BACKGROUND:
Occupational Noise-Induced Hearing Loss (ONIHL) is one of the most prevalent and underrecognized occupational diseases globally. In India, where tea processing is a major industry, limited research exists on ONIHL among tea factory workers. This study aimed to estimate the prevalence of ONIHL and identify its associated risk factors in black tea factories in Darjeeling, West Bengal.

METHODS:
A cross-sectional study was conducted from February 2022 to April 2024 across six selected black tea processing factories in Darjeeling. Using Cochran’s formula and multistage random sampling, 312 workers were recruited. Participants were interviewed using a structured questionnaire, and hearing was assessed via portable audiometry. Multivariate logistic regression identified predictors of ONIHL, adjusted for age, sex, work duration, and job station.

RESULTS:
Among the 312 participants (mean age 34.1±9.6 years; 77.2% male), the prevalence of ONIHL was 28.8%. The highest rates were found among workers in the Crushing-Tearing-Curling (CTC) room (44.8%), followed by maintenance (37.5%) and withering (28.2%) areas. Key predictors included working in CTC (AOR=28.08), withering (AOR=24.61), maintenance (AOR=13.89), and packing areas (AOR=15.72), male sex (AOR=2.97), and increasing age (AOR=1.03). Notably, none of the workers used personal protective equipment.

CONCLUSIONS:
ONIHL is a significant but overlooked occupational health issue in Indian tea processing factories. Specific job roles, male sex, and age significantly elevate risk. The absence of hearing protection in the workers points towards an urgent need for policy enforcement, workplace safety education, and provision of personal protective equipment to mitigate ONIHL in this sector.