title: Impairment of color vision in aircraft maintenance workers.
abstract: OBJECTIVE
  The purpose of the study was to examine possible persisting effects to color vision in a group from the Royal Australian Air Force who had exposure to formulations containing neurotoxins during F-111 fuel tank maintenance, relative to two contemporaneous comparison groups.
  
  
  METHODS
  Color vision was tested in 512 exposed personnel, 458 technical-trade comparisons, and 330 non-technical comparisons using the Ishihara test plates and the Lanthony D-15 Desaturated Color disk arrangement test. Participants were excluded if they failed the Ishihara test as this indicates congenital color blindness. From the Lanthony results, the type of color deficient vision (CDV) was diagnosed, and additionally, the Bowman's color confusion index (CCI) was calculated. Regression models were used to examine whether there was an association between color vision deficiencies and F-111 fuel tank maintenance, adjusting for possible confounders.
  
  
  RESULTS
  The CCI ranged from 1 to 2.8 (median 1.2, quartiles 1.1, 1.4) in the 2,600 eyes tested. Forty five percent of all participants had blue-yellow CDV in at least one eye. Deficiencies of this nature are caused by environmental exposures. Logistic regression demonstrated statistically significant differences in CCI category in the exposed group versus technical group (odds ratio 1.7: 95% CI 1.3-2.0) and a blue-yellow confusion in the exposed group versus technical group (odds ratio 1.4: 95% CI 1.1-1.7). No differences were observed between the exposed group and the non-technical group.
  
  
  CONCLUSIONS
  The results indicate reduced color discrimination among the exposed subjects compared to one of two control groups. The findings may be due to previous exposure to solvents among the air force personnel.
authors.affiliation: Faculty of Health, University of Newcastle, University Drive, Callaghan, NSW 2308, Australia. maya.guest@newcastle.edu.au
authors.forename: Maya
authors.initials: M
authors.lastname: Guest
authors.forename: Catherine
authors.initials: C
authors.lastname: D'Este
authors.forename: John
authors.initials: J
authors.lastname: Attia
authors.forename: May
authors.initials: M
authors.lastname: Boggess
authors.forename: Anthony
authors.initials: A
authors.lastname: Brown
authors.forename: Meredith
authors.initials: M
authors.lastname: Tavener
authors.forename: Richard
authors.initials: R
authors.lastname: Gibson
authors.forename: Ian
authors.initials: I
authors.lastname: Gardner
authors.forename: Warren
authors.initials: W
authors.lastname: Harrex
authors.forename: James
authors.initials: J
authors.lastname: Ross
mesh_terms: D000328:Adult; D000401:Aircraft; D001315:Australia / Q000453:epidemiology; D015331:Cohort Studies; D003118:Color Perception / Q000187:drug effects*; D003117:Color Vision Defects / Q000139:chemically induced* / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D007221:Industry; D008297:Male; D008875:Middle Aged; D008889:Military Personnel; D009784:Occupational Diseases / Q000139:chemically induced* / Q000453:epidemiology / Q000503:physiopathology; D016273:Occupational Exposure / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D012997:Solvents / Q000633:toxicity*; D015351:Vision Screening
chemical_list: D012997:Solvents