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 Table of Contents  
Year : 2021  |  Volume : 6  |  Issue : 1  |  Page : 35-42

Evaluation of impact of ambient air pollution on respiratory health of traffic police in Kolkata

1 Department of Physiology, Environmental and Occupational Physiology Laboratory, Sister Nibedita Government General Degree College for Girls, Kolkata, West Bengal; Department of Physiology, Ergonomics and Occupational Physiology Laboratory, University of Kalyani, Kalyani, India
2 Department of Economics, Eco-Stat Laboratory, Sister Nibedita Government General Degree College for Girls, Kolkata, West Bengal, India
3 Department of Physiology, Ergonomics and Occupational Physiology Laboratory, University of Kalyani, Kalyani, West Bengal, India
4 Department of Physiology, Environmental and Occupational Physiology Laboratory, Sister Nibedita Government General Degree College for Girls, Kolkata, West Bengal, India

Date of Submission17-Jun-2020
Date of Decision27-Jun-2020
Date of Acceptance17-Jul-2020
Date of Web Publication08-Apr-2021

Correspondence Address:
Dr. Atanu Saha
Department of Physiology, Environmental and Occupational Physiology Laboratory, Sister Nibedita Government General Degree College for Girls, 20B, Judges Court Road, Alipore, Kolkata 00 027, West Bengal
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/bjhs.bjhs_58_20

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BACKGROUND: Air pollution is associated with a broad spectrum of an environmental health problem, caused by increased urbanization and population, globally. Emission of pollutants was strongly implicated in acute morbidity and mortality associated with severe pollution. Traffic cops are most vulnerable due to the nature of their job, continuously exposed to toxic pollutants.
AIM OF STUDY: The study aimed to assess the physical and respiratory morbidities of traffic cops due to the effect of environmental pollutants.
METHODOLOGY: Air quality data were collected by the Central Pollution Control Board. Traffic cops were selected from three traffic zones of the city. Anthropometric data were collected by anthropometric instruments. Health assessment was performed via the questionnaire method. Pulmonary function parameters were recorded via digital spirometer.
STATISTICAL ANALYSIS: Collected data were analyzed statistically via SPSS (V-16.0).
RESULTS: Particulate matter 2.5 (PM 2.5) and PM 10 found to be dominant pollutants in three zones of Kolkata. Air Quality Index values are high in winter. Any type of respiratory symptom is highest in the north, followed by the south and central zones. In the central zone, forced expiratory volume in 1 second and forced expiratory flow from 25% to 75% values significantly changed with work exposure. The habit of smoking also showed a significant effect on pulmonary function test (PFT) parameters. The difference of the change in PFT among the three zones was found significant.
CONCLUSION: The result of the study indicates that outdoor environmental exposure creates detrimental effects on lung function parameters of traffic cops among the three zones of Kolkata. Use of mask, healthy food intake, performing exercise, and regular medical check are suggested to prevent respiratory damages of police personnel.

Keywords: Air pollutants, particulate matters, police personnel, pulmonary function parameters

How to cite this article:
Dey A, Mishra T, Sahu S, Saha A. Evaluation of impact of ambient air pollution on respiratory health of traffic police in Kolkata. BLDE Univ J Health Sci 2021;6:35-42

How to cite this URL:
Dey A, Mishra T, Sahu S, Saha A. Evaluation of impact of ambient air pollution on respiratory health of traffic police in Kolkata. BLDE Univ J Health Sci [serial online] 2021 [cited 2023 Jun 3];6:35-42. Available from: https://www.bldeujournalhs.in/text.asp?2021/6/1/35/313357

Air pollution is considered as one of the grave issues that are more prevalent in most industrial towns and cosmopolitan cities of the world.[1] Problems caused by different atmospheric pollutants are originated mainly from vehicular emissions, smokes from different industries, and power plants. The most common route of entrance of pollutants in human is the respiratory passage, causing lung diseases such as asthma, bronchitis, emphysema, and chronic obstructive respiratory disease. Occupational lung disease rates as one of the most common work-related illnesses and therefore an issue of great priority in the industrialized countries and also increasingly in the developing countries.[2] Residential proximity to a busy road is associated with different respiratory health symptoms and asthmatic exacerbation.[3],[4] Job of police is one of the most unpredictable and most challenging among all occupations. Their occupational design, leave status, salary system, arms, and ammunitions are not in the standard system and duty rotation shifts are irregular and disorganized.[5],[6] They face different kinds of stressors during their duty period which make them suffer from different types of physiological and psychological problems.[7]

Background of the study

People participating in different outdoor occupations are exposed to noisy and polluted environment. Traffic cops are continuously being exposed to vehicular emissions and other toxic air pollutants, causing an increased risk of respiratory and cardiovascular diseases.[8] These observed impacts pose serious health and safety culture in the workplace.[9] Carbon dioxide, carbon monoxide, oxides of sulfur and nitrogen (SO2 and NO2), ozone, ammonia (NH3), and different sizes of particulate matters (PM 2.5 and PM 10) are included as hazardous pollutants, as well as, vehicular fumes contain dangerous chemicals such as toluene, benzene, and xylene, which are being classified as both carcinogenic and xenotoxic.[10],[11] Published research papers on traffic cops reported different occupational health issues due to occupational exposure. Follow-up studies for a long time in polluted cities showed an increased prevalence of upper respiratory symptoms in traffic personnel.[12] Police personnel, who is not using masks, is found to have a higher risk of abnormal forced expiratory volume in 1 second (FEV1) than who is using them. Police personnel found to be suffered due to cough or phlegm and rhinitis symptoms more than civilians due to exposure in air pollution.[13] Pulmonary function tests (PFTs) were performed by Vitalograph or by the digital spirometer. It is found that traffic police constables are at a higher risk group in the population which is likely to develop respiratory dysfunctions.[14] Significant variation was found in Peak Expiratory Flow Rate (PEFR), Forced Expiratory Volume in 1st second (FEV1), and Forced Vital Capacity volumes of the Traffic Policemen against the control group in terms of exposure.[15] Similar studies, but with improved methods, were performed where no consistent trend of decreased pulmonary function was found in them.[16] Among various air pollutants, PM 2.5 and PM 10 are found to be associated with decreasing conditions of respiratory and cardiovascular health of traffic police, leading to the risk of death.[17],[18] The survey among a large number of traffic policemen also showed that exposed traffic policemen have a major prevalence of respiratory symptoms and allergic sensitization than nonexposed policemen, which shows ill effect of pollutants on respiratory health on them.[19] Restriction of lung expansion, obstruction, and narrowing of the airways was also found to be a major problem among them. Smokers were found to be worse in respiratory health conditions.[20] Ambient air pollution is an important risk factor in the evolution of chronic obstructive pulmonary diseases (COPD). Asia is found to be a center of increase in patients with COPD with traffic pollution that is one of the most important factors.[21] Research has shown that healthy and safe work environments facilitate good working relationships.[22] In addition, a good occupational health system management can enhance efforts in fighting escalating crime rates.[23]

Few studies have been attempted to find the effect of pollutants on respiratory health and future remedies for traffic police personnel. Hence, the objectives of this study are to measure ambient air quality data of different locations of Kolkata through environmental monitoring, identification and screening of traffic cops of different traffic zones, and assessment of general physiological and respiratory health parameters of traffic cops in different zones of Kolkata.

  Methodology Top

Study design

This study was designed to investigate the respiratory morbidity due to exposure in air pollutants. Ambient air quality data were collected from the Central Pollution Control Board in the form of the air quality index (AQI).[24] Participants were being selected from different traffic guards of Kolkata. The city traffic zones were categorized into three different zones, north, central, and south accordingly.

Study population

A total number of 300 participants were selected from different traffic zones, among which 228 participants were found to be fit for our study requirement. Participants were selected according to the inclusion criteria by stratified random sampling. They were interviewed with a set of questionnaires to collect information about general health, demographics, and the occurrence of respiratory symptoms. One hundred thirty-eight number of participants participated in PFTs. Participants were categorized as samples of three different zones.

Inclusion and exclusion criteria

Participants were selected from age groups of 20 years to 50 years and with a minimum of 2 years of work experience in this field. Participants with surgical operations in respiratory organs and under medication due to respiratory distress were excluded from this study. Traffic cops who did not perform any kind of on-road duty for 3 years were selected as controls.

Ethical consideration

Ethical approval for this study was obtained from Sister Nibedita Government General Degree College for Girls Research Ethics Committee.

Estimation of parameters

  • Anthropometric measurements were collected by the weighing machine and Martin's anthropometer. Body mass index (BMI) was calculated by weight in kg/height2 in meter
  • Respiratory health conditions were assessed by the Modified European Community Respiratory Health Survey-II questionnaire.

Lung function parameters of all the participants were measured via PFT using a computerized spirometer consistent with American Thoracic Society/European Respiratory Society guidelines for Spirometry (2005). The parameters which were measured using the spirometer included FVC, FEV1, FEV1/FVC ratio, forced expiratory flow from 25% to 75% (FEF25-75), and PEFR.

Statistical analysis

Statistical analysis of data was performed using SPSS (V-16.0). The variables are expressed as a mean ± standard deviation.

  Results Top

[Table 1] represents the values of AQI and further health concerns due to ill effects on the human body. Values found to be satisfactory to moderate in the first two trimesters, but AQI values increased in the second two trimesters. PM 2.5 and PM 10 were found among the most dominant pollutants in the environment.
Table 1: Tabular representation of air quality index values of three zones of Kolkata (Central Pollution Control Board)

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[Figure 1] represents the ambient air quality data of three different zones of Kolkata in the form of AQI. The duration of recording this data is from March 2019 to February 2020. AQI value found to be increased in the winter season and decreases in the summer season.[Table 2] shows selected sociodemographic characteristics of the participants. Age, body height, weight, and work experience values were collected. BMI was calculated by weight in kg/height2 in meter.
Figure 1: Graphical representation of air quality index values of selected zones of Kolkata

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Table 2: Sociodemographic details of traffic police personnel

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[Figure 2] represents different respiratory health problems of traffic police personnel. Data are represented as percentage values. The most prevalent symptom is found wheeze and tightness in both exposed and control groups, followed by cough and phlegm in the chest, shortness of breath, attack of cough, trouble in breathing and cough in winter, dust allergy, and asthma.
Figure 2: Graphical representation of respiratory health problems of traffic police personnel

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The next bar diagram represents the percentage distribution of zone-wise prevalence of any health-related problems. The formula used for calculating the problems are as follows: prevalence of any respiratory syndrome: yes = 1 if the subject reported for 1/7* (wheeze tightness + shortness of breath + cough phlegm in chest + attack of cough + cough in winter + trouble in breathing + asthma) >0, No = 0, otherwise.

Prevalence of any digestive syndrome : yes = 1 if the subject reported for 1/7* (constipation + loose_motion + indigestion + diarrhea + appetite loss + stomachache + gastritis) >0, No = 0, otherwise.

Prevalence of any eye problem: yes = 1 if the subject reported for 1/4* (myopia + hypermetropia + redness in eye + watering in eye) >0, No = 0, otherwise.

[Figure 3] represents the bar diagram of any respiratory, digestive, and eye problems found in three zones of traffic police personnel. Occurrence of respiratory problem was found to be higher in north zone compared to central and south. Eye problems were found to be most prevalent in the central zone, followed by south and central zones. Digestive problems were found most prevalent in south, central, and north zones, respectively.
Figure 3: Graphical representation of physiological problems of traffic police personnel

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Case study I

Area-wise mean comparison test of pulmonary function parameters is performed among the exposed group on the basis of years of experience in traffic police service. For this purpose, the following formula has been used. PFT values are represented in tables as:

FEV1 (%) = (Pre FEV1/Pred. FEV1] × 100)

FVC (%) = (Pre FVC/Pred. FVC] × 100)

FEV1/FVC (%) = ([Pre FEV1/FVC]/[Pred. FEV1/Pred. FEV1] × 100)

FEF25-75 (%) = (Pre FEF25-75/Pred. FEF25-75] × 100)

PEFR (%) = (Pre PEFR/Pred. PEFR] × 100)

[Table 3.1] shows that the mean of the two groups is divided on the basis of work experience in traffic police service, altered significantly at 1% level with the change in experience span for FEV1%, and in case of FEF25-75 (%), the mean comparison test is significant at 10% level of significance, whereas other parameter variations are not significant. Thus, the duration of work experience significantly affected FEV1% and FEF25-75 (%) in Central Kolkata.

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In [Table 3.2], the values of lung function parameters did not alter significantly. The number of variation of subjects or sampling may be a reason for this result.

From the [Table 3.3], no significant change is observed in PFT parameters with the change in work exposure in the south zone of Kolkata. The number of variations of subjects or sampling may be a reason for this result.

Case study II

In this case study, the analysis of area-wise mean comparison test of PFT parameters among the exposed group is performed on the basis of smoking status of traffic police personnel.

In case study 2, impact of smoking was compared with pulmonary function values. In [Table 4.1], the mean comparison test is found to be statistically significant at the 5% level of significance for FEV1/FVC (%) with smoking status of traffic police in Central Kolkata.

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[Table 4.2] represents the comparison of PFT parameters with smoking status of police personnel. The mean comparison test is found to be statistically significant for FVC (%) and PEFR (%) with a smoking status of traffic police working in the north zone at 5% and 10% level of significance, respectively.

[Table 4.3] represents the comparison of PFT parameters with smoking status of police personnel working in the south zone of Kolkata. The mean comparison test in case of FVC (%) and (FEV1/FVC) (%) values is significant at the 1% level with smoking status in south zone, whereas it is found significant at a 10% level for FEV1 (%).

As shown in [Table 5], analysis of the difference of PFT parameters of traffic police is performed in three different zones on the basis of analysis of variance.
Table 5: One-way ANOVA test pulmonary function parameters among three different zones of traffic police personnel

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[Table 5] represents the variation of lung function parameters with respect to change in three different zones. The analysis implicates that the variation in case of PEFR% is significant at 5% level of significance with the respective changes in zones of exposure of traffic police personnel, though FEV1(%), FVC(%) and FEF25-75(%) values did not show any significant change in pulmonary function parameters of traffic cops in respect to different zones of Kolkata.

  Discussion Top

Data obtained from three different zones of traffic cops of Kolkata were analyzed to find the significance. [Table 1] and [Figure 1] represent air quality data of north, central, and south zones of Kolkata. From the obtained results, it was found that AQI values were found to be much higher in the winter season than in the summer season. AQI values start to increase in the month of September, peaks in January, and decreases in March. North zone has a much higher index in the first two trimesters, whereas the central zone marked as more polluted in the last two trimesters. Most dominant pollutants were found PM 2.5 and PM 10. PM 2.5 is tiny particles of 2.5 μm s and PM 10 has particles of <10 μm particles or droplets in the air. PM 2.5 able to travel deeply into the respiratory tract, reaching the lungs. These particles can cause health problems such as the eye, nose, throat, and lung irritations, coughing, runny nose, and shortness of breath. In worse conditions, it can cause medical conditions such as asthma and heart disease. Car, truck, and other vehicles burning of fuels such as wood, heating oil, or coals are the main sources of these PM. To prevent the damage caused by these pollutants, personal protective equipment like a respirator, N-95, and N-99 mask are useful. They prevent the entry of PMs in respiratory organs. [Figure 2] represents the respiratory problem caused due to these pollutants. Among the three zones problems, respiratory problems found highest in the north. Controls also faced respiratory problems such as the exposed group, which might indicate the pollutants also affecting them in indoor working conditions. The prevalence of any type of respiratory symptoms is found highest in the north, followed by south and central zones. Any type of digestive problems was found most in the south, followed by central and north zones. Eye problems are highest at central, followed by south and north zones.

PFT is an important tool to find out patients with respiratory pathology. They provide important information relating to the large and small airways, the pulmonary parenchyma, and the size and integrity of the pulmonary capillary bed. They do not provide a diagnosis, but they help to diagnose different patterns of abnormalities in various respiratory diseases. PFT parameters describe abnormal results and correlate these with underlying pathology.[25]

Spirometry and the calculation of FEV1/FVC % allow the identification of obstructive or restrictive ventilatory defects. A FEV1/FVC <70% where FEV1 is reduced more than the FVC signifies obstructive defects such as COPD and asthma. The FEV1/FVC >70% where FVC is reduced more than FEV1 is seen in restrictive defects such as interstitial lung diseases. The maximal flow rate during expiration can also be measured as PEFR. The maximal flow rates between 25% and 75% of the vital capacity FEF25-75(%) can be measured which provides important information regarding small airway function.[25],[26]

Duration of exposure in working conditions is an important factor in the case of examining subjects. Traffic cops were categorized into two groups to find out if there is any significant effect on lung parameters. In the central zone, FEV1(%) and FEF25-75(%) values changed significantly with respect to the length of working experience. The long duration of exposure worsens the lung condition, causing a reduction in pulmonary capacity and restriction in small airways.

Values of pulmonary parameters were compared with the smoking status of the subjects. It was found that means of FEV1/FVC% significantly decreased in case of ever smokers with respect to nonsmokers in the central zone. FVC% and PEFR% mean values decreased significantly in the north and FEV1%, FVC%, and FEV1/FVC% mean values decreased in the south traffic zone. Reduction in FVC value could be due to obstructive or restrictive lung disease. Reduced FEV1 values indicate early symptoms of COPD. Lower FEV1/FVC ratio indicates that something is blocking lung airway passages. PIFR indicates the maximum capacity of the lung to exhale.

[Table 5] represents the statistical significance of pulmonary function parameters of these zones, whether they are significantly different from others or not. It was found that PEFR values significantly differed from each zone to others. PEFR value is an important part of managing asthma symptoms and prevention of asthma attacks.

  Conclusion Top

Traffic police personnel are occupationally exposed to environmental air pollutants which crate adverse health effects on the respiratory system of traffic police personnel. PM 2.5 and PM 10 are highest found pollutants in Kolkata. Individuals with reduced lung function values may suffer respiratory health problems. Long duration of exposure, duty zone with higher pollutants, and habit of smoking worsen the conditions. For a long time, deterioration of lung function makes them more venerable for respiratory diseases like COVID19.


Some recommendation is suggested to avoid or reduce the damages due to air pollution:

  1. Use of personnel protective equipment such as masks and respirators will prevent the entry of pollutants such as PMs in respiratory organs. N-95 and N-99 mask are especially useful in this matter
  2. A regular health food intake will reduce the damage caused by pollutants in the body. Intake of Vitamin C rich foods helps to detoxify reactive oxygen species and reduce further damage at molecular level
  3. Habit of regular physical exercise and yoga helps in betterment of physical, as well as respiratory health of human body
  4. Physical checkup at a regular basis is much needed for traffic cops, as they are always vulnerable to open environment. Early diagnosis of any symptoms will help to cure fast in all circumstances.


We sincerely thank to The Deputy Commissioner of Police, Traffic, Kolkata Police, for allowing us to perform the study and Sister Nibedita Government General Degree College for Girls, for providing proper laboratory facility for this study.

Financial support and sponsorship

Financial Support provided by Department of Science and Technology and Biotechnology, Government of West Bengal.

Conflicts of interest

There are no conflicts of interest.

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  [Figure 1], [Figure 2], [Figure 3]

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]

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