Impairment of colour vision in aircraft maintenance workers

In the present study, the authors examined possible persisting effects to colour 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 Colour vision was tested in 512 exposed personnel, 458 technical-trade comparisons, and 330 nontechnical comparisons using the Ishihara test plates and the Lanthony D-15 Desaturated Colour disk arrangement test. Participants were excluded if they failed the Ishihara test as this indicates congenital colour blindness. From the Lanthony results, the type of colour deficient vision (CDV) was diagnosed, and additional, the Bowman’s colour confusion index (CCI) was calculated Regression models were used to examine whether there was an association between colour vision deficiencies and F-111 fuel tank maintenance, adjusting for possible confounders. 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 vs. tech. group (odds ratio 1.7: 95% CI 1.3-2.0) and a blue-yellow confusion in the exposed group vs. technical group (odds ratio 1.4: 95% CI 1.1-1.7). No differences were observed between the exposed group and the nontechnical group. The results indicate reduced colour discrimination among the exposed subjects compared to one of two control groups. The authors concluded that the results from this study may be due to previous exposure to solvents among the air force personnel.

Authors: Guest, Maya; D’Este, Catherine; Attia, John; Boggess, May; Brown, Anthony; Tavener, Meredith; Gibson, Richard; Gardner, Ian; Harrex, Warren; Ross, James ;Full Source: International Archives of Occupational and Environmental Health [fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][online computer file] 2011, 84(7), 723-733 (Eng) ;