The relationships between indoor environment factors and signs of eye irrit
ation were studied in a sample of female personnel with (n=112) and without
(n=64) mucous membrane symptoms working in 36 nursing departments at geria
tric hospitals in the municipality of Trondheim, Norway. The indoor climate
was characterised by high room temperature (interquartile range 23.0-23.7
degreesC), low relative air humidity (interquartile range 17-26%) and high
outdoor airflow rate, as indicated by low indoor levels of carbon dioxide (
interquartile range 490-650 ppm). An altered microbial flora was observed i
n nine of the departments, and Aspergillus fumigatus was found in three of
these. Five of the hospitals were situated in urban parts of the municipali
ty near roads with heavy traffic. In the initial analyses decreased tear-fi
lm stability (BUT) was observed in subjects working in departments with inc
reased dust settlement rate (P=0.03), in hospitals situated in urban areas
with heavy traffic (P <0.001), and in subjects working in departments with
presence of A. fumigatus (P=0.04). Increased conjunctival staining (CS) was
related to alteration of the microbial flora. In the final multivariate an
alyses statistically significant relationships were observed between BUT an
d dust settlement rate and urban vicinity of workplace and between CS and a
lteration of the microbial flora.