Objective: To study the effect of occupational exposure to rubber processin
g, smoking, and alcohol drinking on lymphocyte DNA damage. Subjects and Met
hods: Of 371 employees (197 men and 174 women) from a rubber factory in Gua
ngzhou, 281 were rubber processing workers from five production sections an
d 90 were managerial workers. Information on occupational exposure, smoking
, and drinking was collected by interviews. Blood samples were taken in the
morning by venipuncture. DNA damages were measured by the Comet assay. Pos
sible DNA-protein crosslinks were broken down by proteinase K. Tail moment,
measured by Komet 4.0 image analysis software, was the measure of DNA dama
ge. Results: The rubber processing workers had larger tail moment than the
managerial workers (Geometric mean, 95%CI) [1.77 mum (1.64-1.90) versus 1.5
2 mum (1.36-1.71), P = 0.04]. Both smoking [1.93 mum (1.74-2.13) versus 1.5
9 mum (1.47-1.71), P = 0.003] and alcohol drinking [2.21 mum (1.87-2.62) ve
rsus 1.63 mum (1.53-1.74), P < 0.001] increased tail moment. Tail moment di
ffered significantly among job categories (F = 3.21, P = 0.008), the larges
t was observed in mixers. In the non-smoking and non-drinking workers, rubb
er processing workers had larger tail moment than managerial workers after
adjusting for age (P = 0.033). General linear model analysis showed that af
ter adjusting for each other, occupational exposure (P = 0.027), smoking (P
= 0.012), and alcohol drinking (P = 0.013) was associated with larger tail
moment, whereas age and gender had no effect. Conclusions: Occupational ex
posure to rubber processing, smoking, and alcohol drinking can cause DNA da
mage. (C) 2000 Elsevier Science B.V, All rights reserved.