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AMERICAN RESEARCH THOUGHTS
Volume 1 │ Issue 5 │ March 2015
ISSN: 2392 – 876X
Available online at: www.researchthoughts.us
Impact Factor: 2.0178 (UIF)
EFFECTS OF OCCUPATIONAL EXPOSURE TO
SMOKE AND DUSTS IN BRICK KILN
OCCUPANTS
Sami Ullah1, Ayaz Ali Khan2, Kalsoom Ul Haq1, Ghulam Nabi3i
Department of Zoology, University of Malakand, Khyber Pakhtunkhwa, Pakistan
1
Department of Biotechnology, University of Malakand, Khyber Pakhtunkhwa, Pakistan
2
Neuro-Endocrinology Lab, Department of Animal Sciences, Quaid-i-Azam University,
3
Islamabad, Pakistan
Abstract: Brick making is a predominantly rural industry. The burning of fuel for firing bricks
results in emissions of gaseous pollutants and ash into the environment. In present study, ill effects of
these toxicants on the health status of brick kiln occupants were studied. Blood samples along with
histories were taken from brick kiln occupant and control people living in the same locality but are not
frequently exposed to brick kiln dust and smoke. Sysmex KX-21 (Japan) and Shimadzu Double Beam
Spectrometer 1700 Pharma (Japan) were used for blood profiling and blood biochemistry. In workers,
the blood cholesterol level was 204±6.2 mg/dl, triglyceride 203±4.94 mg/dl, serum glutamate pyruvate
transaminase (SGPT) was 53±1.7 U/L, and glucose was 176±1.8 mg/dl. Complete blood count was
also performed for both the workers and control group. In workers, the total red blood cells count was
3.7±0.56 mil/cmm, total leucocytes count 7097±1004/cmm, hemoglobin level 13±1.5 gm/dl,
hematocrit 39±3.9 %, mean corpuscular volume 81±3.6 fl, mean corpuscular hemoglobin
concentration 29±2.5 %, neutrophil count 65.2±4.3 %, lymphocyte 50±4.2 %, and platelets count was
245600±41500/cmm. The results of the control were in normal reference range. The results showed
that there was significant increase in blood biochemical parameters as well as decrease in complete
blood count in the people who were exposed to brick kiln smoke, dust and heat. The result suggests
that these workers are at more risk to chronic bronchitis, decreased lung function, asthma,
pharyngitis, and fibrosis.
Key Words: Brick kiln smoke, Complete blood count, Cholesterol, Triglyceride, Glucose.
i
*Corresponding Author: ghulamnabiqau@gmail.com
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Sami Ullah, Ayaz Ali Khan, Kalsoom Ul Haq, Ghulam Nabi- EFFECTS OF OCCUPATIONAL EXPOSURE TO
SMOKE AND DUSTS IN BRICK KILN OCCUPANTS
1.
INTRODUCTION
Brick manufacturing plant uses many different raw materials and produces many
intermediates by-products and products. Hazardous dust is one of the most important
exposures in brick kiln workers. There are only few published studies on the respiratory
health of brick kiln workers and these have showed that chronic bronchitis and
decreased lung function values are associated with atmospheric pollution, especially in
the firing and unloading section (Huang and Meng, 2000; Myers et al., 2006; Alam and
Starr, 2009). Brick is a very important building material for a developing country
(Mitha et al., 1989).The brick kiln industry is the largest producer in the world, has more
than 73,000 operating units, producing about 900 billion sintered bricks annually,
among which about 50% are fired clay bricks (Wang et al., 2010). The brick kiln emits
huge quantity of toxic elements causing serious health hazards. Emission from brick
kilns comprises of fine dust particles, hydrocarbons, Sulphur Dioxide (SO2), Oxides of
Nitrogen (NOx), Fluoride compounds, Carbon Monoxide (CO) and small amount of
carcinogenic dioxins if rubber tires are used as fuel. Studies showed that inhalation of
even relatively low concentrations of fine particles could affect lung function and lead
to increases in cardiovascular and respiratory diseases (Joshi and Dudani, 2008).
Pakistan, like many developing countries in the world has no comprehensive
Occupational Health and Safety Laws. The incidents of injuries, illness is very high in
Pakistan as thousands of workers are exposed to hazardous chemicals and fumes in
industry (Ambreen, 2012). The brick kiln sector emits the huge quantity of toxic gases
(Iqbal, 2006). Brick workers are exposed to the sun for long hours and exposed to the
high concentration of dust. There is also risk of exposure to the dust and open coal
during manual coal feeding. The workers have to walk on hot surface while monitoring
and regulating the fire (Monga et al., 2012). These main chemical components are
(SiO2), (Al2O3),(Fe2O3). Work exposure to the high temperature and the high density
dust and particulate matter over a long time can result in occupational health problems
e.g. lung cancer (Myers et al., 2006). In Pakistan due to a number of factors, such as
inadequate medical facilities, illiterate workforce and deficiency of reliable data about
productivity and economic prosperity the health in workers are affected negatively
(Pasha, 2003). According to the International Labor Organization (ILO) recent estimates,
160-270 million workers suffer from occupational diseases of accidents every year
(Ambreen, 2012). The increased bondage in brick kiln industry for work up to 12-14
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AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 5 │2015
hours a day is due to employment on flat rate basis, for the number of bricks produced
only and not any wages during illness or injury. A group of professional is affected with
chronic illnesses, black cough and T.B infections in Khyber Pakhtunkhwa (HRW, 1995).
Brick kiln workers are affected with chronic bronchitis with occupational exposures to
dust and smoke. Possible explanation for these high frequencies of respiratory
symptom in brick kiln workers is higher exposure to air pollutants (Neghab and
Choobineh, 2007).
The present study was designed to investigate the effect of brick kilning on the
health status of the workers. No such study has been conducted on this aspect in
Pakistan in general and Khyber Pakhtunkhwa in particular. For this purpose, a printed
questionnaire was filled from workers to take history and also blood samples were
taken from the workers engaged in this occupation. Also, the same procedure was
adopted for control people who were not engaged in this occupation but living all
around the brick kilning industry. The findings of the study are helpful in estimating
the risk of workers to certain diseases and also these people should be aware to prevent
their selves from these diseases. The specific objectives of this study were (1) to check
the ill effects of brick kilning on the health of workers. (2) To investigate the
hematological and blood biochemical abnormalities in the workers. (3) To give
awareness to the workers for protection from the hazardous substance exposure during
working hours. (4) To give proper recommendation to Environmental Protection
Agency (EPA) as well as Public Health Department to ensure the implementation of
safety and health rules in such occupation.
2.
MATERIALS AND METHODS
Sampling area
The visit of sampling area (Gogdara), at Mingora Swat, Khyber Pakhtunkhawa,
Pakistan, was made in October 2012. During visit, primary data and blood samples
from Brick kiln occupants and the people living all around the area were collected.
Number of samples
The samples were collected from 10 workers working in brick kiln and 5 control people.
A standard questionnaire was designed regarding their socioeconomic and health
status.
1513
Blood sampling
A 5ml blood was collected from the brachial vein of each worker and control. Blood
pressure and body temperature were recorded. A 3 ml blood was transferred to
vacutainer tube containing heparin for complete blood profile using Sysmex KX21(Japan). The 2ml blood was transferred to falcon tube having no anticoagulant for the
isolation of serum and then the samples were transferred to -20 °C for later analysis.
Serum was used for analysis of different chemicals (Cholesterol, Glucose, SGPT and
Triglycerides using Shiamadzu Double Beam Spectrophotometer 1700 pharma (Japan).
Data analysis
The data obtained was statistically analyzed. Mean, Standard deviation, column
statistics, T test and row statistics were performed for each parameter. Graph pad
Prism, Demo version 5.0 was used. (www.graphpad.com) for analysis.
2.
RESULTS AND DISCUSSION
History of workers and control group
In the present study, both workers and control group were divided into different age
groups and a questionnaire was designed in which the histories of each group were
taken. Controls were mostly normal while workers were occupationally exposed to
brick kiln toxicants and had some health problems like hypertension, chronic lungs
abnormalities, chest pain, joints pain, allergy and physical weakness. Kodgul and Salvi,
2012 and Nabi et al., 2014 also mentioned that the children, women, elderly peoples and
Tandoor occupants who spent most of their time indoors are at high risk of getting both
the upper as well as lower respiratory tract infection. The data has been given in Table 1
and 2 respectively.
Blood biochemical parameters
1.
Blood cholesterol level
In the present study, serum samples of both groups were analyzed for cholesterol level.
The mean along with standard deviation for both brick making workers and control
have been given in Table 3. In workers, the serum cholesterol level was 204 ± 6.2 mg/dl
with a range of 192 to 210 mg/dl and that of control was 166 ± 16 mg/dl with a range of
147 to 187 mg/dl. The results indicates that in workers there was a significant increase in
1514
serum cholesterol level (P<0.05) as compared to control group. Our results are in
agreement with the findings of Bareegard et al., 2006; Nemmar et al., 2006 and Nabi et
al., 2014 who found high cholesterol level and blood pressure in people exposed to
chronic smoke.
2.
Blood glucose level
In our study the mean along with standard deviation of glucose for workers and control
has been shown in Table 3. The mean value of glucose for workers was 176 ± 1.8 mg/dl
with a range of 173 to 179 mg/dl. The glucose level for control was 79 ± 18 mg/dl with a
range of 68 to 95 mg/dl. There was significant increase (P<0.05) in glucose level of
workers as compared to control group. Our results are in agreement with the findings
of Nabi et al., 2014 who found significantly highly glucose level in Tandoor occupants,
which are frequently exposed to wood smoke and particulate matter as compared to
control group. Similarly Frati et al., 1996 also concluded that exposure to cigarette
smoking also alter glucose level. Also Bornemisza and Suciu, 1980 and Nabi et al., 2014
reported significantly high glucose level in workers exposed to chronic smoke.
3.
Blood triglyceride level
The mean ± standard deviation of triglycerides level for both workers and controls has
been shown in Table 3. The mean along with standard deviation of brick making
workers was 203 ± 4.94 mg/dl with a range of 195 to 210 mg/dl and that of control was
143 ± 22mg/dl with a range of 115 to 171 mg/dl. The difference between the triglyceride
level of workers and control shows that smoke and dust significantly (P<0.05) increases
triglyceride level in workers as compared to control group. Like our study, the findings
of Alokail et al., 2011 showed that infuriate smoke exposure was associated with
increased level of triglycerides. Similarly, Nabi et al., 2014 also found a close association
between chronic wood smoke exposure and increased plasma triglycerides level.
Similar to our findings American Heart Association, 1983 and Frati et al., 1996 also
concluded that cigarette smoking increases triglycerides and blood pressure.
4.
Serum glutamate pyruvate transaminase (SGPT)
The blood samples were also analyzed for SGPT level. The mean with standard
deviation of workers was 53±1.7 U/L with a range 50 to 55 U/L and that of control was
23 ± 6.7 U/L and their range was from 17 to 29 U/L (Table 4). The result showed that
1515
there was significant (P>0.05) increased in SGPT of workers and control group. This
study is in agreement with the results of Nabi et al., 2014 who found a significant
increase in the SGPT level of workers exposed to chronic wood smoke and particulate
matter. Wang et al., 2002 and Loh et al., 2006 also found an increased in the level of
SGPT in individuals exposed to smoke.
5.
Blood profile
Complete blood profile was done for brick making workers and also for control and
results have been in table 4.
a. Hemoglobin (HB) level
The result for Hb has been presented in Table 4. The mean±SD for worker groups was
13 ±1.5 gm/dl having a range of 11 to 16 gm/dl. The same value for control was 13 ± 1.6
gm/dl with a range 12 to 15 gm/dl. There was no significant (P<0.05) difference in the
hemoglobin level of workers as compared to control group. Our results show deviation
from the findings of Nordenberg et al., 1990 and Nabi et al., 2014 which might be due to
differences in the type of fuel used for combustion.
b. Hematocrit (HCT) value
The mean and standard deviation of brick making workers was 36 ±2.9 % with a range
of 31 to 39% and that in control was 43 ± 1.7 % and its range was 40 to 45%. The results
showed that there was significant (P<0.05) decreased in the HCT value of brick making
workers as compared to control (Table 4). This low HCT value is not supported by the
findings of Kondo et al., 1993 and Nabi et al., 2014 who reported high HCT value in
people exposed to smoke which might be due to differences in the type of fuel used.
c. Mean corpuscular volume (MCV)
The mean with standard deviation of MCV in workers was 81 ± 3.6 fl with a range of 74
to 85 fl and the value for control was 97 ± 4.7 fl with a range of 91 to102 fl. The results
showed that there was a significant (P<0.05) difference in the MCV of both workers and
control as shown in Table 4. Our results are against the findings of Kondo et al., 1993
and Nabi et al., 2014 who found that chronic exposure to wood smoke increases MCV.
This might be due to differences in the type of wood used as a fuel leading to microcytic
anemia.
d. Mean corpuscular hemoglobin (MCH)
The blood samples were also analyzed for mean corpuscular hemoglobin and the
results has been given in Table 4. The mean and standard deviation of MCH in workers
1516
was 28 ± 1.2 pg with a range of 26 to 30 pg. For control the value was 33 ± 3.7 pg with a
range of 30 to 39 pg. The result showed significant (P<0.05) decrease in MCH of workers
as compared to control. Unlike our study the results of Kondo et al., 1993 and Nabi et
al., 2014 are not in agreement which might be due to differences in the type of wood
used for fuel.
e. Mean corpuscular haemoglobin concentration (MCHC)
The mean along with standard deviation of MCHC in workers was 29 ± 2.9 % having a
range of 25 to 32 % and in control was 33 ± 1.5 % with a range of 30 to 34 %. The values
for both groups have given in Table 4. The result showed that there is a significant
(P<0.05) decreased in the MCHC of workers as compared to control. The present study
showed deviation from the result of Kondo et al., 1993 and Nabi et al., 2014 who
reported that individual chronically exposed to smoke has higher level of MCHC. This
differences might be due to differences in type of fuel used.
f. Total leukocyte count (TLC)
The TLC of both the workers and control are given in Table 4. The mean along with
standard deviation of brick making workers was 7097± 1004/cmm with a range of 5700
to 8300 /cmm. The total leucocytes count of control was 7287 ± 762 /cmm with a range of
6633 to 8600 /cmm. The results showed that in workers TLC was significantly (P<0.05)
lowered as compared to control group. Our findings are not parallel with the results of
Kondo et al., 1993; Megan and Smith, 2003; Yanbaeva et al., 2007 and Nabi et al., 2014
who reported high TLC level in people exposed to chronic smoke. This low TLC might
be due to shift of acute body response to chronic response.
g. Neutrophil count
The mean along with standard deviation of neutrophils in control was 47.54 ± 2.6 % and
its range was 42-51 %, and that of workers was 65.2 ±4.3 % with a range of 61-72 %. The
result showed a significant (P<0.05) increase in the neutrophils concentration of brick
making workers than that of control. The result of Schwartz, 2001; Perez et al., 2010 and
Nabi et al., 2014 are an agreement with our study who reported high percentage of
neutrophil count in people exposed to chronic smoke.
h. Lymphocytes count
The mean ± standard deviation of lymphocyte count in workers was 50 ± 4.2 % with a
range of 42 to 56 % and that in control was 27 ± 3.8 % with a range of 21 to 31%. The
results showed that there was a significant increase (P<0.05) in the lymphocytes count of
workers compared to control (Table 4). Our findings are parallel with the results of
1517
Rutgerz et al., 2000 and Nabi et al., 2014 who reported significantly increased
lymphocyte count in people chronically exposed to smoke as compared to control
group.
i. Platelets count
The mean ± standard deviation of platelets count in both the brick making workers and
control has been given in Table 4. In workers the mean and standard deviation of
platelets was 245600 ± 41500 /cmm with a range of 173000 to 341000 /cmm and in
control it was 268200±49114 /cmm with a range of 225000 to 380000 /cmm. There was a
significant (P<0.05) decreased in the platelets count of workers when compared with
control group. The analyzed result of Ray et al., 2006 and Nabi et al., 2014 deviate from
the present study who documented that chronic biomass smoke exposure activates
circulating platelets.
CONCLUSION AND RECOMMENDATION
The present study was analyzed to investigate the ill effects on health status of brick
kiln workers who are occupationally exposed to heat and smoke. Brick kiln smoke is a
worldwide problem as it emits the toxic fumes like Nox and Sox. These gases are
threaten to health. The workers are regularly exposed to the brick kiln smoke and heat
leading to acute and chronic pulmonary diseases, lung infection, chest pain, allergy, dry
cough and physical weakness. The blood biochemical parameter such as, SGPT,
glucose, cholesterol, and triglyceride levels of brick kiln occupants were found higher as
compared to control group. The printed as well as electronic media should aware the
people from the hazardous effects of smoke and dust generation during cooking of
bricks. The Environmental Protection Agencies (EPA) should emphasized on burning
devices to regulate its manufacturing and to avoid the emission of huge amount of
smoke. Seminars should be arranged in educational institutions. Labors should get
social security, healthcare and education facilities.
1518
Table 1: History of workers (n=10)
Age group
No. of
Marital
Exposure
Total time
Health
(years)
workers
Status
time
(years)
problems
problems
before
after the job
(hours/day)
Health
the
job
18-24
2
Unmarried
12
3
No specific
No specific
25-31
2
Married
12
5
No specific
Appendicitis
32-38
4
Married
12
20
No specific
Allergy
39-45
1
Married
12
35
No specific
Joint
pain,
Physical
weakness
46-52
1
Married
12
30
No specific
lung
infection,
Hip pain
Table 2: History of control (n=5)
Age (years)
No of control
Marital status
Exposure time
Health problems
20
1
Unmarried
No exposure
No specific
29
1
Married
No exposure
No specific
40
1
Married
No exposure
No specific
42
1
Married
No exposure
No specific
51
1
Married
No exposure
No specific
Table 3: Blood biochemical parameters of both brick making workers and control
Parameters
Workers (n =10)
Control (n = 5)
Mean ± SD*
Mean ± SD*
Cholesterol (mg/dl)
204 ± 6.2
166 ± 16
Glucose (mg/dl)
176 ± 1.8
79 ± 18
Triglyceride (mg/dl)
203 ± 4.9
143 ± 22
SGPT* (IU/L)
53 ± 1.7
23 ± 6.7
SD*=Standard Deviation, SGPT*= Serum Glutamate Pyruvate Transaminase
Table 4: Complete blood profile of brick making workers and control
Parameters
Workers (n=10)
Control (n=5)
Mean ± SD*
Mean ± SD*
Hb* (gm/dl)
13 ± 1.5
13 ± 1.6
Total RBC* (mil/cmm)
3.7 ± 0.56
4.0 ±0.36
HCT* (%)
36 ± 2.9
43 ±1.7
1519
MCV*(fl)
81 ± 3.6
97 ± 4.7
MCH* (pg)
28 ± 1.2
33 ± 3.7
MCHC* (%)
29 ± 2.5
33 ± 1.5
TLC* (/cmm)
7097 ± 1004
7287 ± 762
Neutrophils (%)
65.2±4.3
47.5±2.6
Lymphocytes (%)
50 ± 4.2
27 ± 3.8
Platelets (/cmm)
245600±41500
268200±49114
SD*= Standard Deviation, RBC* = Red Blood Cells, Hb* = Hemoglobin, MCV* = Mean Cell Volume,
MCH* = Mean Corpuscular Hemoglobin, HCT *= Hematocrit, TLC*= Total Leukocyte Count, MCHC*=
Mean Cell Hemoglobin Concentration
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