Audiological findings among workers from Brazilian small-scale fisheries

The aim of this study was to examine the noise exposure and hearing of fishermen from small-scale fisheries from the state of Paraná in Brazil.

Participants of this cross-sectional study included 141 male fishermen, ages ranging from 18 to 77 yr old and 136 controls matched by socioeconomic level, age, and gender. We conducted personal noise dosimetry and interviewed the fishermen regarding their hearing and their job. Audiological testing performed included pure-tone audiometry in the 0.5 to 8 kHz frequency range, extended high-frequency audiometry in the 9 to 16 kHz range, and transient and distortion-product otoacoustic emissions. Testing was preceded by a period of at least 14 hr without exposure to noise. Participants were subdivided in subgroups according to their noise exposure history.

Sound level measurement results ranged from 38 to 58 Leq dB (A) in vessels without an engine and between 90 and 108 Leq dB (A) in vessels with an engine. Results from additional area sound level measurements conducted in five different seating locations in the 9HP engine boat ranged from 86 to 105 dB (A). Statistical analysis of the pure-tone audiometry results showed that fishermen with current or a history of occupational noise exposure had significantly poorer thresholds than controls or unexposed fishermen in several of the tested audiometric frequencies. Results of the otoacoustic emissions testing showed differences between exposed and unexposed groups regarding the presence of responses in bilateral amplitude and reproducibility at all frequency bands tested.

Because of the fishermen's increased risk of hearing disorders, a variety of solutions are recommended, which include dissemination of information on control of noise emissions generated by the boat engines, audiological care, and hearing loss prevention services tailored to workers from small-scale fisheries.