Evaluation of Dust Exposure among the Workers in Agricultural Industries in North-East India

Evaluation of dust and endotoxin exposure among rice mill workers in northeast India

Exposure to particulate matter and endotoxin can lead to acute and chronic respiratory problems in workers. A study was conducted to quantify particulate matter with an aerodynamic diameter of ≤10 μm (PM10) and endotoxin levels in rice mills in northeast India. Sixty-four PM10 dust samples were collected from eight rice mills at two locations: the feeding and polishing sections for two varieties of paddy: Ranjit and Hali. Endotoxin exposures were analyzed using the Limulus Amoebocyte Lysate (LAL) gel clot test. The results showed that the geometric mean of the 8-h time-weighted average (TWA) PM10 dust concentration and endotoxin level in the rice mills were 10.69 mg/m³ and 2.2 EU/m³, respectively. Dust and endotoxin exposure were higher in the feeding section than in the polishing section. Endotoxin exposure in the feeding section during the milling of the Hali variety of paddy was 56.0 % higher than the milling of the Ranjit variety. Additionally, endotoxin exposure during the milling of the Hali variety was 24.2 % higher than that of the milling of the Ranjit variety in the polishing section. The dust exposure in the rice mills was 194.5 % higher than the standards set up by the United States Environmental Protection Agency. However, the exposure to endotoxin in rice mills was approximately 40.10 times below the recommended limit of 90 EU/m3.

Effect on pulmonary functions of dust exposed rice mill workers in comparison to an unexposed population

BACKGROUND

Paddy milling is the oldest and largest agro-processing industry in India. A large number of workers are employed in the rice mills where they are potentially exposed to dust. It has been shown that exposure to dust results in a high prevalence of respiratory diseases, such as asthma, chronic bronchitis, extrinsic allergic alveoli ties, toxic syndrome, and interstitial lung disease.

OBJECTIVE

The aim of this study was to investigate the effect of dust on rice mill workers' health using lung function tests with comparison to an unexposed population.

PARTICIPANTS

Two hundred eighteen rice mill workers (exposed volunteers) were randomly selected from 25 rice mills in Assam, India. Participants were 18-60 years with at least one year of work experience. Further, 377 volunteers who were not exposed to dust and having similar demographic characteristics also participated as a control group.

METHOD

Pulmonary function tests were conducted for all participants by spirometry. The tests included forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC (%), peak expiratory flow (PEF) and forced expiratory flow during the middle half of a forced vital capacity (FEF25-75%). Values from exposed workers were compared with the unexposed volunteers.

RESULTS

It was observed that the lung function parameters FVC, FEV1, PEF and FEF25-75% in exposed workers were significantly decreased compared with unexposed volunteers. There were also significantly decreased FVC, FEV1, FEV1/FVC%, PEF and FEF25-75% with increase in age and duration of dust exposure. It was further observed that 48% and 32% of the total male and female volunteers, respectively, had evidence of lung disease. Irrespective of gender, approximately 45% of mill workers had evidence of lung disease, of which 21% was restrictive and 24% was obstructive.

CONCLUSION

Compared with unexposed controls, rice mill workers have a greater prevalence of respiratory disease based on pulmonary function tests.

Morbidities of rice mill workers and associated factors in a block of West Bengal: A matter of concern

Context:

Rice mill workers usually belong to unorganized sector and lack in training regarding hazard prevention. Unprotected exposure to suspended particles and fumes can lead to respiratory morbidities among them. Workers, especially loaders, were susceptible to work-related musculoskeletal diseases.

Aim:

To find out the morbidity profile and associated factors among rice mill workers.

Methodology:

A cross-sectional workplace-based study was conducted during July--September 2018 among 143 workers of two rice mills in Indas block, West Bengal. Workers, employed for at least 6 months in the rice mills and who gave informed written consent was interviewed using a predesigned pretested questionnaire and were clinically examined. Nonfasting capillary blood glucose estimation and spirometry were carried out. Workers contraindicated to spirometry were excluded.

Result:

Commonest morbidities were musculoskeletal discomfort (65%), hypertension (20.9%), and chronic respiratory morbidity (16.9%). No personal protective equipment (PPE) was used by these workers. Significant association of musculoskeletal discomfort was found with tobacco abuse (Adjusted Odds Ratio (AOR) =2.90), job of loader (AOR = 3.51), and central obesity (AOR = 3.39). Hypertension was significantly associated with increasing age (AOR = 1.06), and increasing body mass index (AOR = 1.17). Whereas increasing age (AOR = 1.08), working inside mill (AOR = 7.58), working more than 48 hours a week (AOR = 7.37) were significantly associated with chronic respiratory morbidity.

Conclusion:

Optimization of working hours, effective continuous use of PPE, and use of proper ventilation technology are recommended. Proper work placement, preplacement examination, and periodic health screening with spirometry are also needed.