Background

We determined the effectiveness of a multifaceted intervention package in reducing dust levels in cotton mills, decreasing the frequency of respiratory symptoms among cotton textile workers, and improving their lung function.

Methods

We undertook a cluster-randomised controlled trial at 38 textile mills in Karachi. The intervention comprised: training in occupational health for all workers and managers backed by regular refresher sessions; the formation of workplace committees to draw up, agree and promote a health and safety plan; and provision of face masks. Mills were randomised to intervention and control arms following a baseline survey. The impact of the intervention was determined through follow-up surveys at 3, 12 and 18 months. The data collected included spirometry, questionnaire-based interviews, and cotton dust measurements.

Findings

Of the 2031 participants recruited at baseline, 807 (40%) were available at the third follow-up survey. Baseline characteristics and losses to follow-up were similarly distributed across the two arms. At the third follow-up, workers in the intervention arm were more likely to report an improvement in the respiratory symptoms (composite outcome, OR: 1.58; 95% CI: 1.06-2.37) and lung function (percentage predicted FEV1, β: 1.31%; 95% CI: 0.04-2.57). There was no improvement in cotton dust exposure.

Interpretation

We found the multifaceted intervention package to be effective in improving respiratory health of cotton textile workers and recommend scaling-up of such simple and feasible interventions in low- and middle-income countries.