ASSESSMENT OF SOME HAEMATOLOGIC PARAMETERS AMONG TRICYCLE DRIVERS IN ABA, ABIA STATE, NIGERIA
Abstract
ASSESSMENT OF SOME HAEMATOLOGIC PARAMETERS AMONG
TRICYCLE DRIVERS IN ABA, ABIA STATE, NIGERIA
BY
EMEZUE, PRECIOUS CHINECHEREM
2018/116132/REGULAR
PROJECT SUBMITTED TO
DEPARTMENT OF HAEMATOLOGY AND BLOOD TRANSFUSION
SCIENCE
FACULTY OF MEDICAL LABORATORY SCIENCE, COLLEGE OF
MEDICINE AND HEALTH SCIENCES
ABIA STATE UNIVERSITY, UTURU
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE
AWARD OF BACHELOR OF MEDICAL LABORATORY SCIENCE
(B.MLS) DEGREE OF ABIA STATE UNIVERSITY, UTURU
SUPERVISOR:
DR. OKEZIE CALEB OKAMGBAI
JULY, 2024.
DECLARATION
I, EMEZUE, PRECIOUS CHINECHEREM with matriculation number
2018/116132/REGULAR hereby declare on my honor, that this research study
has not been previously presented either wholly or in parts for the award of any
other Degree, Diploma certificate or publication in any university or higher
institutions elsewhere.
…………………………...................
…………………
EMEZUE, PRECIOUS CHINECHEREM DATE
2018/116132/REGULAR
CERTIFICATION
This is to certify that I, EMEZUE, PRECIOUS CHINECHEREM with the
Matriculation number 2018/116132/REGULAR from the department of
Haematology and Blood Transfusion Sciences, Faculty of Medical Laboratory
Science, College of Medicine and Health Science Abia State University, Uturu,
carried out this project “Assessment of Some Haematologic Parameters Among Tricycle
Drivers in Aba, Abia State, Nigeria” under the supervision of DR. OKEZIE
CALEB OKAMGBA
….………………………. ……………………….
DR. OKEZIE CALEB OKAMGBA Date
(Supervisor)
…………………………
…………………………
Dr. OKEZIE CALEB OKAMGBA Date
(Dean Faculty of Medical Laboratory science)
….………………………. …….……………………
(External Examiner) Date
DEDICATION
This research work is dedicated to God Almighty.
ACKNOWLEDGEMENT
First of all, I give thanks to God Almighty for giving me an opportunity to
excel in my effort to complete this project on time.
I am very much thankful to my project supervisor who doubles as the dean
faculty of Medical Laboratoratory Sciences, Abia State University, Uturu, DR.
OKEZIE CALEB OKAMGBA, for his valuable guidance, keen interest,
encouragement and constructive criticism at various stages of this research
work.
I appreciate all the lecturers of the department of Medical Laboratory Science,
Abia State University Uturu who contributed to my academic growth
I am extremely grateful to my parents……, for their unending love, moral,
financial and all-round support.
Finally, I will be failing in duty if I do not acknowledge with grateful thanks,
the authors of the references and other literatures referred to in this research.
TABLE OF CONTENTS
Cover page
Title page
i
Declaration
ii
Certification iii
Dedication
iv
Acknowledgement v
Table of
Contents vi
List of Tables
viii
List of Figures
ix
Abbreviations x
Abstract
xi
CHAPTER ONE: INTRODUCTION
1.1
Background 1
1.2 Statement of
Problem 4
1.3 Justification of
Study 4
1.4 Aim of
Study 5
1.5 Specific
Objectives
5
CHAPTER TWO: LITERATURE REVIEW
2.1 Occupational
Hazards 6
2.1.1 Prolonged
Siting 6
2.1.2 Environmental
Pollutants 7
2.2 Occupational Disorders in Transport
Drivers 8
2.2.1 Cardiovascular System
Disorders 8
2.2.2 Musculoskeletal
Disorders 10
2.3 Haematologic Changes Associated with Tricycle
Driving 12
2.3.1 Effect of Exposure to Volatile Organic
Compounds 12
2.3.2 Effects of
Stress 16
2.4 Laboratory Diagnostic
Methods 17
CHAPTER THREE: MATERIALS AND METHODS
3.1 Study
Area 22
3.2 Study
Design 22
3.3 Sample
Size 22
3.4 Sampling
Technique 23
3.5 Inclusion
Criteria 23
3.6 Exclusion
Criteria 23
3.7 Ethical
Approval 23
3.8 Sample Collection and Preparation
24
3.9 Laboratory
Methods 24
3.10 Statistical
Analysis 25
CHAPTER FOUR
Result and Analysis
26
CHAPTER FIVE: DISCUSSION
5.1
Discussion 34
5.2
Conclusion 36
5.3
Recommendations 36
References
37
Appendix 42
LIST OF TABLES
4.1 Comparison of Mean±SD ofHB, PCV, RBC, PLT, TWBC, NEUT,
LYM, MON, BAS, EOS, MCV, MCH, MCHC of Tricycle Drivers and
Healthy Non-Tricycle Drivers Using Student T-
Test. 27
4.2 Comparison of Mean±SD ofHB, PCV, RBC, PLT, TWBC, NEUT,
LYM, MON, BAS, EOS, MCV, MCH, MCHC of Tricycle Drivers Based
on Age, Using ANOVA and Post
HOC. 29
4.3 Comparison of Mean±SDofofHB, PCV, RBC, PLT, TWBC, NEUT,
LYM, MON, BAS, EOS, MCV, MCH, MCHC of Tricycle Drivers Based
on Duration of Use, Using Student’s T-
Test. 33
ABBREVIATIONS
PMS- Premium Motor Spirit
MetHb- Methaemoglobin
VOCs- Volatile Organic Compunds
CBC- Complete Blood Count
PM- Particulate Matter
CO- Carbon Monoxide
NO2- Nitrogen Dioxide
SHR- Standardized Hospitalization Ratio
WBV- Whole Body Vibrations
CFC- Colony Forming Cells
HPAA- Hypothalamus–Pituitary–Adrenal Axis
ROS- Reactive Oxygen Species
WHO- World Health Organization
ABSTRACT
The nature of work and lifestyle of commercial cyclists predisposes them to
various conditions that can lead to anemia. This condition, characterized by a
deficiency in red blood cells or hemoglobin, adversely affects hematopoiesis
and increases the risk of morbidity and mortality. Factors such as prolonged
physical exertion, inadequate nutritional intake, and exposure to environmental
pollutants further exacerbate their susceptibility. This study determined some
haematological parameters among tricycle drivers. A total of 100 subjects; 50
tricycle drivers and 50 non-tricycle drivers, were recruited for the study. Ethical
approval for the study was obtained from the ethics committee of the Faculty of
Medical Laboratory Science Uturu, Abia State. Parameters studied were HB,
PCV, RBC, PLT, TWBC, NEUT, LYM, MON, BAS, EOS, MCV, MCH, and
MCHC. Parameters were determined using automated haematologyanalyser
model and data generated wasanalysed statistically using Student's t-test. The
mean±SD for HB, PCV, RBC, PLT (12.14±1.606g/dl, 0.38±4.292L/L,
4.31±0.262x1012/L, 177.13±46.286x109/L, respectively) of tricycle drivers were
lower and statistically significant (p≤0.05) when compared with values of non-
tricycle drivers (13.90±1.042g/dl, 0.42±3.723L/L, 6.12±0.832x1012/L,
268.94±39.971x109/L, respectively). Findings of this study showed that tricycle
driving interferes with the haematological system.
CHAPTER ONE
INTRODUCTION
1.1 Background
Transportation of persons, goods and services are inevitable necessities in every
society. In developing countries like Nigeria, commercial transportation is a key
element of economic growth (Atubi, 2015). For commercial purposes, the
commonest means of transportation in developing countries like Nigeria are
buses, taxi cabs, motorcycles and tricycles. The task of tricycling involves
riding a three-wheeled vehicle (tricycle) which is also referred to as a
kekenapep (Nigeria), three-wheeler, tuk-tuk, trishaw, autorick or bajaj (in
Indonesia) and auto rickshaw (in India) (Ojukwuet al., 2020). Recently,
tricycling is rapidly becoming more popular as a means of commercial transport
in several developing countries, particularly in Asian and African countries
(Grieshop et al., 2012). Tricycles exist in several types and designs. The
commonest type is characterized by a sheet-metal body or open frame resting on
three wheels, canvas roof with drop-down side curtains, small cabin at the front
for the driver with handlebar controls, and a cargo, passenger, or dual purpose
space at the bar (Ojukwuet al., 2020). Owing to the heavily congested nature of
Nigerian roads, the small size and narrow configuration of tricycles are
perfectly suited to navigate the roads. However, there are some possible health
risks associated with commercial tricycling, relative to the configuration of
tricycles and the environmental exposure of tricyclists to airborne pollutants.
Studies have shown that inhalation of petroleum products are associated with
reduced haematological indices which worsens with prolonged exposure
(Olayanjuet al., 2021). This is seen among tricycle drivers due to frequent visits
to fuel stations and to mechanic workshops. Crude oils and other refined oil
products are both used in petrol (premium motor spirit (PMS). In terms of
polycyclic aromatic hydrocarbons, it is a substantial source (Getuet al., 2020).
Crude oil is delivered to an oil refinery after extraction, where complex
hydrocarbon compounds are separated and processed into fuel-useable forms
using various refining procedures. The presence, physico-chemical properties
and toxicological characteristics of other important petroleum products like
benzene, toluene, xylenes, ethyl-benzene, n-hexane, volatile hydrocarbons
belonging to gasoline, kerosene, and diesel fuel (contents defined by the
technology of the manufacturing processes), determine the extent of impacts of
this industry on both the workers and environment (Ezejiofor, 2016). Benzene is
one of the natural constituent of crude oil as well as a product of petrol refining.
Benzene is one of the main carcinogens among more than 165 occupational
carcinogens which are identified by the International Agency for Research on
Cancer (IARC) (Ekpenyong and Asuquo, 2017). Few studies have reported
haematological disorders associated with the exposure tobenzene in the
environment in less developed countries (Ng and Newson-Smith, 2022; Sahb,
2011). However, there is evidence linking PMS and low dose exposures to
volatile organic compounds, such as benzene, to adverse health effects
(Udonwaet al., 2019). It is extremely hazardous when inhaled and can cause
neurological problems, irritation of the mucous membranes, and other
symptoms related to respiratory failure. Chronic exposure has been linked to
heart attacks, cardiac irregularities, bone marrow depression, leukemia,
stomach, lungs, and brain malignancies, among other conditions (Curtis et al.,
2022; Udonwaet al., 2019). Following inhalation, benzene vapour is rapidly
absorbed into the blood and distributed throughout the body (Cooper and
Snyder, 2017). One of the effects of benzene in the body is the production of
methaemoglobin (MetHb) which differs from haemoglobin. Haemoglobin
accepts and transports oxygen only when the iron atom isin its ferrous form.
When haemoglobin becomes oxidized, iron is converted to the ferric state (Fe3+)
or MetHb. MetHb lacks the electron that is needed to form a bond with oxygen
and, thus, is incapable of oxygen transport. Since red blood cells are
continuously exposed to various oxidant stresses, blood normally contains
MetHb levels of between 1and 3% (Udonwaet al., 2019). Considering that
MetHb has little affinity for oxygen, transport of the later to cells is hindered
resulting in functional anaemia. As the level of MetHb increases, symptoms like
shortness of breath, palpitation, anxiety and confusion occur. Humans are
commonly exposed to benzene and other VOCs through the pulmonary and
dermal pathways (Pal et al., 2022).
Studies have also shown that haemorrhoids are associated with tricyclists due to
prolonged sitting (Valachi and Valachi, 2013; Olayanjuet al., 2021).
Haemorrhoids cause gastrointestinal bleeding, which is an established cause of
iron deficiency anaemia. Iron deficiency is one of the common nutritional
deficiencies worldwide. The nature of work and lifestyle of commercial
tricyclists predisposes them to various conditions that can lead to anaemia,
which in turn affect haematopoiesis and cause morbidity and mortality.
A complete blood count (CBC) is a test that provides information about the
distribution and quantity of blood cells. This test provides valuable information
about the kinds and the numbers of cells in the blood particularly red blood cells
(RBC), white blood cells (WBC), and platelets that indicates health
professionals to check symptoms, like weakness, fatigue, or bruising. In
addition, it also diagnoses pathologic conditions such as anemia. It can reflect
acute or chronic infection allergies and problems with clotting. So, CBC is an
easy and readily available screening tool for evaluating hematotoxicity of
benzene (Getuet al., 2020).
1.2 Statement of Problem
Commercial tricyclists, due to the physical demands and lifestyle associated
with their occupation, are particularly susceptible to developing conditions that
can lead to anaemia. This vulnerability is exacerbated by factors such as
prolonged periods of physical exertion, inadequate nutritional intake, and
exposure to environmental pollutants. Anaemia, characterized by a deficiency in
the number or quality of red blood cells, can severely impact hematopoiesis and
lead to various health complications, including increased morbidity and
mortality. Despite the critical role of commercial tricyclists in urban
transportation systems, there is a paucity of research focusing on their
haematologic health. This study aims to bridge this gap by investigating the
changes in key haematologic parameters such as hemoglobin concentration
among commercial tricyclists and propose potential interventions to improve
their haematologic health.
1.3 Justification of Study
Studies have shown that inhalation of petroleum products are associated with
reduced haematological indices which worsens with prolonged exposure
(Olayanjuet al., 2021). Studies have also shown that haemorrhoids are
associated with tricyclists due to prolonged sitting (Valachi and Valachi, 2013;
Olayanjuet al., 2021). Although a few studies have studied the implications of
tricycle driving on haematologic parameters, no such study has been carried out
in the present study area. This study was to assess some haematologic
parameters in tricycle drivers, with a view to determining haematologic test(s)
that could predict haematologic abnormalities early and thus allowing for
prompt treatment.
1.4 Aim of Study
To determine some haematologic parameters in tricycle drivers.
1.5 Specific Objectives
1. To assess HB, PCV, RBC, PLT, total WBC, differential WBC, MCV, and
MCH, MCHC among tricycle drivers and non-tricycle drivers.
2. To investigate the effect of age on HB, PCV, RBC, PLT, total WBC,
differential WBC, MCV, and MCH, MCHC among tricycle drivers.
3. To ascertain the duration of driving on HB, PCV, RBC, PLT, total WBC,
differential WBC, MCV, and MCH, MCHC among tricycle drivers.
CHAPTER TWO
LITERATURE REVIEW
2.1 Occupational Hazards
2.1.1 Prolonged Sitting
Some occupations such as office work and driving are associated with prevalent
occupational hazardsand these have adverse health implications. Individuals
engaged in such occupations require prolonged sitting and often, they
experience a myriad of physiological and metabolic changes that may
detrimentally and impact their health.
Prolonged sitting has been consistently linked to an increased risk of
cardiovascular diseases, including hypertension, coronary artery disease, and
stroke. Sedentary behavior leads to reduced blood flow, endothelial dysfunction,
and impaired vasodilation, predisposing individuals to atherosclerosis and
cardiovascular events. Additionally, prolonged sitting promotes the
accumulation of visceral adipose tissue, dyslipidemia, and insulin resistance,
contributing to metabolic syndrome and cardiovascular risk factors. Sitting for
prolonged periods leads to decreased muscle contraction and venous return,
predisposing individuals to venous stasis and thrombotic events. Reduced lower
limb blood flow, increased capillary permeability, and endothelial dysfunction
contribute to venous thromboembolism and deep vein thrombosis. Moreover,
prolonged sitting impairs arterial stiffness, augments sympathetic nervous
system activity, and elevates blood pressure, further exacerbating cardiovascular
risk (Ronchese and Bovenzi, 2012).
Sitting for prolonged periods can exert excessive pressure on the
musculoskeletal system, leading to musculoskeletal disorders such as low back
pain, neck pain, and joint stiffness. Reduced muscle activation and prolonged
static postures contribute to muscle imbalances, decreased flexibility, and spinal
degeneration. Moreover, poor ergonomic design of workstations and seating
arrangements may exacerbate musculoskeletal strain and increase the risk of
occupational injuries. Sedentary behavior is associated with metabolic
dysfunction, characterized by dysregulated glucose metabolism, insulin
resistance, and impaired lipid metabolism. Prolonged sitting suppresses skeletal
muscle glucose uptake, reduces lipoprotein lipase activity, and promotes
adipocyte hypertrophy, contributing to obesity and metabolic syndrome.
Furthermore, sedentary behavior disrupts circadian rhythms, alters appetite
regulation, and promotes excessive calorie intake, exacerbating metabolic
dysfunction and weight gain (Ronchese and Bovenzi, 2012).
2.1.2 Environmental Pollutants
Tricycle driving, a common occupation in many urban and peri-urban areas,
exposes drivers to a variety of environmental pollutants that pose significant
occupational health hazards (Marijaet al., 2022). Tricycle drivers, often
navigating through congested traffic and busy streets, encounter elevated levels
of air pollutants, including particulate matter, carbon monoxide, nitrogen
dioxide, and volatile organic compounds (Marijaet al., 2022). Urban
environments are characterized by high levels of air pollution resulting from
vehicular emissions, industrial activities, and combustion processes. Tricycle
drivers, operating in densely populated urban areas with heavy traffic
congestion, are particularly susceptible to inhalation exposure to airborne
pollutants emitted by motor vehicles and surrounding sources (Marijaet al.,
2022).
Tricycle drivers are exposed to a diverse array of environmental pollutants,
including:
Particulate Matter (PM): Fine particulate matter, PM2.5, and coarse particulate
matter, PM10, are inhalable pollutants generated by vehicle exhaust, road dust,
and industrial emissions. PM exposure has been linked to respiratory irritation,
lung inflammation, and cardiovascular morbidity (Alemayehuet al., 2020).
Carbon Monoxide (CO): Produced by incomplete combustion of fossil fuels,
CO is a colorless, odorless gas that binds to hemoglobin, impairing oxygen
delivery to tissues and organs. Chronic CO exposure can lead to headaches,
dizziness, and cardiovascular complications (Marijaet al., 2022).
Nitrogen Dioxide (NO2): A common air pollutant generated by motor vehicle
emissions and combustion processes, NO2 contributes to respiratory symptoms,
airway inflammation, and asthma exacerbations (Marijaet al., 2022).
Volatile Organic Compounds (VOCs): Organic chemicals released from vehicle
exhaust, fuel combustion, and industrial activities, VOCs contribute to ground-
level ozone formation, smog, and respiratory irritation (Marijaet al., 2022).
2.2 Occupational Disorders in Transport Drivers
2.2.1 Cardiovascular System Disorders
Transportation workers have an increased occurrence of cardiovascular
pathologies, including myocardial infarction and other manifestations of
coronary artery disease, in association with arterial hypertension and
cerebrovascular pathologies (stroke) (Ronchese and Bovenzi, 2012). The
etiopathogenetic mechanisms associated with the excess of cardiovascular
diseases in transportation workers are multifactorial in nature, and the relative
importance of various occupational risk factors and their interaction with extra-
professional ones are not well defined (Ronchese and Bovenzi, 2012).
Several studies conducted between the late 1980s and the early 1990s
highlighted an excess risk for cardiovascular diseases among professional
drivers.
In a Danish study analyzing causes of hospitalizations and hospital deaths due
to ischemic heart disease between 1981 and 1985, male urban and intercity bus
drivers showed a high standardized hospitalization ratio for ischemic heart
disease compared to the general population (standardized hospitalization ratio,
SHR 136). The excess hospitalization was particularly evident for urban bus
drivers (SHR 143) and male taxi drivers (SHR 168) (Ronchese and Bovenzi,
2012).
In a study on the incidence of myocardial infarction among bus drivers in
Sweden, a cohort of 9446 male drivers exhibited a 50% excess in mortality due
to myocardial infarction compared to a control group recruited from other
sectors over a 15-year period. Urban bus drivers had a relative risk (RR) of 1.6
(95% CI 1.1-1.9) for the first episode of myocardial infarction. Among the
occupational risk factors, authors suggested the possible role of work-related
stress, shift work patterns, sedentary work, vehicle exhaust fumes, and noise
(Ronchese and Bovenzi, 2012).
Analyzing the causes of increased ischemic heart disease risk in urban bus
drivers, authors suggested the possible contribution of psychosocial stress
factors, particularly high job demands associated with low job control,
conditions reported by over 80% of the subjects surveyed (Ronchese and
Bovenzi, 2012).
2.2.2 Musculoskeletal Disorders
The relationship between driving activities and musculoskeletal disorders has
long been documented. Several clinical-epidemiological studies have found an
excess occurrence of disorders/pathologies of the cervical and lumbar spine in
professional drivers compared to control groups or the general population. One
limitation of these studies is that they are predominantly cross-sectional
investigations, while studies with a longitudinal design are scarce (Ronchese
and Bovenzi, 2012).
Investigations in recent years tend to confirm an increased risk for low back
pain in professional drivers. In 2005, Hoy et al. investigating a population of
forklift drivers, reported a prevalence of low back pain almost double that of the
control group (65% vs. 34.8%), corresponding to an OR of 3.5 (95% CI 1.04–
11.8). The intensity of low back pain was also significantly higher in forklift
drivers compared to controls (44% vs. 22%). Among truck drivers,
Andrusaitiset al. (2012) found a prevalence of low back pain of 59%, a figure
comparable to that reported by Okunribidoet al. (2011) within a cohort of bus
drivers (59%). The prevalence of low back symptoms was associated with
driving duration expressed in hours (OR 1.07; 95% CI 1.01-1.13), confirming
what has already been reported in other studies in the literature on a cohort of
urban taxi drivers.
Increased prevalences of musculoskeletal disorders in the upper and lower limbs
have been associated with driving activity: the most frequently reported
disorders were localized at the hip-thigh (22.2%) and knees (29.3%) for the
lower limbs, and at the elbow (10.8%) and arms (17.5%) for the upper limbs.
Most drivers who complained of these disorders associated them with driving
conditions and the ergonomic characteristics of the workstation. Ergonomic
factors associated with the onset of musculoskeletal disorders, both at the
lumbar level and at the upper limb level, were uncomfortable seats (OR 2.2;
95% CI 1.2-4.3), inadequate lumbar support (OR 2.3; 95% CI 1.2-4.2) and
steering wheel characteristics (OR 2.2; 95% CI 1.1-4.5). Another relevant factor
was the frequent flexion/torsion movements during driving activity (OR 1.86;
95% CI 1.15–2.99) (Ronchese and Bovenzi, 2012).
Numerous epidemiological studies have shown that the excess risk for low back
pain and other musculoskeletal disorders (cervical pain, brachialgia, and knee
pain) in professional drivers is associated with driving seniority, magnitude, and
duration of exposure to whole-body vibrations (WBV), as well as, as mentioned
above, assuming incongruous postures. A meta-analysis of epidemiological
studies on musculoskeletal pathologies in professional drivers has shown
significant associations between exposure to WBV and the onset of low back
pain, sciatica, and early degeneration, not related to age, of the spine. Some
studies have also reported an excess prevalence of spondylolisthesis and higher
rates of hospitalization for cervical and lumbar discopathy in professional
drivers compared to the general population. These conditions were significantly
associated with driving seniority (OR 3.4; 95% CI 1.1 - 10.7, for work seniority
> 15 years vs< 5 years) (Ronchese and Bovenzi, 2012).
Like vascular pathologies, musculoskeletal pathologies, especially those
affecting the spine, have a multifactorial origin. In addition to exposure to WBV
and unfavorable ergonomic factors, the contribution of work-related stress and
adverse psychosocial factors has been reported. It has been observed that the
occurrence of disorders/pathologies of the lumbar spine is associated with heavy
traffic conditions (OR 1.8; 95% CI 1.2–2.7) and with a limitation of leisure time
beyond working hours (OR 1.6; 95% CI 1.0–2.6). The role of psychosocial
factors in the workplace, such as "job demand-control," "job support," and "job
satisfaction" in Anglo-Saxon terminology, is still a matter of debate as various
epidemiological studies and meta-analyses of literature data offer a non-
univocal interpretation of their contribution to the etiopathogenesis of
musculoskeletal disorders/pathologies in professional drivers (Ronchese and
Bovenzi, 2012).
2.3 Haematologic Changes Associated with Tricycle Driving
2.3.1 Effect of Exposure to Volatile Organic Compounds
Benzene
Benzene (C6H6) is the parent hydrocarbon of the aromatic group, the resonant
cyclic compound consisting of only carbon and hydrogen (Aksoy, 2017).
Benzene can be found in products such as gasoline, nail polish, acrylic spray
paint, airplane glue, cleaning products, and paint thinners. Benzene exposure,
whether environmental, accidental or intentional, can cause toxicity throughout
the body, specifically affecting the pulmonary system, central and peripheral
nervous system, gastrointestinal, cardiovascular, renal, hepatic, and
haematological systems (Ekpenyong and Asuquo, 2017).
Acute benzene toxicity usually occurs following inhalation of concentrated
benzene vapour, usually in poorly ventilated rooms. The clinical findings, the
severity of symptoms and outcome of acute benzene toxicity depend on the
amount of toxic vapour inhaled and the duration of the exposure (Aksoy, 2017).
Benzene is absorbed through the lungs and approximately 40 or 50 percent of it
is retained. Due to the high lipid solubility, benzene accumulates in fat and
nervous system and about 40-50 percent of benzene with some carbon dioxide
is excreted unchanged from the lungs and a small percentage of benzene is
exhaled unchanged even after 24 hours. As it is known the major organ system
implicated for benzene metabolism are the liver and the bone marrow. After
inhalation, apart from insignificant traces of benzene in urine, most of the
absorbed benzene remaining is ultimately metabolized into derivatives which
are more water soluble and thus more removable by the kidneys. The fact that
the benzene metabolizing system is located in the cell microsomal fraction of
the liver is demonstrated by differential centrifugation of the liver homogenate.
The mixed function oxidases (mono-oxidases) in the endoplasmotic reticulum
of the parenchym cells perform epoxidation of the nucleus to form arene oxides
which decompose spontaneously to form phenol. Benzene oxide or epoxide, an
unstable chemical which can attach to DNA or RNA giving cause to mutation.
Furthermore, recently some studies found out experimentally that high doses of
benzene such as 4680 or 4000 ppm cause rapid decrease of colony forming cells
(CFC). This disclosed that benzene inhibits the self renewal of pluripotent stem
cells and that of the cells of microenvironment and by this phenomenon causes
aplastic anaemia (Aksoy, 2017). Benzene is a suspected Leukemogenic agent
and intake of high doses of benzene causes malignant tumours in several
tissues. If an agent is toxic to the pluripotent stem cell or to microenvironment,
it can cause an alteration in the two important capabilities of the colony forming
cells namely; Self renewal and Differentiation to produce a variety of lineage
progenitor cells. Any block or disturbance in these capabilities will cause either
aplastic anaemia (a block in self renewal) or leukemia (a block in
differentiation).
Benzene is known to cause haematological disorders. Rarely, can result in
death. Benzene being one of the main constituent of most spray paints is a
major cause of hazards associated with spray painter’s job (Ekpenyong and
Asuquo, 2017). Solvents, after being absorbed into the intercellular fluid, may
enter main bloodstream and get distributed throughout the body (Baynes
and Hodgson, 2004). Blood production is affected by benzene, because the bone
marrow is affected. There is an excessive risk of haematopoietic diseases
because of relatively high past exposure to benzene has been reported in Korean
industries Thus, occupational exposure to benzene leads to haematotoxicity and
other blood disorders such as blood cancer (leukaemia), aplastic anaemia, and
dysplastic bone marrow conditions are the most common results of exposure to
aromatics such as benzene (Ekpenyong and Asuquo, 2017). .
The effects of benzene include leukocytopenia, thrombocytopenia, anaemia,
transitory leukocytosis, lymphopenia, rarely lymphocytosis. Human exposure
to benzene in working environment is a global occupational health problem. It
has been established that benzene requires to be metabolized to induce its
effects. Benzene has been associated with various haematotoxins and
carcinogens. Benzene, also known as benzol, is a volatile, colorless,
highly flammable liquid, with a characteristic sickly sweet odor and was
discovered in 1825 by Faradat who isolated it from a liquid condensed by
compressing oil gas (Ekpenyong and Asuquo, 2017).
Lead
Lead is a pigment in petrol. Lead (Pb) is one of the most widely scattered toxic
metals in the world. An overview of lead exposure can be obtained from a
number of tissues and fluids in human body, such as blood, hair, bone, and
urine.
Generally, it is known that lead exposure could have health risks, such as
damage to central nervous and peripheral nerves, cardiovascular system,
haematopoietic system, kidneys, digestive system and reproductive system
(Shukla et al., 2018). It is also stated as carcinogenic element. Lead interferes
with heme biosynthesis by altering the activity of three enzymes namely;
aminolevulinic acid synthetase (ALAS), aminolevulinic acid dehydratase
(ALAD) and ferrochelatase. Lead indirectly stimulates the mitochondrial
enzyme ALAS, which catalyzes the condensation of glycine and succinyl Co-A
to form aminolevulinic acid or ALA. Lead also inhibits the zinc containing
cytosolic enzyme ALAD, which catalyzes the condensation of two units of ALA
to form porphobilinogen. This inhibition is non competitive and occurs through
the binding of lead to vicinal sulfhydryls at the active sites of ALAD. Lead
bridges the vicinal sulfhydryls. The end results of these changes in enzyme
activities are Coproporphyrin, d-aminolevulinic acid (ALA), increased urinary
porphyrins and increased erythrocyte protoporphyrin (Patilet al., 2017). Lead
has been known to alter the haematological system. The anaemia induced by
lead is microcytic and hypochromic and results primarily from both inhibition
of heme and globin synthesis and shortening serum level of erythropoietin; a
hormone that regulates erythrocyte formation which might also affect the
reserve capacity for erythropoiesis. Lead causes oxidative stress by inducing the
generation of reactive oxygen species (ROS), reducing the antioxidant defence
system of cells through depleting glutathione, interfering with some essential
metals, inhibiting sulfhydryls, dependent enzymes or antioxidant enzymes
activities and/or increasing susceptibility of cells to oxidative attack by altering
membrane integrity and fatty acid composition.
Research of lead exposure in haematology is very important because the
erythrocytes in bone marrow and blood is the main lead toxicity target in adults.
Lead can cause erythrocytes haemolysis and inhibit the formation of
haemoglobin (van-Avondtet al., 2019). Patrick (2016) stated that lead can
cause G-6PD enzyme deficiency pyrimidine-5’- nucleotidase enzyme
inhibition in mature erythrocytes. This leads to the decline of the erythrocytes
lifespan and increase the vulnerability of erythrocytes membrane, thus reduce
the number of erythrocytes. Enzyme deficiency is characterized by the
presence of basophilic stripling of erythrocytes. Lead could inhibit haem
biosynthesis through the inhibition of δ-ALAD, coproporphyrinogen, and
ferrochelatase enzyme, thus cause the reduction of haemoglobin concentration
in blood.
Anaemia may develop with lead poisoning due to impaired synthesis of haem,
haemolysis of red cells and shortened red cell survival. Anaemia is usually mild
and is more commonly seen in adults. Lead inhibits the body's ability to make
haemoglobin by interfering with several enzymatic steps in the haem
synthesis pathway (Ray, 2016).
2.3.2 Effects of Stress
Stress, defined as the physiological response to adverse stimuli, encompasses a
multitude of psychological, environmental, and physiological factors. The
impact of stress on various bodily systems has been extensively studied, yet its
intricate relationship with the haematologic system remains a subject of ongoing
research and interest. Stress can lead to many health disorders via many of the
behavioral and physiological pathways due to some essential biochemical,
metabolic, and hormonal pathways (Al-Hatamlehet al., 2020). The dramatic
elevation of the chemical mediators which have been release by body during
stressful event produced many physiological effects (Al-Hatamlehet al., 2020).
To add on, stress reaction will lead to neuroendocrine response which involved
the sympathetic nervous system, and the hypothalamus–pituitary–adrenal axis
(HPAA) stimulation that will result in the secretion of glucocorticoids and
catecholamine. Subsequently, this response will be followed by a sharp increase
in oxidative stress (Al-Hatamlehet al., 2020).
Oxidative stress describes the imbalance status between free radicals and
antioxidants in the body, which resulting in the damage of important
biomolecules and cells that consequently will give impact on the whole body
(Al-Hatamlehet al., 2020). Meanwhile, free radicals are unstable molecules, or
atoms having an unpaired valence electron that are eligible to stay in
independent existence status. These free radicals may cause damage of fatty
acids and proteins in the cell membrane, which lead to the destruction of cells
due to its characteristics of having an odd number of electrons, thus make it
short-lived and highly reactive. Noteworthily, reactive oxygen species (ROS)
are classified as the most common and harmful types of free radicals (Al-
Hatamlehet al., 2020).
In addition to the well-established mechanisms of initial coordination of pro-
inflammatory cytokine production, signals provided by ROS also play a
significant role in increasing complexity. Furthermore, slightly elevated white
blood cells (WBCs) count has been reported to be significantly associated with
stressful lifestyles (Al-Hatamlehet al., 2020). On the other hand, the red blood
cells (RBCs) are continuously facing ROS from exogenous and endogenous
sources, which can lead to insufficient RBCs functions and destruction. Stress
by its correlation with oxidative stress, can result to malabsorption of hematinic
factors such as iron, vitamin B12, and folic acid, which in turn, may lead to
RBC integrity and erythropoiesis disorders (Al-Hatamlehet al., 2020).
2.4 Laboratory Diagnostic Methods
2.4.1 Haemoglobin Concentration and Erythrocyte Indices:
Haemoglobin concentration and erythrocyte indices, including mean
corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), and mean
corpuscular haemoglobin concentration (MCHC), serve as primary indicators of
erythropoietic activity and oxygen-carrying capacity. Chronic stress may result
in anaemia secondary to suppression of erythropoiesis, leading to decreased
haemoglobin levels and microcytic or normocytic erythrocyte morphology.
Monitoring changes in haemoglobin concentration and erythrocyte indices
enables the assessment of stress-induced alterations in red blood cell production
and maturation (Joseph et al., 2024).
2.4.2 White Blood Cell Count and Leukocyte Differential:
White blood cell count and leukocyte differential provide valuable insights into
the immune response to chronic stress. Stress-induced activation of the immune
system may manifest as leukocytosis, characterized by an elevation in total
white blood cell count and differential leukocyte counts. Differential analysis
allows for the identification of specific leukocyte subsets, including neutrophils,
lymphocytes, monocytes, eosinophils, and basophils, each of which plays a
distinct role in the inflammatory and immune response to stressors (Joseph et
al., 2024).
2.4.3 Laboratory Determination of Lead Poisoning
Several laboratory methods can be employed to determine the amount of lead in
whole blood. These methods may include the following
Atomic Absorption Spectrometry (AAS)
The principle of the AAS is that free atoms absorb light at specific wavelengths.
The amount of absorbed light can be correlated in a linear fashion to
theconcentration of the analyte present in the sample. In order to perform an
AAS measurement for lead, the sample must first be processed to generate
ground-state atoms as vapour within the light path of the instrument. This
process is known as atomization and can be done with a flame, (flame atomic
absorption spectrometry, FAAS) or electro-thermal source, most often a graphite
furnace (graphite furnace atomic absorption spectrometry, GFAAS) (World
Health Organization, 2018). The flame atomic absorption spectrometry makes
use of an acetylene–air or a nitrous oxide–acetylene–air laminar flame to
atomize lead at temperatures ranging between 2000–3000 °C (World Health
Organization, 2018). This method is relatively cheaper, simple to use and free
from interferences. The GFAAS uses an electrically heated graphite tube to
vaporize and atomize the analyte at temperatures up to 3000 °C prior to its
detection. It is a very sensitive method but subject to interferences. These
interferences have been reduced by enhanced instrument design in addition to
using matrix modifiers. Improved instrument design also makes it possible to
detect BLLs as low as 1μg/dl with the AAS. Smaller sample volumes between
10–50 μl can also be measured by this method (World Health Organization,
2018).
Anodic Stripping Voltammetry (ASV)
With the ASV method of estimating blood lead, a standard electrode and a thin-
film mercury graphite electrode are placed in the blood sample, followed by a
negative potential application to the mercury electrode for few seconds causing
the lead in the blood sample and other cations present to accumulate on the
surface of the mercury electrode which is negatively charged (World Health
Organization, 2018). The potential’s direction is then reversed to yield a
progressively higher potential over several minutes. All other ions are released
from the electrode when a specific characteristic lead voltage is reached. A
measureable current which is directly proportional to the number of lead ions
released is produced. This is then compared with calibration solutions to
evaluate the lead concentration in the blood sample (World Health Organization,
2018). This method requires sample preparation because the lead has to be
available as free Pb2+ aqueous cation. These ASV devices have a detection
limit between 1–100μg/dl. Portable ASV devices (example, lead care device)
are available for use on the field and also as a point of care device. It is
recommended that BLLs greater than 10μg/dl are confirmed with either the
AAS or ICP-MS. The presence of co-reducible metals and chelating agents or
elevated copper concentrations can create interferences. Small sample volumes
of 50μl are used (World Health Organization, 2018).
Inductively Coupled Plasma Mass Spectrometry (ICP-MS)
This method involves the use of inductively coupled plasma to atomize and
subsequently ionize the atoms of interest in the sample. Extraction of the ions
from the plasma is done and they are passed through a mass spectrometer. In the
mass spectrometer, the ions are separated and measured based on their mass-to-
charge ratio. The ICP-MS has a high selectivity of filters of ions in addition to
highly amplified ionic signals that strike the detector. It also has low
background interferences with noise and offers very minute detection limits
(part per trillion to part per billion) for majority of elements (World Health
Organization, 2018). The ICP-MS method has a detection limit of nearly 0.2
μg/dl for direct analysis of lead in blood. Blood sample dilution before
aspiration into the plasma is very vital because ICP-MS is less tolerable relative
to AAS of heavy matrices. Based on this, highest standard of operation by
skilled personnel is required for the operation of ICP-MS. The ICP-MS can
evaluate several elements from a lone sample volume as low as 50–100 μl and
also permits the measurement of the lead isotope ratio present in the blood
sample. This makes it feasible in making out whether the lead was from a
specific location. The ICP-MS is expensive though highly productive and
therefore, becomes relatively economical in analysing many samples or
elements (World Health Organization, 2018).
The AAS method for the detection of blood lead was adopted for this study. The
reason being that it is relatively cheaper and available and also has a high
detection limit as well as a low detection limit of above 100μg/dl and 1μg/dl
respectively. It can also analyse smaller sample volumes of 10 to 50μl.
Improvement in instrument designs has also reduced the problem with
interferences.
CHAPTER THREE
MATERIALS AND METHODS
3.1 Study Area
The study was carried out at the Haematology Laboratory of Abia State
Teaching Hospital (ABSUTH) located at Umueze Road Abayi, in the town of
Aba. Aba is a city found in the Southeast geopolitical zone of Nigeria and lie
between Latitude 5̊ 25'N 7˚30'E and longitude 5̊ 45'N 7˚52’E and about 48km
from Umuahia, also it is the commercial centre of Abia state. It is a major urban
settlement and surrounded by small villages and towns. The indigenous people
are the Ngwa.
3.2 Study Design
This was a cross-sectional study involving tricycle drivers in Aba metroplolis.
3.3 Sample Size
The study size was determined by using the Fischers’ Formula, with the
prevalence rate of 93% giving a sample size of one hundred (100) subjects. A
total sample size of 100 subjects were recruited for this study.
Sample size was calculated using the formula below:
n = =
where: n = the minimum sample size
Z = the standard normal deviation, usually set at 1.96, which corresponds to the
95% confidence interval
p = the prevalence rate of 93% (0.93)
q = 1- P
d = degree of accuracy desired usually set at 0.05
The required sample size was calculated as follows:
n =
n =
n =
n = = 100
n = 100
The total sample size of 100(50 subjects and 50 controls) were recruited for the
study.
3.4Sampling Technique
A Simple random sampling technique was adopted for this study.
3.5Inclusion Criteria
This study included; apparently healthy tricycle drivers with no adverse medical
history, consenting tricycle drivers, and healthy non-tricycle drivers as control.
3.6Exclusion Criteria
This study excluded subjects with; denial of consent, febrile illness in the last
four weeks, features or laboratory diagnosis of haemoglobinopathy or bleeding
disorder, chronic medical ailment, record of recent blood transfusion, and acute
renal, liver or systemic diseases.
3.7Ethical Approval
Ethical approval to carry out the study was obtained from the Ethical committee
of the Department of Medical Laboratory Science, Abia State Teaching
Hospital.
3.8Sample Collection and Preparation
Five milliliters of blood (5 ml) was collected. The 5ml of blood was used for the
determination of haematological parameters count using an Automated- Full
blood count analyzer.
3.9Laboratory Methods
Determination of Complete blood Count Using Automated Analyser.
Principle:
Hemia 5D is a quantitative automated hematology analyzer for in vitro
diagnostic use for determining 17 hematological parameters. Examination of the
numerical and/or morphologic findings of the complete blood count are useful
in diagnosis of such disease states as anemias, leukemias, allergic reactions,
viral, bacterial, and parasitic infections. Hemia 5D directly measures the WBC,
RBC, HGB, HCT, PLT, LYM, MIXED and NEUT. The KX-21N counts and
sizes red blood cells (RBC) and platelets (PLT) using electronic resistance
detection. Hematocrit (HCT) is measured as the ratio of the total RBC volume
to whole blood using cumulative pulse height detection. Hemoglobin (HGB) is
converted to methemoglobin, and read photometrically at 555 nm.
White blood cells (WBC) are analyzed by direct current and discriminated into
a three-part differential using Particle Distribution Analysis (PDA). The
resulting WBC histogram is discriminated into lymphocyte, neutrophil and
mixed cell populations. The mixed cell population contains monocytes,
basophils and eosinophils
Procedure:
The automatic voltage regulator, the uninterrupted power supply unit and the
power button on the Hemmia 5D Haematologyanalyser were turned on. The
“ready” for analysis was allowed to appear and there was a temporary wait for
the analyzer to come to “ready state”. Then, the sample numbers of the subject
entered into the device. Five millilitres (5 ml) of blood collected in K3EDTA
vacutainer was mixed gently. The stopper of the vacutainer was opened to start
analysis. The tube was set to the sample probe and the start switch was pressed
so that the device can aspirate the required volume. The tube was held against
the sample probe until the buzzer sounds twice. At the end of each analysis, the
device displays and prints a hard copy of the report for onward documentation.
After the printing, it goes to ready state so that it can analyze another sample.
3.10Statistical Analysis
The data analysis was performed using Statistical Package for Social Science
(SPSS) version 25.0. The parameters were expressed in mean and standard
deviation. Comparison of groups was done using ANOVA and Student’s t-test.
Level of significance was set at p0.05- Not Significant.
4.2 The mean and standard deviation of haemoglobin concentration (HB), packed cell
volume (PCV), red blood cell (RBC), platelet (PLT), total white blood cell (TWBC),
neutrophil (NEUT), lymphocyte (LYM), monocyte (MON), basophil (BAS), eosinophil
(EOS), mean cell volume (MCV), mean cell haemoglobin (MCH), and mean cell
haemoglobin concentration (MCHC) of tricycle drivers based on age recruited into the study
was shown in table 4.2, using ANOVA and Post HOC. The mean ± standard deviation values
of HB (12.93±1.449, 12.23±1.354, 12.36±1.287, respectively) g/dl of tricycle drivers aged
20-29, 30-39, & 40 years above, respectively, were not statistically significant (P>0.05). The
mean ± standard deviation values of PCV (0.40±4.089, 0.38±3.652, 0.39±6.118,
respectively)L/L of tricycle drivers aged 20-29, 30-39, & 40 years above, respectively, were
not statistically significant (P>0.05). The mean ± standard deviation values of RBC
(4.57±0.550, 4.46±0.499, 4.51±0.827, respectively) x1012
/L of tricycle drivers aged 20-29,
30-39, & 40 years above, respectively, were not statistically significant (P>0.05). The mean ±
standard deviation values of PLT (190.25±48.716, 188.20±33.184, 199.21±42.403,
respectively) x109/L of tricycle drivers aged 20-29, 30-39, & 40 years above, respectively,
were not statistically significant (P>0.05). The mean ± standard deviation values of TWBC
(4.77±0.982, 5.26±1.284, 4.80±0.845, respectively) x109
/L of tricycle drivers aged 20-29, 30-
39, & 40 years above, respectively, were not statistically significant (P>0.05). The mean ±
standard deviation values of NEUT (2.15±0.667, 2.55±0.607, 2.21±0.981, respectively)
x109/L of tricycle drivers aged 20-29, 30-39, & 40 years above, respectively, were not
statistically significant (P>0.05). The mean ± standard deviation values of LYM (1.75±0.359,
1.93±0.037, 1.83±0.524, respectively) x109
/L of tricycle drivers aged 20-29, 30-39, & 40
years above, respectively, were not statistically significant (P>0.05). The mean ± standard
deviation values of MON (0.58±0.033, 0.64±0.124, 0.61±0.077respectively) x109
/L of
tricycle drivers aged 20-29, 30-39, & 40 years above, respectively, were not statistically
significant (P>0.05). The mean ± standard deviation values of BAS (0.21±0.231, 0.33±0.421,
0.22±0.012, respectively) x109
/L of tricycle drivers aged 20-29, 30-39, & 40 years above,
respectively, were not statistically significant (P>0.05). The mean ± standard deviation values
of EOS (0.11±0.023, 0.12±0.043, 0.12±0.064, respectively)x109
/L of tricycle drivers aged
20-29, 30-39, & 40 years above, respectively, were not statistically significant (P>0.05). The
mean ± standard deviation values of MCV (86.83±4.355, 85.40±2.074, 86.51±6.455,
respectively) fl of tricycle drivers aged 20-29, 30-39, & 40 years above, respectively, were
not statistically significant (P>0.05). The mean ± standard deviation values of MCH
(29.33±1.366, 27.60±2.302, 30.25±0.957, respectively) pg of tricycle drivers aged 20-29, 30-
39, & 40 years above, respectively, were not statistically significant (P>0.05). The mean ±
standard deviation values of MCHC (32.01±1.41, 32.17±0.983, 30.53±2.944, respectively)
g/dl of tricycle drivers aged 20-29, 30-39, & 40 years above, respectively, were not
statistically significant (P>0.05).
TABLE 4.2: COMPARISON OF MEAN±SD OF HB, PCV, PLT, TWBC,
NEUT, LYM, MON, BAS, EOS, MCV, MCH, MCHC OF TRICYCLE
DRIVERS BASED ON AGE .
Parameters 20-29 years 30-39 years 40 and above F
ratio
P
value
HB (g/dl) 12.93±1.449 12.23±1.354 12.36±1.287 0.465 0.639
PCV (L/L) 0.40±4.089 0.38±3.652 0.39±6.118 0.210 0.814
RBC
(x1012/L)
4.57±0.550 4.46±0.499 4.51±0.827 0.345 0.786
PLT
(x109/L)
190.25±48.716 188.20±33.184 199.21±42.403 2.307 0.142
TWBC
(x109/L)
4.77±0.982 5.26±1.284 4.80±0.845 0.338 0.719
NEUT
(x109/L)
2.15±0.667 2.55±0.607 2.21±0.981 0.084 0.920
LYM
(x109/L)
1.75±0.359 1.93±0.037 1.83±0.524 0.387 0.687
MON 0.58±0.033 0.64±0.124 0.61±0.077 1.038 0.369
(x109/L)
BAS
(x109/L)
0.21±0.231 0.33±0.421 0.22±0.012 0.835 0.458
EOS
(x109/L)
0.11±0.023 0.12±0.043 0.12±0.064 0.238 0.962
MCV (fl) 86.83±4.355 85.40±2.074 86.51±6.455 0.352 0.710
MCH (pg) 29.33±1.366 27.60±2.302 30.25±0.957 3.014 0.087
MCHC
(g/dl)
32.01±1.414 32.17±0.983 30.53±2.944 2.510 0.123
Key: P≤0.05 – Significant, P>0.05- Not Significant.
Multiple Comparisons
LSD
Dependent
Variable (I) Variable (J) Variable Mean Difference (I-J) Std. Error Appendix. 95% Confidence Interval
Lower
Bound
Upper
Bound
HB 20-29 30-39 .91333 1.01191 .385 -1.2914 3.1181
40 above .08333 1.07870 .940 -2.2669 2.4336
30-39 20-29 -.91333 1.01191 .385 -3.1181 1.2914
40 above -.83000 1.12102 .473 -3.2725 1.6125
PCV 20-29 30-39 1.78000 2.75953 .531 -4.2325 7.7925
40 above .65000 2.94167 .829 -5.7593 7.0593
30-39 20-29 -1.78000 2.75953 .531 -7.7925 4.2325
40 above -1.13000 3.05707 .718 -7.7908 5.5308
RBC 20-29 30-39 -.00667 .37320 .986 -.8198 .8065
40 above -.00667 .39783 .987 -.8735 .8601
30-39 20-29 .00667 .37320 .986 -.8065 .8198
40 above .00000 .41344 1.000 -.9008 .9008
PLT 20-29 30-39 45.80000 25.72897 .100 -10.2586 101.8586
40 above -9.00000 27.42718 .748 -68.7587 50.7587
30-39 20-29 -45.80000 25.72897 .100 -101.8586 10.2586
40 above -54.80000 28.50316 .079 -116.9030 7.3030
TWBC 20-29 30-39 -.49167 .64346 .460 -1.8936 .9103
40 above -.03417 .68593 .961 -1.5287 1.4603
30-39 20-29 .49167 .64346 .460 -.9103 1.8936
40 above .45750 .71284 .533 -1.0956 2.0106
NEUT 20-29 30-39 .70667 6.44964 .915 -13.3459 14.7592
40 above -2.13333 6.87534 .762 -17.1134 12.8467
30-39 20-29 -.70667 6.44964 .915 -14.7592 13.3459
40 above -2.84000 7.14506 .698 -18.4078 12.7278
LYM 20-29 30-39 -3.06667 4.39629 .499 -12.6454 6.5120
40 above -3.66667 4.68647 .449 -13.8776 6.5443
30-39 20-29 3.06667 4.39629 .499 -6.5120 12.6454
40 above -.60000 4.87032 .904 -11.2115 10.0115
MON 20-29 30-39 -2.13333 1.64799 .220 -5.7240 1.4573
40 above -2.08333 1.75677 .259 -5.9110 1.7443
30-39 20-29 2.13333 1.64799 .220 -1.4573 5.7240
40 above .05000 1.82568 .979 -3.9278 4.0278
BAS 20-29 30-39 -.30000 .56100 .603 -1.5223 .9223
40 above .50000 .59803 .419 -.8030 1.8030
30-39 20-29 .30000 .56100 .603 -.9223 1.5223
40 above .80000 .62149 .222 -.5541 2.1541
EOS 20-29 30-39 .02667 .37390 .944 -.7880 .8413
40 above -.08333 .39858 .838 -.9518 .7851
30-39 20-29 -.02667 .37390 .944 -.8413 .7880
40 above -.11000 .41422 .795 -1.0125 .7925
MCV 20-29 30-39 .43333 2.69122 .875 -5.4303 6.2970
40 above 2.33333 2.86885 .432 -3.9174 8.5840
30-39 20-29 -.43333 2.69122 .875 -6.2970 5.4303
40 above 1.90000 2.98140 .536 -4.5959 8.3959
MCH 20-29 30-39 1.73333 1.00846 .111 -.4639 3.9306
40 above -.91667 1.07502 .411 -3.2589 1.4256
30-39 20-29 -1.73333 1.00846 .111 -3.9306 .4639
40 above -2.65000 1.11720 .055 -5.0842 -.2158
MCHC 20-29 30-39 .16667 .97063 .867 -1.9482 2.2815
40 above 2.16667 1.03470 .058 -.0877 4.4211
30-39 20-29 -.16667 .97063 .867 -2.2815 1.9482
40 above 2.00000 1.07529 .088 -.3429 4.3429
4.3 The mean and standard deviation of haemoglobin concentration (HB),
packed cell volume (PCV), red blood cell (RBC), platelet (PLT), total white
blood cell (TWBC), neutrophil (NEUT), lymphocyte (LYM), monocyte (MON),
basophil (BAS), eosinophil (EOS), mean cell volume (MCV), mean cell
haemoglobin (MCH), and mean cell haemoglobin concentration (MCHC) of
tricycle drivers based on duration of use recruited into the study was shown in
table 4.3, using student’s t-test. The mean ± standard deviation values of HB,
PCV, RBC, PLT, MON, EOS, MCV, MCHC (12.68±1.884g/dl, 0.39±4.915L/L,
4.57±0.656x1012/L, 185.32±58.581x109/L, 0.76±0.321x109/L,
0.15±0.051x109/L, 86.56±3.468fl, 31.67±1.414g/dl, respectively) of subjects
that have been driving tricycle for 1-4 years were higher but not statistically
significant (P>0.05) when compared with the values of subjects who have been
driving tricycle for 5 years and above (12.56±1.238g/dl, 0.38±3.591L/L,
4.41±0.450x1012/L, 175.33±45.148x109/L, 0.65±0.265x109/L,
0.13±0.043x109/L, 85.33±2.465fl, 31.33±2.338g/dl, respectively). The mean ±
standard deviation values of TWBC, NEUT, LYM, BAS, MCH
(4.84±0.898x109/L, 2.12±0.697x109/L, 0.41±0.237x109/L, 28.89±2.315 x109/L,
respectively) of subjects that have been driving tricycle for 1-4 years were lower
but not statistically significant (P>0.05) when compared with the values of
subjects who have been driving tricycle for 5 years and above
(5.09±1.236x109/L, 2.95±0.496x109/L, 1.45±0.676x109/L, 0.43±0.124x109/L,
29.17±1.169pg, respectively).
TABLE 4.3: COMPARISON OF MEAN±SD OF HB, PCV, PLT, TWBC,
NEUT, LYM, MON, BAS, EOS, MCV, MCH, MCHC OF TRICYCLE DRI
VERS BASED ON DURATION OF DRIVING USING STUDENT T-TEST.
Parameters 1-4 years 5 years above Calculated t P value
HB (g/dl) 12.68±1.884 12.56±1.238 0.146 0.886
PCV (L/L) 0.39±4.915 0.38±3.591 0.095 0.926
RBC (x1012/L) 4.57±0.656 4.41±0.450 0.544 0.596
PLT (x109/L) 185.32±58.581 175.33±45.148 1.796 0.441
TWBC (x109/L) 4.84±0.898 5.09±1.236 -0.457 0.655
NEUT (x109/L) 2.12±0.697 2.95±0.496 -0.215 0.833
LYM (x109/L) 1.23±0.322 1.45±0.676 -0.443 0.665
MON (x109/L) 0.76±0.321 0.65±0.265 1.085 0.298
BAS (x109/L) 0.41±0.237 0.43±0.124 -1.840 0.092
EOS (x109/L) 0.15±0.051 0.13±0.043 1.928 0.076
MCV (fl) 86.56±3.468 85.33±2.465 0.534 0.603
MCH (pg) 28.89±2.315 29.17±1.169 -0.269 0.792
MCHC (g/dl) 31.67±1.414 31.33±2.338 0.346 0.735
Key: P≤0.05 – Significant, P>0.05- Not Significant.
CHAPTER FIVE
DISCUSSION, CONCLUSION, RECOMMENDATION
5.1 Discussion
The nature of work and lifestyle of commercial cyclists predisposes them to
various conditions that can lead to anaemia, which in turn affect haematopoiesis
and cause morbidity and mortality (Olayanjuet al., 2021).
The findings of this present study showed a statistically significant (P≤0.05)
reduction in haemoglobin concentration, packed cell volume and red blood cells
of tricycle drivers when compared with non-tricycle drivers. This is similar with
the findings of Olayanjuet al. (2021) which found haemoglobin to be
significantly lower among tricycle drivers. Similarly, a study carried out in
Owerri, Nigeria on the effect of chronic alcohol consumption on
haematologicaland cardio hepatic function markers among commercial
motorcyclists, showed that Haemoglobin was significantly lower in
motorcyclists (Igbohet al., 2015). Tricycle drivers are often exposed to higher
levels of environmental pollutants such as carbon monoxide, lead, and other
particulate matter. These pollutants can cause oxidative stress, leading to
haemolysis (destruction of red blood cells) and a consequent reduction in
haemoglobin levels and RBC count. Tricycle drivers may have less access to a
balanced diet due to economic constraints, leading to deficiencies in essential
nutrients such as iron, vitamin B12, and folic acid, which are crucial for
erythropoiesis (the production of red blood cells). This can result in lower
haemoglobin, PCV, and RBC levels.
In this study, platelet count was statistically lower (P≤0.05) in tricycle drivers
when compared with non-tricycle drivers. This is consistent with the findings of
Olayanjuet al. (2021). Tricycle drivers are constantly exposed to high levels of
vehicular emissions, including particulate matter (PM), carbon monoxide (CO),
nitrogen oxides (NOx), and sulfur dioxide (SO2) (Ulakpa and Ulakpa, 2022).
Chronic exposure to these pollutants can lead to systemic inflammation and
oxidative stress (Gangwaret al., 2020). Oxidative stress and inflammation can
impair megakaryocytes (the precursor cells of platelets), leading to reduced
platelet production (Noh, 2022). This may also be associated with nutritional
deficiency. ROS is known to deplete antioxidants and depletion of antioxidants
render blood cells very fragile, thus leading to accelerated destruction of the
blood cells (Igbohet al., 2015).
In this study, white blood cells were higher among tricycle drivers compared to
non-tricycle drivers but this was not statistically significant (P>0.05). This was
in contrast with the findings of Olayanjuet al. (2021) which observed lower
white blood cells among tricycle drivers, although without a statistical
significance (P>0.05). Igbohet al. (2015) also found lower levels of white blood
cells in motorcyclists.
Chnages in haematological parameters among tricyclists were not associated
with age and duration of use of tricycle. Tricycle drivers are consistently
exposed to similar levels of pollutants and physical strain, which may result in
relatively uniform haematological profiles over different durations of exposure.
5.2 Conclusion
This study revealed significant hematological differences between tricycle
drivers and non-tricycle drivers, particularly in parameters such as haemoglobin
concentration (HB), packed cell volume (PCV), red blood cell (RBC) count,
platelet (PLT) count, and mean cell volume (MCV). Tricycle drivers exhibited
lower levels of these parameters, which were statistically significant. Factors
contributing to these findings include chronic exposure to environmental
pollutants, physical and psychological stress, nutritional deficiencies, and
limited healthcare access. These results underscore the need for targeted
interventions to improve the health and working conditions of tricycle drivers.
5.3 Recommendation
Based on the findings of this study, several interventions are recommended to
address the health disparities observed among tricycle drivers:
1. Implement regular health check-ups for tricycle drivers to monitor their
hematological parameters and overall health. Early detection of abnormalities
can lead to timely interventions.
2. Provide training on occupational safety, including the use of personal
protective equipment (PPE) like masks to reduce exposure to pollutants.
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APPENDIX I
INFORMED CONSENT FORM
I…………………………………………………………………. of……………
……………………………………………………………………………………
……….. do hereby consent to participate in this study titled: “Assessment of Some
Haematologic Parameters Among Tricycle Drivers in Aba, Abia State, Nigeria” I
acknowledge that I have been properly counseled on the implications of my involvement. I
understand that the investigations that would be carried out in the course of this study are
solely for the purpose of medical research and I express my willingness to participate on the
understanding that I shall be entitled to withdraw this consent at any time I choose to do so
and that my withdrawal will not affect the quality of care I received in the hospital.
Date…………………… Signed ………………… Witness…………………...
I confirm that I have explained to the patient the purpose and nature of this study and
his/her refusal to participate will not in any way affect the normal care by me or any member
of this institution. I know the consequences of any false declaration on this or any other form.
Date……………………… Signed…………………… Witness…………………...
APPENDIX II
Equipment Model Manufacturer
General laboratory glass wares and
Test tube Racks
Pyrex Corning England
Automatic pipettes and tips
Full blood count automated
analyser
Sysmex KX-21N Sysmex Germany
Sample Containers (K3EDTA 5ml
vacutainer tube) and disposable
needle
KRIS17-759G KRIS-ALOY
Spirit alcohol and Cotton wool
Reagents Product Number Description
Sysmex Reagents
• Diluent)
Sodium Chloride 6.38g/L
Sysmex F820/KX-
21N/
Zhejiang Xinke Medical
Technology co., Ltd.
Boric Acid
1.00g/L
Sodium Tetraborate 0.20g/L
EDTA-2K 0.20g/L
• HaemoglobinLyser
Organic quanternary
ammonium salt
8.5g/L
Sodium Chloride 0.6g/L
• Cell cleaning Solution-Bleach
Sodium Hypochlorite 8.25%
APPENDIX III
APPENDIX IV
STATISTICAL ANALYSIS
Arithmetic Mean
x = mean
= summation
Different values that make up the set
N = Number of data (sample size)
Standard deviation
SD=
SD = Standard Deviation
= mean
= summation
Different values that make up the set
(n1 + n2) – 2 = absolute degree of freedom
Student’s T-test
“t” =
Where “t” = Student’s T-test
= Mean of group one
= Mean of group two
SD1 Standard Deviation of regular donors
SD2 = Standard Deviation of control.
ANOVA (Analysis of Variance)
F = MST/MSE
MST = SST/ p-1
MSE = SSE/N-p
SSE = ∑ (n−1)
2
Where,
F = Anova Coefficient
MSB = Mean sum of squares between the groups
MSW = Mean sum of squares within the groups
MSE = Mean sum of squares due to error
SST = total Sum of squares
p = Total number of populations
n = The total number of samples in a population
SSW = Sum of squares within the groups
SSB = Sum of squares between the groups
SSE = Sum of squares due to error
s = Standard deviation of the samples
55
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