Vibration dose and carpal tunnel syndrome in sandstone quarry workers: A cross-sectional study from Thailand.

Carpal tunnel syndrome (CTS) is common in vibration-exposed occupations, but evidence from informal sandstone workers is limited. This cross-sectional study examined hand-wrist symptoms and the association between cumulative hand-arm vibration exposure and CTS severity among 92 sandstone workers. Data were collected through structured interviews and ergonomic observation, and CTS severity was assessed using the Boston Carpal Tunnel Questionnaire-Symptom Severity Scale (BCTQ-SSS). CTS (mild or greater severity) was observed in 58.7% of workers. Compared with the lowest exposure quartile (Q1), workers in the highest quartile (Q4) had significantly higher symptom severity scores (adjusted β = 3.84; 95% CI 0.81-7.25; p = 0.049). A significant linear trend across quartiles was observed (adjusted p-trend = 0.029), supporting a dose-response relationship and highlighting the need for preventive controls in informal quarry settings.