|Ahead of print publication
Evaluation of spiro metric parameters in traffic police men in a Metropolitan City
Santosh Rohidas Bokre1, Sangita Deshpande2, Anil Raosaheb Waghmare3, Anjali Shete1
1 Department of Physiology, GMC and GH, Baramati, Maharashtra, India
2 Department of Physiology, BJGMC and GH, Pune, Maharashtra, India
3 Department of Physiology, GMC and GH, Aurangabad, Maharashtra, India
|Date of Submission||14-Feb-2022|
|Date of Decision||09-Mar-2022|
|Date of Acceptance||10-Mar-2022|
Professor and Head, Department of Physiology, GMC and GH, Baramati, Maharashtra
Source of Support: None, Conflict of Interest: None
Introduction: Air pollution is a major environment related health threat. Air quality crisis in Indian cities is mainly due to emission from vehicles which include various particles and gases from vehicular emission. Traffic policemen who work in the busy traffic signal areas for years together are constantly exposed to this pollutant making them susceptible to its adverse effects, like respiratory and cardiovascular diseases. Objectives: To compare different parameters of pulmonary function test (PFT) between non-smoker controls and non-smoker traffic policemen, and also between smoker controls and smoker traffic policemen.Methods: This study was carried out in Department of Physiology among the government servants not exposed to traffic pollution and traffic policemen exposed to vehicular pollution. PFT was conducted in both these groups and parameters like vital capacity (VC), FEV1-force expiratory volume at the end of 1 second, ratio of forced expiratory volume at first second to forced vital capacity (FEV1/FVC%), mid-expiratory flow rate (FEV25-75%) and peak expiratory flow rate (PEFR) were measured and compared between these two groups. Results: In the present study, traffic policemen (non smoker) showed a statistically significant reduction in VC, FEV1, FEV1/FVC%, FEV25-75, and PEFR compared to controls (non smoker) whereas traffic policemen (smoker) showed a statistically significant reduction in VC, FEV1, FEV1/FVC%, FEV25-75%, and PEFR compared to controls (smoker).Conclusion: Significant reduction in all the parameters in traffic policemen compared to control group proves that preventive measures like pollution masks, regular breathing exercises, etc., have to be implemented at the workplace to reduce health hazards of continuous exposure to traffic dust.
Keywords: Non smokers, pulmonary function test, smokers, traffic policemen
|How to cite this URL:|
Bokre SR, Deshpande S, Waghmare AR, Shete A. Evaluation of spiro metric parameters in traffic police men in a Metropolitan City. Med J DY Patil Vidyapeeth [Epub ahead of print] [cited 2022 Dec 6]. Available from: https://www.mjdrdypv.org/preprintarticle.asp?id=346443
| Introduction|| |
Air pollution is a major environment-related health threat. The air quality crisis in Indian cities is mainly due to emissions from vehicles which include various particles and gases from vehicular emission. Association between air pollution and health was established in the 20th century during the occurrence of major air-pollution episodes, which were followed by an increase in mortality and morbidity. According to a European assessment, air pollution accounts for 6% of all mortality1 and 50% of this mortality is due to air pollution accounted by vehicular pollution. The toxic chemicals and gases released from vehicular emission produce irritation and allergy in the lungs and air passage of individuals who are exposed to it for a long time. The majority of today's cars and trucks travel by using internal combustion engines that burn gasoline or other fossil fuels. Emissions that are released directly into the atmosphere from the tailpipes of cars and trucks are the primary source of vehicular pollution. Motor vehicles also pollute the air during the processes of manufacturing, refueling, and from the emissions associated with oil refining. Acute effects of diesel exhaust exposure include irritation of the eyes and nose, lung function changes, headache, fatigue, and nausea. Chronic exposure is associated with cough, sputum production, and lung function decrements. In the long run, the pollutants may produce diseases like asthma and bronchitis in the exposed individuals with changes in normal lung functions. SO2 and NO2 inhalation cause bronchoconstriction, mucosal irritation, and alveolar swelling leading to obstructive, restrictive, or combined disorder of the lung. These air pollutants interact with epithelial cells and macrophages causing activation and release of mediators like interleukin-1, TNF, fibronectin, lipid mediators, O2 derived free radicals, fibrogenic cytokines leading to collagen accumulation and fibrosis. This pathogenesis is in the form of small airway involvement and restrictive impairment by altering the properties and concentration of surfactant. The prevalence of the obstructive, restrictive, and mixed type of functional impairment of lung was found to have a direct relationship with the dust concentration and duration of exposure.
Traffic policemen are continuously exposed to vehicular emissions, dust, and other pollutants without any preventive measures which make them susceptible and account for compromised lung functions. Since occupation is a major determinant of health, traffic police personnel face multiple occupational hazards. They work in noisy and polluted environments. Standing for long hours in a static position makes them vulnerable to ergonomic problems. They manage high volumes of traffic density which results in physical and mental fatigue making them susceptible to physical and mental stress. Both physical and mental health manifestations get accentuated with the increasing length of service. Poor interpersonal relationships, lack of adequate personal time, 10-12 hours daily shift schedules that disrupt normal sleep patterns and social life are the other few stressors faced by members of the police force.
Hence the study was undertaken to compare different parameters of pulmonary function test (PFT) in traffic policemen to see the effect of smoking on these pulmonary functions.
| Methods|| |
Ethical committee approval is obtained. October 2017 BJMC Pune Ethics committee.
The study is a cross sectional type. The sample size was calculated by this formula.
Z = Constant = 1.96, P = Prevalence rate, Q = 1 – P, R2 = Constant = 5/0.5
All the subjects with ages between 20 to 50 years were selected and divided into two groups, each of 130 subjects which are further divided into two subgroups as smokers and non smokers. The smoker group was selected on the basis of the duration of cigarettes smoked since 3 years and 4-6 cigarettes per day.
- Group 1:
- 130 male policemen engaged in traffic control in the age group from 20 to 50 years from local stations having exposure to dust for at least 5-7 hours/day.
- They were selected from local traffic Stations.
- They did not use any self protection measures to avoid exposure to dust
Group 2 (Controls):
- Apparently healthy male subjects in the age group from 20 to 50 years serving in Govt. Medical College as nursing orderlies, pharmacists, and other technical staff but not exposed to traffic pollution were taken as controls.
Traffic Policemen were individually matched for age, height, and weight with controls. Control subjects were of the similar socioeconomic group, assessed by a questionnaire.
- 130 subjects were taken in Group 1.
- 130 subjects were taken in Group 2.
- Apparently healthy male subjects in the age group from 20 to 50 years serving in Govt. Medical College as nursing orderlies, pharmacists, and other technical staff but not exposed to traffic pollution
- 130 male policemen engaged in traffic control in the age group from 20 to 50 years from local stations having exposure to dust for at least 5-7 hours/day.
Exclusion criteria are the same for Group 1 and Group 2
- Known case of hypertension, ischemic heart disease, myocardial infarction, diabetes mellitus, alcoholic liver disease, ascites, and hepatosplenomegaly.
- Trauma to chest and thorax surgery in the past.
- Congenital \ Acquired chest or spine deformity like kyphosis, scoliosis, pigeon chest, etc
- Subjects having H/o acute or chronic respiratory infections, current or previous drug reactions, cardiopulmonary, neuromuscular disease, malignancy, diabetes mellitus, major abdominal or chest surgery.
- The study was conducted in the Department of Physiology, IEC approval was taken.
- The procedure was explained and informed consent was obtained.
Demographic parameters were recorded in both groups [Table 1].
- Age: The present age of the subject in complete years was noted down.
- Height: Bare foot standing height is recorded in centimetres.
- Weight: Was recorded in kilograms.
PFT Parameters: Two consecutive sputum samples were tested before performing pulmonary function tests to rule out tuberculosis. PFT was recorded using “HELIOS 702 (RMS, INDIA) SPIROMETER MACHINE.”
All tests were carried out at a fixed time of the day to minimize the diurnal variations. The apparatus was calibrated daily and was operated within the ambient temperature range. The precise technique of executing various lung function tests was based on the operational manual of the instrument and the recommendations which were made by the American thoracic society for a standard technique of spirometry. The data record was reproduced as a PFT report.
The sitting position was preferred for the subject. Pneumotach was fitted tightly in the mouth with teeth and lips to avoid leakage of air. A nose clip was used to prevent leakage of air from the nose. The test procedure was explained to the subject. PFT was conducted in both these groups and parameters like vital capacity (VC), FEV1-Force expiratory volume at the end of 1 second, ratio of forced expiratory volume at first second to forced vital capacity (FEV1/FVC%), mid-expiratory flow rate (FEV25-75%) and peak expiratory flow rate (PEFR) were measured and compared between these two groups. The Parameters used in these two groups for comparison on PFT were.
- VC-Vital capacity
- FEV1-Force expiratory volume at the end of 1 second
- FEV1/FVC Ratio
- FEF25-75%-Mid expiratory flow rate.
- PEFR-Peak expiratory flow rate.
The PFT parameters were compared in both the groups but the intergroup smoker and non smoker comparison was not done.
| Observation and Results|| |
In the present study, we found that mean levels of vital capacity (VC) in non smoker traffic policemen group (2.05 ± 1.16) was lower than non smoker Control group (2.55 ± 0.86). This difference was statistically significant (P = 0.0007) when compared by using an unpaired t test. Mean levels of vital capacity (VC) in smoker traffic policemen group (1.47 ± 0.06) was also found lower than Smoker Control group (2.32 ± 0.88) and the difference was statistically significant (P < 0.0001) when compared by using unpaired t test [Table 2].
|Table 2: Mean VC, FEV1 (L), FEV1/FVC%, FEV25-75%, PEFR in two study groups|
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In the present study, mean levels of forced expiratory volume (FEV1) in non smoker traffic policemen group (2.25 ± 0.59) was lower than non smoker control group (2.58 ± 0.62). This difference was statistically significant (P = 0.0002) when compared by using an unpaired t test. Mean levels of forced expiratory volume (FEV1) in smoker traffic policemen group (1.87 ± 0.56) was also found lower than Smoker Control group (2.05 ± 0.71) and the difference was not statistically significant (P = 0.2801) when compared by using unpaired t test.
In the present study mean levels of ratio of forced expiratory volume/forced vital capacity (FEV1/FVC %) in non smoker traffic policemen group (86.18 ± 6.96) was lower than non Smoker Control group (89.98 ± 6.28). This difference was statistically significant (P < 0.0001) when compared by using an unpaired t test. Mean levels of ratio of Forced Expiratory Volume/Forced Vital Capacity (FEV1/FVC %) in Smoker traffic policemen group (78.8 ± 4.78) was also found lower than Smoker Control group (85.86 ± 5.32) and the difference was statistically significant (P < 0.0001) when compared by using unpaired t test.
In the present study mean levels of middle forced expiratory volume (FEV25-75%) in non smoker traffic policemen group (3.73 ± 0.01) was lower than non smoker control group (4.18 ± 0.04). This difference was statistically significant (P < 0.0001) when compared by using an unpaired t test. Mean levels of middle forced expiratory volume (FEV25-75%) in Smoker traffic policemen group (3.27 ± 0.07) was also found lower than Smoker Control group (3.27 ± 0.07) and the difference was statistically significant (P < 0.0001) when compared by using unpaired t test.
In the present study mean levels of peak expiratory flow rate (PEFR) in non smoker traffic policemen group (358.44 ± 6.81) was lower than non smoker control group (420.9 ± 4.93). This difference was statistically significant (P < 0.0001) when compared by using an unpaired t test. Mean levels of PEFR in smoker traffic policemen group (279.13 ± 3.49) was also found lower than smokerscontrol group (416.7 ± 5.62) and the difference was statistically significant (P < 0.0001) when compared by using unpaired t test.
| Discussion|| |
Traffic police personnel have shown significantly declined FVC, FEV 1, SVC, and MVV when compared with predictive normal values, which is probably due to exposure to vehicular exhaust. Comparison of test values between groups showed significantly reduced FVC, MVV, and increased FEV1/FVC ratio and insignificantly declined FEV1 and SVC in cases as compared to controls. Traffic personnel with a longer duration of exposure showed significantly reduced lung functions than those with shorter duration. Smokers showed lower test values as compared to non-smokers with significance only in the unexposed group.
Exposure to air pollutants is known to be harmful to health and in particular to the lungs. Traffic police personnel, due to the nature of their job are at particular risk as they are continuously exposed to emissions from vehicles. These personnels have to undergo physical strain in an environment polluted by fumes, the exhaust of vehicles, use of blowing horns, blow of dust in the air by a speeding vehicle, etc. Prolonged exposure to dust can cause bronchial problems. The presence of various particles and gases from vehicular emission like carbon dioxide, carbon monoxide, sulfur, benzene, lead, nitrogen dioxide, nitric oxide and black smoke etc., play a role in the pathogenesis of respiratory diseases. Acute effects include irritation of the eyes and nose, lung function changes, headache, fatigue, and nausea. Chronic exposure is associated with cough, sputum production, and reduction in lung function. In the long run, the pollutants produce diseases like asthma, COPD, and malignancy in the exposed individuals apart from significant changes in lung functions. Pulmonary function tests parameters showed a reduction in respiratory function of traffic policemen. Significant differences were observed between observed and expected values, which highlight the health hazards of occupational exposure. This fact is strengthened by the high prevalence of obstructive disease in this population. Similar observations have been observed in studies in India and other countries as well. The increase in the prevalence of respiratory symptoms among other occupation like taxi drivers, auto-rickshaw drivers have been reported in some studies. Reduction in PEFR values indicates the risk of obstructive airway disease in this occupational group who are exposed to air pollutants every day.,
This decline in lung function parameters may be due to a large number of pollutants such as sulfur dioxide, carbon monoxide, nitric oxide, particulate matter, and ozone influence on the body. These pollutants put a burden on the lungs and the resulting oxidative stress is thought to contribute to the genesis of fibrotic lung diseases, chronic bronchitis, emphysema, and lung cancer. Toxic chemicals and gases of vehicular emission produce irritation and allergy in the lungs and airways of subjects who are exposed to them for a long time, like the subjects of our study, traffic policemen.
Vehicular exhaust particularly organic extracts of diesel exhaust induce reactive oxygen species in macrophages and bronchial epithelial cells which are key cell types targeted by the particulate matter in the lung. Particulate matters are ultrafine particles that get deposited on alveolar walls and in the nuclei of the cells by diffusion and retained in lung parenchyma. These small sized particles are responsible for oxidative stress and mitochondrial damage probably because of their small size and larger surface-to-volume ratio ability to penetrate into the cell interior and localize near mitochondria. The oxidative stress mediated by particles may arise from the direct generation of reactive oxygen species (ROS) from the surface of the particles or form of soluble compounds carried by these particles such as polyaromatic hydrocarbons. Oxidative stress might up-regulate redox sensitive transcription factor via nuclear factor kappa-B in airway epithelial cells thus increasing the synthesis of pro-inflammatory cytokines and resulting in cell and tissue injury of lung parenchyma and airway.
Along with the effect of pollution, cigarette smoke modifies type IV collagen and also leads to lipid pre-oxidation, and that increased macrophage adhesion and activation within airway lumina are stimulated by the modification of collagen IV. This is an important step in the initiation of the inflammatory and destructive process which ultimately leads to the development of obstructive lung disease like emphysema. The smoke-induced inhibition of ciliary beat frequency of the ciliated columnar airway epithelium is associated with recurrent episodes of bronchitis and lower respiratory tract infections. The exhaust of the vehicles produces organic extracts of particles which induces ROS in the macrophages and bronchial epithelial cells in the lungs. This ROS activates the promoters of cytokines and chemokines involved in allergic inflammation through activator protein 1 and nuclear factor kB signalling pathways. It also induces apoptosis and necrosis in bronchial epithelial cells via the mitochondrial pathway. Also, most of the immune responses responsible for allergic inflammation are due to enhanced production of immunoglobulin E due to polyaromatic hydrocarbons in vehicular emissions.
Pre-placement examinations like in other industries would help individuals to choose the right job and reduce the risk of getting ill. Periodic examination of traffic policemen will help in identifying the health problems. Emphasis has to be put on preventive aspects rather than on diagnosis and management of respiratory diseases. Hence protective mask-wearing and reduction timing of work shifts will help in reducing the exposure to air pollutants.
| Conclusion|| |
Significant reduction in all the parameters in traffic policemen compared to the Control group proves that preventive measures like pollution masks, Regular breathing exercises, etc., have to be implemented at the workplace to reduce health hazards of continuous exposure to traffic dust.
| Limitations of the Study|| |
Detailed information on air pollutants in the study area would have helped to understand the issue better. The additional effect of smoking on PFT parameters should have been added to improve the knowledge. Though 60% of the traffic policemen were exposed for less than three years duration, the high level of obstructive respiratory disease in traffic policemen might indicate a higher density of air pollutants. Assessment of respiratory status by spirometry along with clinical history and examination by chest physicians would have added strength to the study.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2]