title: Comparative study of audiometrics tests on metallurgical workers exposed to noise only as well as noise associated to the handling of chemical products.
abstract: Exposure to ototoxic chemical products in the presence or absence of noise can cause irreversible injury to the hearing of workers for a significantly short period of exposure period.
  
  
  OBJECTIVE
  to perform a comparative study, through audiometric tests, in workers exposed to noise only and noise associated with chemical products.
  
  
  METHODS
  155 steel workers (18 - 50 years) exposed to noise (group I), and exposed to noise and chemical products (group II) for a period that varies from 3 to 20 years.
  
  
  RESULTS
  significant difference in the rate of occupational hearing loss in the right ear between groups I (3.6%) and II (15.5%). A significantly higher rate of occupational hearing loss in group II (18.3%) and I (6%). With respect to the average time of exposure to aggressive agents, group I was exposed by a significantly higher time. Retrospective study.
  
  
  CONCLUSIONS
  The fact that the right ear was more affected in group II is controversial and should be better investigated in the future, since some studies show that the left ear would be more prone to noise-induced hearing loss.
  
  
  CONCLUSIONS
  group II had proportionally a higher rate of hearing loss when compared with group I, even after having been exposed to aggressive agents for a lower average time.
authors.affiliation: Centro de Especialização em Fonoaudiologia Clínica.
authors.forename: Carla Tomaz
authors.initials: CT
authors.lastname: Botelho
authors.forename: Anna Paulla Maia Lopes
authors.initials: AP
authors.lastname: Paz
authors.forename: André Martins
authors.initials: AM
authors.lastname: Gonçalves
authors.forename: Silvana
authors.initials: S
authors.lastname: Frota
mesh_terms: D000293:Adolescent; D000328:Adult; D001299:Audiometry; D001309:Auditory Threshold; D016022:Case-Control Studies; D006317:Hearing Loss, Noise-Induced / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009623:Noise, Occupational / Q000009:adverse effects* / Q000706:statistics & numerical data; D016273:Occupational Exposure / Q000009:adverse effects* / Q000706:statistics & numerical data; D015995:Prevalence; D013997:Time Factors; D055815:Young Adult