Abstract
Jute mill workers are chronically exposed to organic dust containing plant fibers, endotoxins, and microbial contaminants, increasing their risk of respiratory morbidity. This cross-sectional study estimated the prevalence, patterns, and determinants of both symptomatic and spirometry-confirmed respiratory morbidity among 125 randomly selected workers in a jute mill in Howrah, West Bengal, between September 2024 and February 2025. Data on sociodemographic profile, occupational exposure, tobacco use, respiratory symptoms, and personal protective equipment (PPE) use were collected through structured interviews. Spirometry was performed using recorders and medicare systems (RMS) Helios 401 according to standardized guidelines. Nearly half of the workers (47.2%) reported at least one chronic respiratory symptom. Spirometry detected respiratory morbidity in 26.4% workers, predominantly restrictive (13.6%), followed by obstructive (8.8%) and mixed patterns (4.0%). Regular PPE use was reported by only 6.4% of workers. Multivariable logistic regression showed increasing age to be the only independent predictor of spirometry-confirmed morbidity (AOR 5.36; 95% CI 1.56–18.51). These findings highlight a substantial burden of occupational respiratory morbidity among jute mill workers and underscore the need for improved dust control, consistent PPE use, and periodic respiratory health surveillance.
Keywords: Jute industry, occupational lung disease, personal protective equipment, spirometry
INTRODUCTION
Jute processing is a major agro-industrial occupation in eastern India involving dust-intensive operations such as batching, carding, drawing, spinning, and weaving. These processes generate organic dust composed of plant fibers, endotoxins, and microbial contaminants capable of inducing airway inflammation and long-term pulmonary impairment. Respiratory disorders resembling byssinosis, classically described among cotton textile workers, have also been reported among jute mill workers.[1,2] Inhaled organic dust provokes inflammatory responses, bronchial hyper-responsiveness, and progressive reduction in lung function.[3] Workers frequently present with cough, chest tightness, wheeze, and dyspnea, while spirometry may reveal restrictive or obstructive ventilatory defects.[4]
Despite the large workforce employed in the jute industry, epidemiological evidence on respiratory morbidity remains limited. Poor ventilation, variable dust exposure, inconsistent personal protective equipment (PPE) use, and inadequate occupational health surveillance contribute to continued disease burden.[5] This study therefore assessed the prevalence and pattern of respiratory morbidity among jute mill workers and explored associated demographic, behavioral, and occupational factors.
METHODS
Study design and sampling
A cross-sectional observational study was conducted between September 2024 and February 2025 in a selected jute mill in Howrah district, West Bengal. Workers employed for ≥12 months were eligible. The sampling frame consisted of the complete employee register (n = 1982). Sample size was calculated using a previously reported prevalence of respiratory morbidity of 43.2%,[5] with 95% confidence level and 9% absolute precision. After adding 10% for non-response, 127 workers were required.
Simple random sampling using computer-generated random numbers was applied to select participants. Two workers declined participation, resulting in a final sample of 125.
Data collection
A pretested structured interview schedule collected information on sociodemographic characteristics, occupational history, tobacco and alcohol use, PPE use, and chronic respiratory symptoms. Symptom questions were adapted from a validated bioaerosol health questionnaire.[6]
Chronic respiratory symptoms assessed included chest tightness, shortness of breath, cough, and wheezing or whistling in the chest. Participants reporting symptoms were further classified by severity. Symptoms occurring only during episodes of the common cold were categorized as mild. Symptoms that had increased in frequency or severity over the past three months, irrespective of cold, were classified as moderate. Symptoms severe enough to disturb sleep at night were classified as severe.
Operational definitions
Symptomatic respiratory morbidity: Presence of one or more chronic respiratory symptoms lasting at least three months in the past year.
Work-years of exposure can be calculated using the following formula: (Hours worked per day × Days worked per month × Months worked per year × Years worked) ÷ (48 × 52).
Pack-years of smoking: Smoking 43 bidis per day for one year was considered equivalent to one pack-year.[7]
Spirometry-confirmed respiratory morbidity:
Obstructive defect: FEV1/FVC <0.70
Restrictive defect: FEV1/FVC ≥0.70 with FVC <80% predicted
Mixed defect: Both abnormalities present
Spirometry
Spirometry was performed using RMS Helios 401 following international standardization guidelines.[8] At least three acceptable maneuvers were recorded.
Statistical analysis
Descriptive statistics were followed by univariate logistic regression. Variables with P < 0.25 were entered into multivariable logistic regression. Statistical significance was set at P < 0.05. Ethical approval and written informed consent were obtained.
RESULTS
All 125 participants were male with a median age of 45 years (range 22–62). Most (80%) had more than 10 work-years of exposure. Current smoking was reported by 24.8%, and smokeless tobacco use by 50.4%. Only 6.4% reported regular use of respiratory PPE.
Nearly half (47.2%) had symptomatic respiratory morbidity. Cough was the most frequent symptom, followed by shortness of breath, wheeze, and chest tightness. Most symptoms were mild in severity, though moderate and severe symptoms were also observed [Table 1].
Table 1.
Severity distribution of chronic respiratory symptoms among jute mill workers (n=125)
| Symptom | Mild n (%) | Moderate n (%) | Severe n (%) | Total n (%) |
|---|---|---|---|---|
| Chest tightness | 24 (19.2) | 2 (1.6) | 1 (0.8) | 27 (21.6) |
| Shortness of breath | 24 (19.2) | 4 (3.2) | 3 (2.4) | 31 (24.8) |
| Wheeze/whistling | 25 (20.0) | 2 (1.6) | 2 (1.6) | 29 (23.2) |
| Cough | 23 (18.4) | 26 (20.8)* | — | 49 (39.2) |
| Any one chronic respiratory symptom | — | — | — | 59 (47.2) |
*Moderate-to-severe cough grouped
Spirometry revealed objective respiratory morbidity in 26.4% workers. Restrictive defects predominated (13.6%), followed by obstructive (8.8%) and mixed patterns (4.0%) [Table 2].
Table 2.
Pattern of spirometry-confirmed respiratory morbidity among jute mill workers (n=125)
| Spirometry pattern | n (%) |
|---|---|
| Normal lung function | 92 (73.6) |
| Restrictive ventilatory defect | 17 (13.6) |
| Obstructive ventilatory defect | 11 (8.8) |
| Mixed ventilatory defect | 5 (4.0) |
| Any spirometry-confirmed respiratory morbidity | 33 (26.4) |
Multivariable logistic regression analysis demonstrated that increasing age was significantly associated with spirometry-confirmed morbidity [Table 3].
Table 3.
Multivariable logistic regression analysis showing factors associated with spirometry-confirmed respiratory morbidity among jute mill workers (n=125)
| Variable included in the model | Adjusted odds ratio (AOR) | 95% Confidence interval |
|---|---|---|
| Age (in completed years) | 5.36 | 1.56–18.51 |
| Work-years of exposure (≥20 vs<20) | 0.41 | 0.12–1.37 |
| Pack-years of smoking (≥4 vs<4) | 0.81 | 0.25–2.55 |
| Respiratory PPE use (Irregular vs Regular) | 3.31 | 0.33–33.26 |
| Education level (Below primary vs Primary+) | 1.67 | 0.57–4.92 |
| Household crowding (Yes vs No) | 0.67 | 0.27–1.61 |
| Knowledge of respiratory hazards (Inadequate vs Adequate) | 0.49 | 0.06–4.59 |
DISCUSSION
This study shows a considerable burden of respiratory morbidity among jute mill workers, with nearly half reporting chronic symptoms and over one-quarter demonstrating spirometry-confirmed impairment. These findings are consistent with earlier Indian research where Chattopadhyay et al.[5] reported byssinosis-like symptoms and reduced lung function among jute workers exposed to high dust levels. Similar respiratory symptom prevalence and pulmonary function impairment have been observed among dust-exposed textile workers in Nepal,[6] indicating a broader regional pattern of occupational dust-related respiratory disease.
The predominance of restrictive ventilatory defects in this study is in line with known inflammatory and parenchymal effects of chronic organic dust inhalation.[1,2] The higher prevalence of symptoms compared to spirometry abnormalities may reflect early or intermittent disease not yet detectable by lung function testing.
Increasing age emerged as the only independent predictor of spirometry-confirmed morbidity, likely reflecting cumulative occupational exposure. The lack of independent association with smoking suggests that workplace dust exposure may be the primary determinant of lung impairment, as also noted in earlier studies.[5] Low use of respiratory PPE highlights an important and modifiable occupational health gap.[9]
This study has some limitations. Quantitative dust measurements were not available, limiting exposure–response assessment. The cross-sectional design precludes causal inference, and bronchodilator reversibility testing could not be performed to further characterize obstructive defects. Despite these limitations, standardized spirometry and structured symptom assessment strengthen the validity of the findings.
CONCLUSION
Respiratory morbidity remains common among jute mill workers, with both symptoms and spirometric abnormalities indicating significant occupational health risk. The findings underscore the need for improved dust control, consistent use of respiratory protective equipment, and regular respiratory health surveillance to prevent long-term lung disease.
Ethical approval
Institutional Ethics Committee, All India Institute of Hygiene and Public Health, Kolkata.
Conflicts of interest
There are no conflicts of interest.
Acknowledgment
The authors express their sincere gratitude to Fort William Jute Mill Authority for extending support to conduct the study. We are also deeply thankful to the jute mill workers who participated in the study and generously shared their time and experiences. We acknowledge our institution for providing guidance and ethical approval to carry out this research.
Funding Statement
Nil.
REFERENCES
- 1.Poole JA, Zamora-Sifuentes JL, Vecillas LD, Quirce S. Respiratory diseases associated with organic dust exposure. J Allergy Clin Immunol Pract. 2024;12:1960–71. doi: 10.1016/j.jaip.2024.02.022. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Gilson JC, Stott H, Hopwood BE, Roach SA, McKerrow CB, Schilling RS. Byssinosis in textile workers. Br J Ind Med. 1962;19:9–18. doi: 10.1136/oem.19.1.9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.World Health Organization. Geneva: WHO; 2021. WHO global air quality guidelines. [Google Scholar]
- 4.Chen J, Lou J, Guo X, Zhou C. Pulmonary function in jute dust-exposed workers. J Occup Health. 1997;39:313–8. [Google Scholar]
- 5.Chattopadhyay BP, Saiyed HN, Mukherjee AK. Byssinosis among jute mill workers. Ind Health. 2003;41:265–72. doi: 10.2486/indhealth.41.265. [DOI] [PubMed] [Google Scholar]
- 6.Basu S, Poole J, Frost G, Fox D. Questionnaire to assess bioaerosol health effects. Occup Med (Lond) 2018;68:448–53. doi: 10.1093/occmed/kqy094. [DOI] [PubMed] [Google Scholar]
- 7.Datta R, Singh S, Joshi A, Marwah V. Concept of bidi-years. Lung India. 2022;39:337–42. doi: 10.4103/lungindia.lungindia_595_21. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Miller MR, Hankinson J, Brusasco V, Burgos F, Casaburi R, Coates A, et al. Standardisation of spirometry. Eur Respir J. 2005;26:319–38. doi: 10.1183/09031936.05.00034805. [DOI] [PubMed] [Google Scholar]
- 9.Singh SB, Gautam S, Bhatta N, Shrestha G, Gautam R, Poudel S. Respiratory disorders among dust-exposed workers. JNMA J Nepal Med Assoc. 2019;57:14–9. doi: 10.31729/jnma.3987. [DOI] [PMC free article] [PubMed] [Google Scholar]