Colour vision and light sensitivity in tunnel workers previously exposed to acrylamide and N-methylolacrylamide containing grouting agents.
OBJECTIVE
The aim of the study was to examine possible persisting visual system effects in tunnel workers previously exposed to acrylamide and N-methylolacrylamide during grouting work.


METHODS
Visual field light sensitivity threshold and colour vision has been examined among 44 tunnel workers 2-10 years after exposure to acrylamide and N-methylolacrylamide containing grouting agents. Forty-four tunnel workers not involved in grouting operations served as control group. Information on exposure and background variables was obtained for all participants from a questionnaire. Visual light sensitivity threshold was measured using Humphrey Visual Field Static Perimeter 740, program 30-2 Fastpack, with red stimuli on white background, and colour vision, using Lanthony D-15 Desaturated Color test. Based on D-15d test results, colour confusion index (CCI), and a severity index (C-index) was calculated.


RESULTS
The exposed group had a significantly higher threshold for detecting single stimuli in all parts of the inner 30 degrees of the visual field compared to the control group. The foveal threshold group difference was 1.4 dB (p=0.002) (mean value, both eyes). On the Lanthony 15 Hue Desaturated test, the exposed subjects made more errors in sorting blue colours, and a statistically significant increase in C-index was observed. Surrogate measures for duration and intensity of exposure gave no further improvement of the model.


CONCLUSIONS
The results indicate slightly reduced light sensitivity and reduced colour discrimination among the exposed subjects compared to the controls. The findings may be due to previous exposure to acrylamide containing grouts among the tunnel workers.
Goffeng
Lars Ole
LO
Department of Occupational Medicine and Epidemiology, National Institute of Occupational Health, P.O. Box 8149 Dep, N-0033 Oslo, Norway. lars.goffeng@stami.no
Kjuus
Helge
H
Heier
Mona Skard
MS
Alvestrand
Monica
M
Ulvestad
Bente
B
Skaug
Vidar
V
D000178:Acrylamides; D000328:Adult; D003118:Color Perception / Q000187:drug effects*; D003117:Color Vision Defects / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000139:chemically induced* / Q000150:complications*; D020795:Photophobia / Q000188:drug therapy*; D012044:Regression Analysis; D012684:Sensory Thresholds / Q000187:drug effects; D011795:Surveys and Questionnaires; D014787:Vision Tests / Q000379:methods; D014794:Visual Fields / Q000187:drug effects
D000178:Acrylamides