Voice characteristics of iron and steel workers: an acoustic and self-reported cross-sectional study

Occupational environments with dust, noise, and high vocal demands can adversely impact voice production. Iron and steel workers encounter several environmental risk factors that may impair vocal function, nevertheless, objective acoustic and self-reported voice outcomes in this population have not been thoroughly investigated. This study aimed to evaluate the acoustic and self-reported voice characteristics of iron and steel manufacturing workers and compare these findings with those of a normophonic control group.

This cross-sectional comparative research comprised 128 male participants: 64 steel and iron factory workers and 64 normophonic controls. Voice evaluation consisted of F0, jitter, shimmer, noise-to-harmonics ratio, smoothed cepstral peak prominence, Acoustic Voice Quality Index, maximum phonation time, Voice Handicap Index-10 and Voice-Related Quality of Life. Mann-Whitney U tests or Welch's t-tests were used for between-group comparisons, as appropriate.

Iron and steel workers had significantly lower F0 and smoothed cepstral peak prominence values and higher jitter, shimmer, noise-to-harmonics ratio, and Acoustic Voice Quality Index scores than controls (all p < 0.01). The maximum phonation time was significantly shorter in workers (p < 0.001). The mean Voice Handicap Index-10 score among workers exceeded the Turkish threshold, and the Voice-Related Quality of Life scores were significantly lower than those of controls (p < 0.001).

Iron and steel industry workers had lower acoustic and self-reported markers of voice quality than normophonic individuals. These findings indicate that exposure to industrial noise and airborne irritants may be associated with subclinical changes in voice characteristics. In occupational health, a comprehensive voice assessment can serve as a time-saving, non-invasive screening tool to support early diagnosis and prevention of work-related voice problems.