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Total communication: This method represents the simultaneous use of spoken language and English-based signed language. Noise-induced hearing loss has been studied for many years and today many experts also investigate the synergic action of chemical products, since they can be potentially ototoxic. Aim: to investigate the audiological findings in workers exposed to occupational noise and pesticide and to compare it to data from noise-exposed workers.
Study Design: Clinical retrospective.
Material and Method: individuals that had been exposed to pesticide and noise (group I), and individuals that had been exposed to noise only (group II). Results: The classification of the audiometric findings showed in that group I: 35% had normal hearing thresholds, 53.75% had degree 1 hearing loss and 11.25% had degree 2 hearing loss; and group II had 57.5% of normal hearing, 40% had degree 1 hearing loss and only 2.5% had degree 2 hearing loss. The analysis of the audiometric findings also showed a significant worsening after comparing groups I and II thresholds, in the frequency of 3 kHz on the left ear and 4 kHz on both ears.
Conclusion: The analysis showed that group I had worse audiometric thresholds compared to groups. Thanks to technological development, the most spread type of pollution is sound pollution, and everyone is subject to being exposed to noise levels which are harmful for human health. Noise, by itself, is harmful to health when the sound level is higher than 85 dB, depending on the duration and the systematic exposure to it. For this reason, based on this sound intensity, audiometries are periodically carried out in industrial plants.
Noise induced hearing loss (NIHL) happens because of the systemic and prolonged exposure to intense noise, it is a chronic and irreversible disease, since it involves the hair cells of the organ of Corti. This disorder is also recognized by numerous authors as the most prevalent occupational-related disorder.
NIHL initially affects the frequencies of 6, 4 or 3 kHz; and with the progression of the loss, it can reach the regions of 8, 2, 1 kHz, 500 and 250 Hz. Moreover, the individual can have tinnitus and discomfort related to intense sounds, and once the noise exposure ends, there is no more hearing loss progression. Exposure duration and individual susceptibility are also factors which can impact disease onset.