title: Effect of tractor driving on hearing loss in farmers in India.
abstract: BACKGROUND
  Indian tractor drivers operate their tractors and other implements/equipment in an environment which can have extreme temperatures and high level of suspended particulate matter. In addition, Indian tractors do not have adequate vibration and noise attenuating designs features. This cross-sectional study compares the hearing status of tractor driving farmers (TDFs) (study group) and non-tractor driving farmers (NTDFs) (control group) matched for age, sex, generic/ethnic group, land holding, education levels, and work routines.
  
  
  METHODS
  Two groups of 50 experienced tractor-driving farmers and 50 non-driving farmers were selected from 2 villages, 50 km from Delhi. All participants were interviewed for details of work routine and noise exposures. An audiogram was performed and noise measurements taken on tractors and other machines.
  
  
  RESULTS
  Self-reported hearing problems were similar (4 cases each) in both the groups of 50 farmers. However, audiogram analysis showed higher prevalence of abnormalities in TDFs. TDFs (24) had more often high frequency hearing loss when compared to NTDFs (14). The noise levels observed on tractors in different operations were in the range of 90-110 dB (A).
  
  
  CONCLUSIONS
  Tractor noise levels exceeded the recommended safe limits of OSHA and NIOSH prescribed standards. TDFs had higher high frequency hearing loss than NTDFs. The mechanism of damage and prevention needs to be studied further.
authors.affiliation: Division of Agricultural Engineering, Indian Agricultural Research Institute, New Delhi, India. adarsh_iari@rediffmail.com
authors.forename: Adarsh
authors.initials: A
authors.lastname: Kumar
authors.forename: N N
authors.initials: NN
authors.lastname: Mathur
authors.forename: Mathew
authors.initials: M
authors.lastname: Varghese
authors.forename: Dinesh
authors.initials: D
authors.lastname: Mohan
authors.forename: J K
authors.initials: JK
authors.lastname: Singh
authors.forename: Punnet
authors.initials: P
authors.lastname: Mahajan
mesh_terms: D000328:Adult; D000382:Agricultural Workers' Diseases / Q000453:epidemiology*; D001299:Audiometry; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D006317:Hearing Loss, Noise-Induced / Q000453:epidemiology*; D006801:Humans; D007194:India / Q000453:epidemiology; D008875:Middle Aged; D018986:Motor Vehicles; D012307:Risk Factors