in the same posture for long periods of time 49 (67.0) 36 (76.6)
χ2=1.2, p>0.05
OR 0.6 (0.2, 1.5)
Make frequent repetitive movements with arms, hands or fingers 29 (39.7) 27 (57.4)
χ2=3.6, p0.05
OR 0.5 (0.2
1.1)
Stand for long periods of time 46 (63.0) 32 (68.0)
χ2=0.3, p>0.05
OR 0.8 (0.3
1.8)
Sit for long periods of time 1 (1.4) 6 (12.8) Fisher
s exact, p0.01
OR 0.1 (0.0, 0.8)
Walk for long periods of time 65 (89.0) 30 (63.8)
χ2=11, p0.001
OR 4.6 (1.6, 13.2)
BMI, body mass index; r, reference category.
Abou-ElWafa HS, El-Bestar SF, El-Gilany A-H, et al. BMJ Open 2012;2:e001338. doi:10.1136/bmjopen-2012-001338 5
Musculoskeletal disorders among municipal solid waste collectors
BMJ Open: first published as 10.1136/bmjopen-2012-001338 on 12 September 2012. Downloaded from http://bmjopen.bmj.com/ on October 7, 2019 by guest. Protected by copyright.
the duration of employment. Most of MSW collectors
without musculoskeletal symptoms (76.6%) had signi
ficantly high decision latitude compared to only 43.8% of
those with symptoms (p
0.001). The difference
between both groups was statistically signi
ficant regarding lift, pull, push or carry loads >20 kg; make short
repetitive movements with trunk; neck; wrists; and arms,
hands or
fingers; sit and walk for long periods of time.
Independent risk factors for musculoskeletal symptoms
Logistic regression analysis showed that the short duration of employment as waste collector and the high
decision latitude were associated with low risk of MSDs
(OR=0.4 and 0.3, respectively). On the other hand,
lifting, pulling, pushing or carrying loads >20 kg, and
walking for long periods of time were independently
associated with the likelihood of having musculoskeletal
symptoms (OR=5.5 and 2.6, respectively) (
table 5).
DISCUSSION
Prevalence and risk factors
The results of the present study showed that a high percentage of musculoskeletal complaints (60.8%) was
detected among MSW collectors and the low back was
the most frequently affected body region. The independent risk factors for musculoskeletal symptoms among
MSW collectors were the duration of employment; decision latitude; lifting, pulling; pushing/carrying loads
>20 kg and walking for long periods of time.
The most frequently affected body regions among
MSW collectors were low back (22.5%); then shoulders
(15.8%); neck (7.5%); knee (6.7%) and hips/thighs
and elbows (5.8% each). The differences in the distribution of musculoskeletal complaints between MSW
collectors and the comparison group were statistically
signi
ficant for the neck and hips/thighs regions.
In Egypt, collectors suffer from MSDs because of the
large volume of waste they have to pack manually.
Ergonomic risk factors are contributing factors. The illiterate collectors may be unaware about the proper safety
techniques during waste collection.
In Palestine, 45.7% of surveyed waste collectors have
suffered from backache, 34.1% of waste collectors have
suffered from twisted ankle, 22.1% have suffered from
muscle tear, 8.7% have suffered from joint pain.
Regarding the cause of the injured part of the body in
the last 12 months, 61.1% of waste collectors have been
hit by any hard or sharp objects, 37.4% have lifted more
than their capacity, 35.6% have fallen down while pulling
or pushing the waste trolley, and 21.6% of waste collectors
have been stuck with hard object. Nearly half of the waste
collectors (44%) were satis
fied with their job and 21.1%
were very satis
fied with their work, while 17.7% and
14.8% of domestic waste collectors surveyed were not satis
fied to absolutely not satisfied, respectively.22
In Nigeria, 171 workers representing 61.3% of the
sampled solid waste collectors had suffered from musculoskeletal injuries on the job. Solid waste collectors in
Port Harcourt municipality suffered from musculoskeletal injuries because of the large volume of wastes they
have to pack manually in contrast to the use of hydraulic
lifts.
23
In Iran, prevalence of musculoskeletal symptoms,
among MSW workers in Tehran, in low back, knees,
shoulders, upper back and neck were 45%, 29%, 24%,
23% and 22%, respectively. The study found that solid
waste workers had more MSDs than the general population. The risk of disease was increased with the increasing years of working as solid waste worker and smoking.
There was no relationship between MSDs and education
or marriage status of workers.
24
High prevalence of MSDs among refuse collectors was
reported in Brazil,
25 Denmark,12 26 Taiwan,14 USA13 27
and the Netherlands.28
In developed countries, automated trucks are used
using hydraulic lift to pick up and dump trash containers.
23 In Egypt, the reverse is the case. In many developing countries, MSW is collected manually and collection
of household waste is also a job which requires repeated
heavy physical activity such as lifting, carrying, pulling
and pushing.
14
MSW collectors and the comparison group were of
low socioeconomic status as the majority of them had
low educational levels, insuf
ficient family income with
large family size and were rural residents. In Egypt,
waste collectors are subject to social stigma, they are
likely to be from marginalised groups. Manual waste collection is easily learned and usually does not require literacy or vocational training. This job provides a source
of livelihood to extremely poor people. MSW collectors
are considered the poorest of the poor. Many people
view waste collectors as a nuisance or source of shame.
Table 5 Logistic regression analysis of independent risk
factors for musculoskeletal symptoms among MSW
collectors
β p Value OR (95% CI)
Duration of employment (years)

<15
15 (r)
Decision latitude
1.01 p0.05
High
Low (r)
1.3 p0.01
Lift, pull, push or carry loads >20 kg
Yes
No (r)
1.7 p0.01
Walk for long periods of time
Yes
No (r)
Constant
Model
χ2
Percentage correctly
0.97 p0.05
0.3
32.0, p0.001
70

predicted
r, reference group.
6 Abou-ElWafa HS, El-Bestar SF, El-Gilany A-H, et al. BMJ Open 2012;2:e001338. doi:10.1136/bmjopen-2012-001338
Musculoskeletal disorders among municipal solid waste collectors
BMJ Open: first published as 10.1136/bmjopen-2012-001338 on 12 September 2012. Downloaded from http://bmjopen.bmj.com/ on October 7, 2019 by guest. Protected by copyright.
In India, it was concluded that the social stigma of waste
pickers remains a problematic issue.
29 It was commented
that the socioeconomic status of the waste collectors is
low, and their working conditions are unfavourable.
30
Even in Japan, the discrimination against waste management workers still exists.31 The lower socioeconomic
status of MSW collectors was reported in Palestine
22 and
Nigeria as most of the workers admitted to doing it as a
last resort in the absence of better alternative.
23
All of MSW collectors were men and the majority of
both groups were in the middle-age groups. The same
findings were reported from Palestine and Nigeria.22 23
It was concluded that formal waste collection is mainly
performed by male employees.
6 Waste collection in
Egypt uses old and traditional equipment and depends
on the physical power of the collectors.
Most of MSW collectors had high job demands and
about half of them (56.7%) had high latitude. This could
be attributed to nature of their contract. The majority of
both groups were temporary workers. Temporary collectors are excluded from the social and health insurance.
The daily paid labourers have no bene
fits or job security.
Thus, they are under physical and psychological
demands with lack of job satisfaction. Work satisfaction is
an important parameter to do a perfect job.
The work of waste collectors is characterised by an
abundance of heavy lifting as well as pulling and
pushing of containers and carts. In addition, the work of
waste collectors may contain work above shoulder level,
frequent exertion of force, static contractions and
extreme joint positions which are occupational risk
factors for MSDs of the neck, shoulders and arms.
3234
Measures to prevent MSDs
The following measures to prevent MSDs among refuse
collectors have been evaluated and seem to be effective:
Job-specific guideline for refuse collectors regarding
maximum production limits (maximum amount of
waste (or a maximum number of bags/containers) and
a maximum number of hours that waste collecting
tasks may be performed during an 8 h working day).
11
Job rotation between collecting bags, sweeping streets
and driving a sweeping machine.
35
Job rotation between collecting two-wheeled containers and driving a refuse truck.28
A major economic benefit of job rotation is the
increase in
flexibility. Several studies have indicated possible ergonomic benefits of job rotation in reducing the
risk of musculoskeletal complaints.
36 37
Kuijer et al35 conducted a study at a refuse collecting
company, the introduction of job rotation among collecting bags, sweeping streets and driving a small cleansing machine seemed to result in a marked reduction in
physical workload. Kuijer and Frings-Dresen
6 showed
that the introduction of job rotation between collecting
two-wheeled containers and driving the refuse truck
resulted in a decrease of the physical work demands and
physical workload of refuse collecting.
Replacement of bags and bins with wheeled
containers.
4 10
Removing obstacles at places where wheeled containers are collected.38
Transferring a four-wheeled container by two persons
instead of one.
10
At least a 10 min rest break per hour while collecting
four-wheeled containers.
39
Collectors should briefly test the weight of each container before lifting, to prepare for the load and they
should not mount trucks while moving.
40
Develop training materials on occupational and environmental health and injury issues relating to solid
waste management for staff at all levels.
41
Incentives for safety compliance should be maintained
and advertised and compensation should be evaluated
relative to disease frequency.
40
These measures could be applied to reduce MSDs
among MSW collectors; they are applicable and to some
extent affordable.
Role of physicians in the prevention and control of MSDs
Physicians could have a role in the prevention and
control of MSDs among MSW collectors which could
be achieved through health education of workers
about early signs of MSDs and when to seek medical
advice, provide training to improve the workers
ability
to avoid musculoskeletal problems, assist in consultation when planning for new work activities, and implementation of the occupational health programme for
their prevention.
Study limitations: This is a single-centre study that
included a small number of MSW collectors with relatively low response rate (75%). Because of the small size
of the study sample, the results cannot be generalised to
the total population of MSW collectors.
In conclusion, MSW collectors are among the most
highly exposed occupational groups with respect to
MSDs. The higher percentage of musculoskeletal symptoms among MSW collectors could be attributed to the
long duration of employment, the low job control and
the nature of their job which is physically demanding
and involves lifting, pulling, pushing heavy loads and
walking for long distances during their daily work along
the designated routes. Also the less educated collectors
seem to be less aware of the potential hazards and
health impacts related to the collection methods. The
unfavourable working conditions of MSW collectors
could be ameliorated through engineering, medical and
legislative measures. Provision of trucks with hydraulic
lifts for packing of refuse will ease the job for the workers
and reduces the incidence of musculoskeletal pains.
Refuse collectors should undergo periodic health examination since occupational demands are still present in
their jobs. The pace of work and opportunities for rest
and recovery should be considered when assessing the
risk of MSDs. There is a need for safety training and
education of collectors on safe handling and lifting
Abou-ElWafa HS, El-Bestar SF, El-Gilany A-H, et al. BMJ Open 2012;2:e001338. doi:10.1136/bmjopen-2012-001338 7
Musculoskeletal disorders among municipal solid waste collectors
BMJ Open: first published as 10.1136/bmjopen-2012-001338 on 12 September 2012. Downloaded from http://bmjopen.bmj.com/ on October 7, 2019 by guest. Protected by copyright.
techniques. Awareness campaigns may change the social
aspects of waste collectors.
Contributors HA-E conception of the research idea and data collection. S E-B:
drafting of the manuscript and revising it for intellectual content. A-HE-G: data
analysis and interpretation and drafting manuscript. EE-SA: clinical
examination of study subjects and critical revising of the manuscript. All
authors revised manuscript and approved its contents.
Competing interests None.
Ethics approval Western Municipality and Faculty of Medicine authorities.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement There is no additional data available.
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8 Abou-ElWafa HS, El-Bestar SF, El-Gilany A-H, et al. BMJ Open 2012;2:e001338. doi:10.1136/bmjopen-2012-001338
Musculoskeletal disorders among municipal solid waste collectors
BMJ Open: first published as 10.1136/bmjopen-2012-001338 on 12 September 2012. Downloaded from http://bmjopen.bmj.com/ on October 7, 2019 by guest. Protected by copyright.