Abstract
Background
In India, it was reported previously about varying prevalence of asthma and chronic bronchitis among leather tannery workers with moderate to high exposures at the workplace to be significantly associated with asthma. This study intended to estimate the prevalence of asthma, tuberculosis, and chronic bronchitis among leather tannery workers and to identify the risk factors associated with it.
Data and Methods
The data used in this study were collected through a cross-sectional household survey of 284 male tannery workers in the Jajmau area of Kanpur city in the state of Uttar Pradesh, during January–June 2015. A binary logistic regression analysis was performed to identify the factors associated with respiratory symptoms.
Results
The prevalence Asthma and Chronic Bronchitis among Tannery workers was 12.3% and 11.6% which is higher as compared to non-tannery workers. The findings revealed that the prevalence of symptoms suggestive of asthma, tuberculosis, and chronic bronchitis among the tannery workers was higher compared to non-tannery workers. The study revealed that long time tannery working harms health, as tannery workers are more likely to be suffering from asthma and chronic bronchitis who worked above 11 years in the tannery (p < 0.62).
Conclusion
The study concludes that age, education, media exposure, working hours in the tannery, type of work engagement within tannery occupation, and exposure to chemicals are the major risk factors for asthma, tuberculosis, and chronic bronchitis among the male tannery workers. Specific health insurance facilities should be provided, such as the Employee's State Insurance Scheme (ESIS), from the day a person begins work in a tannery.
Keywords
1. Introduction
The leather industry occupies a place of eminence in the Indian economy because of its massive potential for employment, growth, and exports. The industry has received criticism on environmental grounds, and the tanning industry viewed to be a major source of water pollution.
1
Tannery occupation is known for the pollutant, having health risks at the workplace. Due to this, the working environment plays important health risk factors among tannery workers. Working in tanneries exposed tannery workers to physical, chemical, and biological agents as well environment, which makes them vulnerable to several toxic chemicals, which are hazardous for health and might lead to an increase in morbidity and mortality.2
The chemical hazards in tanneries include vegetal tannins, chromium salts, and biocides, bleaching agents, hydrogen sulphide, and dyes. Infection with anthrax is common.3
The hazards may cause minor illnesses, or they may lead to severe chronic debilitating diseases.3
Dust produced by various processes such as by buffing and shaving and this dust can affect the respiratory tract, which may lead to the most common respiratory problem of chronic bronchitis among the tannery workers.
2
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Similarly, Chromium produced in tanneries has the potential to bind with skin proteins of tannery workers to produce complex antigens, which lead to hypersensitivity. The resulting contact dermatitis could be a preliminary condition to the development of bronchial asthma.4
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Chromium dust may enter the body by inhalation, ingestion, and by direct cutaneous contact. Exposure to Chromium increases the risk of dermatitis, ulcers, and perforation of the nasal septum and respiratory illnesses along with increased lung and nasal cancers.6
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, 10
, 11
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Chromium-specific health hazards like carcinoma of the larynx and lung parenchyma and paranasal sinuses have also been reported.12
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A study conducted by Rastogi (2008) reveals that the prevalence of respiratory disease symptoms was found to be significantly higher than that reported by the control group (16.7% vs. 4.3%) (P < 0.001)13. Issever (2007) reported that after the basic physical examination, respiratory functions were measured by spirometer and the workers questioned about asthma. Health problems included gastrointestinal complaints (7.30%), bronchitis (3.11%) and asthma (3.0%).
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A study was done by Shahzad (2006) also reveals the prevalence of actual asthma was 10.8%, and perceived work-related asthma was 5.3% in the study population of tannery workers.5
Tannery workers who perceived to have allergy were more likely to have asthma if their duration of work was eight years adjusted OR = 2.3 at 95%, and this relationship was even stronger if the duration was 13 years adjusted OR = 3.7.There are very limited studies of the health effects of chronic exposure to chromium in leather tanning among developing countries. In India, it was reported previously
5
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about varying prevalence of asthma among leather tannery workers with moderate to high exposures at the workplace to be significantly associated with asthma.26
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There is a further need to study prevalence and risk factors of Asthma, Tuberculosis, and Chronic bronchitis in tannery workers to better account for Asthma burden and to identify high-risk exposures in a factory environment for prevention purposes. This study intended to estimate the prevalence of asthma, tuberculosis, and chronic bronchitis among leather tannery workers and to identify the risk factors associated with it in Kanpur city, India.2. Data and methods
2.1 Data
This cross sectional household study was conducted during the period January–June 2015 among male tannery and non-tannery workers in the Jajmau area of Kanpur City in the state of Uttar Pradesh, India. The area Jajmau suburb is located in an area south-east of the Kanpur city, which is close to the military cantonment area, and on the southern bank of the river Ganga. Since the British regime, Kanpur has emerged as a major leather-processing region in Uttar Pradesh in North India. Kanpur has a total GDP (PPP) of 22 billion US$, and it ranks as 9th among the top ten Industrial cities in India. Kanpur has traditionally been an industrial city and a major economic center in Uttar Pradesh. Currently, there are 402 registered leather tanneries, which are located in the eastern part of the city, with an estimated 20,000 tannery workers.
13
More than 20,000 people were working in the leather industry, and among them, a substantial proportion of tannery workers was living in the Jajmau Area. From the major concentrations of the tannery industry in and around Kanpur, Jajmau was selected for the study, which is the industrial suburb of Kanpur city. It is known as Leather City as it contains some of the largest and finest tanneries in India. This study was focused on leather tannery workers, i.e., those who were engaged in tanning work in the leather industry.2.2 Sampling design
This study has adopted a three-stage sampling design. At the first stage, seven localities in the Jajmau area, namely Tadbagiya, Kailash Nagar, J.K. colony, Asharfabad, Motinagar, Chabeelepurwa, and Budhiyaghat, were selected based on a higher concentration of leather tannery worker's population in these areas as reported by various stakeholders in the city. In the second stage, three out of the seven localities, namely Budhiyaghat, Tadbagiya, and Asharfabad, were chosen by using probability proportional to size (PPS) sampling technique after arranging them in ascending order of estimated number of Households (HHs) of leather tannery workers. Subsequently, a comprehensive household listing and mapping were completed in each of the three localities, and all the household were classified into three groups-households having at least one tannery worker, irrespective of having or not having any non-tannery worker, households having non-tannery worker (s) and households having no worker. The first two groups of households constituted two independent sampling frame in each of the three selected localities. However, the third group of households was excluded from the study. Once the updated and comprehensive sampling frames were developed in each of the three localities included in the study, a circular systematic random sampling was used for selection of households at the third and the last stage. In case, if more than one worker were in a household, the target respondent was selected using KISH table (Kish 1949). In each of the three selected areas, 100 households were selected for each of the two categories i.e., a tannery as well as non-tannery workers, using a circular systematic random sampling procedure. Thus, a total of 600 HHs were selected for the interview, and a total of 284 HHs having at least tannery workers and 289 HHs of non-tannery worker(s) were interviewed successively.
2.3 Participants and occupational categories
The study comprised 284 male tannery and 289 non-tannery workers of age group 18–70 years from Jajmau in suburban Kanpur. We have inquired about the occupation of the respondent and classified them into two categories that is tannery and non-tannery workers.
2.4 Ethical consent
The study is a part of PhD thesis research work of the first author; we have received the ethical clearance from the Student Research Ethics Committee of International Institute for Population Sciences Mumbai, India. We have also obtained consent to participate from each of the respondents before starting the interview.
2.5 IRB approval
Ethical review board of International Institute for population Sciences, Mumbai have approved the present study.
3. Methods
3.1 Dependent variables
Asthma was diagnosed if the respondent informed the symptoms “Had wheezing or whistling in your chest at least three months in the last year. Tuberculosis was diagnosed by asking how frequently they have experienced the following symptoms cough (usually with mucus), coughing up blood, excessive sweating, especially at night, fatigue, fever, weight loss. The symptoms diagnosed Chronic Bronchitis (CB) “Did you cough up phlegm most days or nights for at least three months in the previous year.”
3.2 Independent variables
Age in years, education, marital status, marital status, caste, media exposure, the standard of living index, type of job contract, type of work engagement of tannery workers, type of work engagement of non-tannery workers, work experience in the current tannery, work experience in the previous tannery, average working hours in a day, average working days in a week, chemicals in the air and airborne dust.
3.3 Statistical analysis
Univariate, bivariate, chi-square test, and logistics regression analysis have been used. The logistic regression, more commonly called logit regression, is used when the response variable is dichotomous (i.e., binary or 0–1). This model has an advantage over the simple linear regression model partly because it is easy to interpret the result as it leads to a logit model that derives the relative likelihood of the occurrence of the event of interests.
4. Results
4.1 Demographic and socio-economic characteristics of tannery and non-tannery workers
Table 1 presents the percentage distribution of various socio-economic and demographic characteristics of tannery and non-tannery workers. The overall sample of tannery workers and non-tannery workers was 284 and 289, respectively. More than half (54%) of the tannery workers and over three-fifths (63%) of non-tannery workers were aged 36 years and above. Majority of the tannery (66%) and non-tannery workers (62%) were illiterate. Majority of the tannery and non-tannery workers (85%–90%) are currently married. About two-thirds of tannery workers (66%) are Muslim, and the remaining are Hindus. Two-thirds of the tannery workers (66%) belong to the schedule castes, 18% from other backward castes, and 16% belong to other caste groups. More than two-fifths of tannery and non-tannery workers had medium levels of media exposure. This study used the standard of living index, is categorized into three categories low, medium, and high, and its proportions are 38%, 31%, and 31% for tannery workers, respectively. For non-tannery workers, these proportions are 29%, 36%, and 35%, respectively.
Table 1Percent distribution of tannery and non-tannery workers by some selected background characteristics in Kanpur, India, 2015.
| Background Characteristics | Tannery | Number | Non-tannery | Number |
|---|---|---|---|---|
| (%) | (N) | (%) | (N) | |
| Age in years | ||||
| 16–24 | 10.2 | 29 | 6.9 | 21 |
| 25–35 | 36.3 | 103 | 29.8 | 85 |
| 36+ | 53.5 | 152 | 63.3 | 183 |
| Education | ||||
| Illiterate | 66.1 | 188 | 62.2 | 179 |
| Up to primary | 13.4 | 38 | 9.0 | 26 |
| Middle school | 8.8 | 25 | 8.7 | 26 |
| High school & above | 11.7 | 33 | 20.1 | 58 |
| Marital Status | ||||
| Currently married | 85.5 | 243 | 89.9 | 260 |
| Never married | 9.4 | 27 | 6.3 | 18 |
| Widowed/Widower | 5.1 | 14 | 3.8 | 11 |
| Religion | ||||
| Hindu | 33.8 | 96 | 40.8 | 118 |
| Muslim | 66.2 | 188 | 59.2 | 171 |
| Caste | ||||
| Schedule caste | 65.5 | 186 | 36.3 | 61 |
| Other backward class | 18.3 | 52 | 34.3 | 122 |
| Others | 16.2 | 46 | 29.4 | 106 |
| Media exposure | ||||
| Low | 22.9 | 65 | 21.1 | 85 |
| Medium | 48.6 | 138 | 42.2 | 104 |
| High | 28.5 | 81 | 36.7 | 100 |
| Standard of living index | ||||
| Low | 37.7 | 107 | 29.2 | 85 |
| Medium | 31.3 | 89 | 36.1 | 104 |
| High | 31.0 | 88 | 34.7 | 100 |
| Total | 100 | 284 | 100 | 289 |
Note: Standard of living index includes: electricity, bed, chair, table, cot, pressure cooker, sewing machine, LPG gas, mobile phone, water pump, electric fan, color TV, mixer grinder, refrigerator, radio, watch, cycle, motorcycle. # Mean and confidence interval, NA: Not available. Media exposure includes: Newspaper, magazine, movies, T.V., radio and internet.
4.2 Work related characteristics of tannery and non-tannery workers
The work-related characteristics of tannery and non-tannery workers have been presented in Table 2. The average age of male tannery workers was 38 years (SD = 1.4). The vast majority of male tannery workers (89%) are working on temporary job contracts, and the rest (11%) are engaged in this occupation on a permanent basis. The respondents work in various tannery processes. A little over 8% are involved in beam housework, 24% in wet finishing, 50% in dry finishing, and 17% in miscellaneous kinds of work. In addition to that, non-tannery workers worked in numerous job categories that are broadly classified into six domains. Around 12% of the non-tannery workers engage in industrial work, 27% in manual work, 20% in construction work, 10% in clerical work, 25% have own business and shop, and 7% in other job categories. The mean duration of their job was 10 (SD = 0.9) years. The average work experience of male tannery workers was 18 years. The male tannery workers also reported that they work almost every day of the week with a 9-h working day as the norm. On average, they worked 6.5 days (SD = 0.6) a week and 9.5 h (SD = 0.2) a day that is the violation of labour law according to the factory act in India.
Table 2Work related characteristics of tannery workers in Kanpur, India, 2015.
| Variables | (%) | (N) |
|---|---|---|
| Age in years (Mean ± SD) | 38.5 ± 1.4 | 284 |
| Type of Job contract | ||
| Temporary job (daily wages) | 89.1 | 252 |
| Permanent job | 10.8 | 32 |
| Type of work engagement of tannery workers | ||
| Beam house work | 8.4 | 24 |
| Wet finishing work | 24.2 | 69 |
| Dry finishing work | 50.5 | 142 |
| Miscellaneous work | 16.8 | 49 |
| Type of work engagement of non-tannery workers | ||
| Industrial work | 11.7 | 34 |
| Manual work | 26.5 | 76 |
| Construction work | 20.0 | 76 |
| Clerical work | 10.0 | 24 |
| Business & shop | 24.5 | 71 |
| Others | 7.0 | 21 |
| Work experience in current tannery (Mean ± SD) | 10.1 ± 0.9 | 284 |
| Work experience in previous tannery (Mean ± SD) | 7.9 ± 1.3 | 99 |
| Average working hours in day(Mean ± SD) | 9.5 ± 0.2 | 284 |
| Average working days in a week(Mean ± SD) | 6.5 ± 0.1 | 284 |
4.3 Prevalence of symptoms suggestive of respiratory problems among tannery and non-tannery workers
The prevalence of symptoms suggestive of Asthma among tannery as well as non-tannery workers is shown in Table 3. It is observed that tannery workers are at a higher risk of developing symptoms suggestive of Asthma. For instance, wheezing (or whistling sounds in the chest) was higher among tannery workers (12%) than in non-tannery workers (8.7%). Similarly, 6.3% of tannery workers reported that we wake up with a feeling of breathlessness, while only 3.8% of non-tannery workers reported symptoms. About 12% of tannery workers were suffering from continuous productive cough (which throws out phlegm) while just 6% of non-tannery workers had this problem. Moreover, 24% of tannery workers reported that usually, they start coughing when they wake up in the morning. This number is much higher than what was reported by the non-tannery workers (11%). On symptoms of flu-like illness (aches and pains, fever, chills and night sweats), 50% of the tannery workers reported such symptoms, while it was 27% for non-tannery workers. A higher proportion of tannery workers also reported nasal allergies (12%) as compared to non-tannery workers (6%); and 18% of tannery workers reported chest congestion, as against 10% for non-tannery workers.
Table 3Prevalence of symptoms suggestive of Asthma among tannery and non-tannery workers in Kanpur, India, 2015.
| Symptoms suggestive of Asthma | Tannery workers (%) | Non-tannery workers (%) | Overall (%) |
|---|---|---|---|
| Wheezing or whistling in your chest at any time in the last 12 months | 12.3 | 8.7 | 10.5 |
| All breathless when the wheezing noise was present | 7.8 | 6.6 | 7.2 |
| Wheezing or whistling when you did not have a cold | 5.6 | 4.8 | 5.2 |
| Woken up with a feeling of tightness in your chest at any time in the last 12 months | 10.2 | 7.3 | 8.7 |
| Woken by an attack of shortness of breath at any time in the last 12 months | 6.3 | 3.8 | 5.1 |
| A cough most days and nights for at least 3 months in the previous year | 12.0 | 8.0 | 10.0 |
| A cough up phlegm most days or nights for at least 3 months in previous year | 11.6 | 5.9 | 8.7 |
| Usually, have a cough first thing in the morning | 23.9 | 11.1 | 17.5 |
| Usually bring up phlegm from your chest first thing in the morning | 20.1 | 14.2 | 17.1 |
| Brought up phlegm from your chest like this most mornings for at least 3 months in previous year | 10.2 | 8.0 | 9.1 |
| Had a flu-like illness with aches and pains, fever, chills, and night sweats in last 12 months | 50.0 | 26.6 | 38.2 |
| Usually have a cough | 19.4 | 13.2 | 16.2 |
| Have any nasal allergies | 12.3 | 6.2 | 9.3 |
| Usually experience through irritation | 10.9 | 7.3 | 9.1 |
| Usually experience chest contestation | 18.0 | 9.7 | 13.8 |
The prevalence of symptoms suggestive of Tuberculosis experienced by tannery and non-tannery workers in the last one year is presented in Table 4. A higher proportion of tannery workers experienced fatigue (26%), for non-tannery workers, it was 15%. About 19% of tannery workers reported frequent excessive sweating, especially at night. Around 6% of tannery workers reported frequent bouts of cough, usually with mucus, while it was 5% for non-tannery workers. A similar trend is observed for weight loss, breathing difficulty, and chest pain. Fifteen percent of tannery workers reported weight loss (as compared to 6% in the case of non-tannery workers). Nearly 9% of the tannery workers had frequent chest pain (it was 4% for non-tannery workers), and 18% of the tannery workers had a frequent fever (it was 7% for non-tannery workers).
Table 4Prevalence of symptoms suggestive of Tuberculosis experienced by tannery and non-tannery workers in last one year in Kanpur, India, 2015.
| Symptoms suggestive of Tuberculosis | Tannery workers | Non-tannery workers | ||||
|---|---|---|---|---|---|---|
| Often | Sometimes | Never | Often | Sometimes | Never | |
| Cough (usually with mucus) | 6.0 | 24.7 | 69.4 | 5.2 | 31.5 | 63.3 |
| Coughing up blood | 0.4 | 4.2 | 95.5 | 0.0 | 2.8 | 97.2 |
| Excessive sweating, especially at night | 19.0 | 12.7 | 68.3 | 9.0 | 11.4 | 79.6 |
| Fatigue | 25.7 | 38.7 | 35.6 | 14.5 | 35.0 | 50.5 |
| Fever | 18.3 | 33.8 | 47.9 | 6.6 | 24.9 | 68.5 |
| Weight loss | 14.8 | 21.5 | 63.7 | 5.9 | 11.4 | 82.7 |
The reported symptoms suggestive of Asthma and Chronic Bronchitis (CB) are presented in Table 5. On the prevalence of Asthma, it can be seen that it is higher among tannery workers than non-tannery workers across all age-groups. It is considerably higher among tannery workers (17%) who are in the age group of 16–24 years, while it was 5% among non-tannery workers in the same age group. The prevalence of symptoms suggestive of Asthma was found to be higher among tannery workers who were illiterate or had only primary education than similar non-tannery workers. The prevalence of symptoms suggestive of Asthma was higher among Muslim tannery workers (12%) than among Muslim non-tannery workers (6%). It was also higher among with tannery workers with a relatively higher standard of living (11%) as compared to similar non-tannery workers (3%). Prevalence of symptoms suggestive of chronic bronchitis was found to be higher among tannery workers in the age group of 36 years and above (13%). The corresponding figure for the non-tannery worker was 6.6%. Tannery workers who were illiterate or educated up to primary level had a higher proportion of CB (12–21%) as compared to those with middle or high school education (8-6%). Muslim tannery workers had a higher proportion of cases of chronic bronchitis (13%) as compared to non-tannery Muslim workers (4.7%).
Table 5Prevalence of symptoms suggestive of Asthma and Chronic Bronchitis reported by the tannery and non-tannery workers in Kanpur, India, 2015.
| Background variables | Tannery workers | Non-tannery workers | ||||
|---|---|---|---|---|---|---|
| Asthma | Chronic | Number (N) | Asthma | Chronic | Number (N) | |
| Bronchitis | Bronchitis | |||||
| Age in years | ||||||
| 16–24 | 17.2 | 10.3 | 29 | 5.0 | 10.0 | 21 |
| 25–35 | 11.7 | 10.7 | 103 | 8.1 | 3.5 | 85 |
| 36+ | 11.8 | 12.5 | 152 | 9.3 | 6.6 | 183 |
| Education | ||||||
| Illiterate | 14.4 | 11.8 | 187 | 10.1 | 7.8 | 179 |
| Up to primary | 10.5 | 21.1 | 38 | 3.9 | 0.0 | 26 |
| Middle school | 8.0 | 4.0 | 25 | 12.0 | 4.0 | 26 |
| High school & above | 6.1 | 6.1 | 33 | 5.2 | 3.5 | 58 |
| Religion | ||||||
| Hindu | 12.5 | 9.4 | 96 | 12.7 | 7.6 | 117 |
| Muslim | 12.2 | 12.8 | 188 | 5.9 | 4.7 | 172 |
| Caste | ||||||
| SC/ST | 14.0 | 14.0 | 186 | 11.4 | 9.5 | 105 |
| Other backward class | 5.8 | 11.5 | 52 | 4.0 | 1.0 | 98 |
| Others | 25.8 | 6.3 | 46 | 22.7 | 14.0 | 86 |
| Media exposure | ||||||
| Low exposure | 18.5 | 18.5 | 65 | 21.3 | 11.5 | 61 |
| Medium exposure | 10.9 | 10.9 | 138 | 7.4 | 4.9 | 122 |
| High exposure | 9.9 | 7.4 | 81 | 2.8 | 3.8 | 106 |
| Standard of living index | ||||||
| Low | 19.6 | 12.2 | 107 | 17.9 | 10.7 | 85 |
| Medium | 4.5 | 12.4 | 89 | 6.7 | 3.9 | 104 |
| High | 11.4 | 10.2 | 88 | 3.0 | 4.0 | 100 |
| Total | 12.3 | 11.6 | 284 | 8.7 | 5.9 | 289 |
A higher proportion of tannery workers belonging to SC/ST reported symptoms suggestive of chronic bronchitis (14%), while the corresponding figure for non-tannery workers was 9.5%. A higher proportion of tannery workers with low exposure to mass media reported chronic bronchitis. The percentage was significantly lower among a similar group of non-tannery workers (11.5%).
The odds of symptoms suggestive of chronic bronchitis among tannery workers are depicted in Table 6. After adjustment for age, education, religion, and caste of the tannery workers, the results show that the duration of employment in the tannery industry is a significant predictor. For instance, those who worked for 11 years and more were more likely to develop symptoms suggestive of chronic bronchitis (OR = 2.90; p < 0.10) as compared to those who had completed five years. Wet finishing workers are significantly less likely to develop chronic bronchitis (OR = 0.20; p < 0.05) than beam house worker. It was also seen that permanent tannery workers were more likely to develop chronic bronchitis than temporary workers.
Table 6Odds ratio showing risk factors of symptoms suggestive of Chronic bronchitis among tannery workers (3 month preceding the survey) in Kanpur, India, 2015.
| Independent variables | Model-I | C.I. | Model-II | C.I. |
|---|---|---|---|---|
| Age in years | ||||
| 16-24® | ||||
| 25–35 | 0.82 | [0.19–3.44] | 1.03 | [0.21–5.05] |
| 36+ | 0.99 | [0.24–4.09] | 0.63 | [0.12–3.23] |
| Education | ||||
| Illiterate® | ||||
| Up to primary | 2.75* | [1.03–7.33] | 3.04* | [1.03–8.97] |
| Middle school | 0.45 | [0.05–3.84] | 0.56 | [0.06–5.19] |
| High school & above | 1.05 | [0.19–5.85] | 1.03 | [0.16–6.45] |
| Religion | ||||
| Hindu® | ||||
| Muslim | 1.74 | [0.71–4.26] | 1.67 | [0.58–4.83] |
| Caste | ||||
| SC/ST® | ||||
| Other backward class | 0.73 | [0.26–2.04] | 0.79 | [0.26–2.35] |
| Others | 0.10* | [0.01–0.80] | 0.08** | [0.01–0.72] |
| Media exposure | ||||
| Low exposure® | ||||
| Medium exposure | 0.41* | [0.17–1.00] | 0.32** | [0.12–0.89] |
| High exposure | 0.35 | [0.10–1.30] | 0.21** | [0.05–0.88] |
| Standard of living index | ||||
| Low® | ||||
| Medium | 0.78 | [0.30–2.00] | 0.80 | [0.28–2.33] |
| High | 0.86 | [0.30–2.47] | 1.03 | [0.33–3.26] |
| Work experience in current tannery | ||||
| Up to 5 yrs® | ||||
| 6–10 yrs. | 0.89 | [0.28–2.80] | ||
| 11 & above yrs. | 2.90* | [0.97–8.64] | ||
| Type of work | ||||
| Beam house work® | ||||
| Wet finishing work | 0.20** | [0.05–0.86] | ||
| Dry finishing work | 0.43 | [0.12–1.50] | ||
| Miscellaneous work | 0.72 | [0.18–2.82] | ||
| Type of Job contract | ||||
| Temporary job (daily wages)® | ||||
| Permanent job | 1.36 | [0.32–5.78] | ||
| Chemicals in the Air | ||||
| No exposure® | ||||
| Low exposure | 0.69 | [0.17–2.83] | ||
| Moderate/High exposure | 2.55 | [0.32–20.22] | ||
| Airborne dust | ||||
| No exposure® | ||||
| Low exposure | 2.00 | [0.47–8.47] | ||
| Moderate/High exposure | 0.39 | [0.05–3.09] | ||
Note: ® Reference category, ***P < 0.01, **P < 0.05, *P < 0.1.
The odds of symptoms suggestive of Asthma among tannery workers are described in Table 7. Tannery workers who studied up to high school and above level of schooling are 0.4 (p < 0.1) times less likely to suffer from Asthma compare to illiterate workers in Model-1. Workers belong to the Muslim religion are 1.3 and 1.7 times more likely to have Asthma in Model-1 and Model-2 then Hindu workers, but results are not statistically significant. Work experience in current tannery has a statistically significant association with Asthma. Tannery workers who have 11 and above years of work experience are 2.5 (p < 0.1) times more likely to have Asthma than those who have five years of working experience in Model-2. Tannery workers engage in wet finishing work are 1.5 (p < 0.1) times more likely to have symptoms suggestive of Asthma in comparison to beam house workers. Tannery workers exposed to the chemicals in the air are at risk to have symptoms suggestive of Asthma. Tannery workers have moderate/high exposure are 3.9 (p < 0.05) times more likely to have symptoms suggestive of Asthma then those have no chemical exposure in the air.
Table 7Odds ratio showing risk factor of symptoms suggestive of Asthma among tannery workers (12 month preceding the survey) in Kanpur, India, 2015.
| Independent variables | Model-I | C.I. | Model-II | C.I. |
|---|---|---|---|---|
| Age in years | ||||
| 16–24 | ||||
| 25–35 | 0.51 | [0.15–1.71] | 0.4 | [0.10–1.67] |
| 36+ | 0.47 | [0.14–1.56] | 0.26 | [0.06–1.11] |
| Education | ||||
| Illiterate | ||||
| Up to primary | 0.93 | [0.28–3.08] | 1.08 | [0.28–4.14] |
| Middle school | 0.5 | [0.10–2.42] | 0.5 | [0.10–2.65] |
| High school & above | 0.39* | [0.07–2.16] | 0.24 | [0.03–1.59] |
| Religion | ||||
| Hindu | ||||
| Muslim | 1.3 | [0.56–3.05] | 1.70 | [0.62–4.66] |
| Caste | ||||
| SC/ST | ||||
| Other backward class | 0.37 | [0.10–1.33] | 0.36 | [0.09–1.47] |
| Others | 0.74 | [0.26–2.10] | 0.46 | [0.13–1.58] |
| Media exposure | ||||
| Low exposure | ||||
| Medium exposure | 0.64 | [0.26–1.59] | 0.70 | [0.26–1.92] |
| High exposure | 0.77 | [0.23–2.55] | 0.70 | [0.18–2.63] |
| Standard of living index | ||||
| Low | ||||
| Medium | 0.19** | [0.06–0.61] | 0.13** | [0.03–0.52] |
| High | 0.66 | [0.26–1.69] | 0.76 | [0.26–2.21] |
| Work experience in current tannery | ||||
| Up to 5 yrs. | ||||
| 6–10 yrs. | 1.06 | [0.32–3.47] | ||
| 11 & above yrs. | 2.51* | [0.87–7.27] | ||
| Type of work | ||||
| Beam house work | ||||
| Wet finishing work | 1.54* | [0.33–7.24] | ||
| Dry finishing work | 0.45 | [0.10–2.07] | ||
| Miscellaneous work | 0.84 | [0.16–4.41] | ||
| Type of Job contract | ||||
| Temporary job (daily wages) | ||||
| Permanent job | 4.59 | [1.38–15.28] | ||
| Chemicals in the Air | ||||
| No exposure | ||||
| Low exposure | 1.75 | [0.49–6.31] | ||
| Moderate/High exposure | 3.86** | [0.59–25.39] | ||
| Airborne dust | ||||
| No exposure | ||||
| Low exposure | 0.80 | [0.21–2.97] | ||
| Moderate/High exposure | 0.13** | [0.02–0.82] | ||
Note: ® Reference category, ***P < 0.01, **P < 0.05, *P < 0.1.
5. Discussion
This study is a cross-sectional household study based on primary data that covers the tannery and non-tannery workers in the Jajmau area of Kanpur City in the state of Uttar Pradesh. The study attempts to estimate the prevalence of asthma, tuberculosis, and chronic bronchitis among tannery workers and to identify the factor associated with it. Findings revealed that the majority of the tannery workers or non-tannery workers were aged 36 years and above, illiterate, married, and belong to the Muslim community. There is only a small variation in the corresponding figures for non-tannery workers because the study area was predominantly Muslim. The present study indicates that most people from disadvantageous social caste groups were engaged in tannery work.
The findings revealed that the prevalence of symptoms of asthma, tuberculosis, and chronic bronchitis among the tannery workers was higher compared to non-tannery workers. The difference might be because of tannery industry workers were more likely to be exposed to various workplace hazards associated with tannery activities, such as chemical hazards, including chromium salt, acids, dyes, and leather dust, and biological hazards from rawhides that might exacerbate respiratory symptoms.
1
,5
,13
,14
Several studies have observed the differences in the prevalence of asthma between tannery workers and non-tannery workers in Kenya,15
Egypt,16
,17
Pakistan,5
India,18
,19
and Turkey.14
Findings revealed that the majority of the tannery workers were engaged in dry and wet finishing type of work. While processing dry and wet finishing type of leather tannery work, they exposed to Chromium and leather dust through inhalation. For instance, Chromium enters the body through the respiratory system and produces its toxic effects like nasal allergy, nasal septal perforation, irritation in the throat, bronchial asthma, alteration in lung function, and tumours in the nose, throat, and lung. Other chemicals like organic acids are respiratory irritants and may cause the destruction of the upper and lower respiratory tract.
2
The findings of the study revealed that illiterate tannery workers were more at risk of having asthma or chronic bronchitis. A study conducted in Bangladesh in the general population has also revealed that illiterate were at greater risk of asthma.
20
Another research has also shown education to be protective for asthma.21
The mechanism by which education may have its protective effect against asthma might be by improved general health and wellbeing of the subject and by increased awareness about triggering factors, subsequently avoidance of exposure to such factors.5
The study revealed that long time tannery working harms health, as tannery workers are more likely to be suffering from asthma and chronic bronchitis who worked above 11 years in the tannery (p-value 0.62). A study in Bangladesh among tannery workers has also revealed that a longer duration of engagement in tannery work has a greater risk of the respiratory problem.
5
,22
Findings have shown that most of the male tannery workers are working on temporary job contracts. Although in this study, employment status or job contract was not significant, but it may be a significant factor of respiratory symptoms because temporary workers had a higher risk of developing respiratory symptoms compared to workers work permanently. The possible reason might be differences in the facilities provided by the industry to permanent and temporary workers. Therefore, temporary workers have limited access to basic safety training and the use of personal protective devices. Furthermore, such groups of workers are usually forced to do more tasks for fear of losing their jobs for more time.4
,23
, 24
, 25
6. Conclusions
The study concludes that the symptoms of Tuberculosis, such as excessive sweating, especially at night, fever, weight loss, breathing difficulty and chest pain were more than two times higher among the tannery workers then non-tannery workers. So, tannery workers are prone to get infected from the Tuberculosis. From the findings of this study, it can understand that the age, education, media exposure, working hours in the tannery, type of work engagement within tannery occupation, and exposure to chemicals are the major risk factors for asthma and chronic bronchitis among the male tannery workers. There must be orientation programs to raise awareness of health hazards associated with the tannery work. Workers must be educated about preventive measures and be motivated to use them during work. Regular medical check-ups, along with physiological counselling, must be conducted. Specific health insurance facilities should be provided, such as the Employee's State Insurance Scheme (ESIS), from the day a person begins work in a tannery.
7. Limitations of the study
In a cross-sectional survey, there is a possibility to get underestimated the prevalence of morbidities. In response to self-reported morbidities, there could be some biasedness due to subjectivity in responses as the severity was not quantified more precisely, and the recall bias may also affect the estimated prevalence of morbidities.
Ethics approval and consent to participate
We have received ethical clearance from the committee. The Student Research Ethics Committee of the International Institute for Population Sciences, Mumbai, India approved the study. We have also received formal written consent to participate from each of the respondents before starting the interview.
Availability of data and material
This study is based on the primary data. We would like to share the data set with the editor of the journal.
Authors’ contributions
GCK conceived the idea and analysed the data. SSS designed the manuscript and, interpreted the results, discussion and drafted the manuscript. SKS has reviewed the paper. The final manuscript has been read and approved by all the authors.
Funding
No fund was available for this research.
Declaration of competing interest
The authors have no conflicts of interest to declare. This study is based on the primary data. We would like to share the data set with the editor of the journal, and no fund was available for this research.
Acknowledgements
The authors of the study are also thankful to the respondents of the study.
References
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Article info
Publication history
Published online: July 15, 2020
Accepted:
July 7,
2020
Received in revised form:
June 22,
2020
Received:
May 17,
2020
Identification
Copyright
© 2020 Published by Elsevier, a division of RELX India, Pvt. Ltd on behalf of INDIACLEN.
