Exposure to culturable microorganisms in paper mills and presence of symptoms associated with infections.
BACKGROUND
Previous studies of paper machine operators have to a large extent focused on endotoxins as a possible health hazard, but not culturable micro-organisms (MOs).


METHODS
Based on exposure assessment in 11 paper mills workers exposed to culturable bio-aerosols were grouped in three exposure groups. 781 exposed and 285 unexposed workers completed a questionnaire that provided data pertaining to infections and associated symptoms.


RESULTS
Concentrations of culturable bacteria in process waters varied in the range 10(4)-10(6) colony forming units (cfu)/ml, and in bio-aerosols concentrations varied typically in the range 10(4)-->10(5) cfu/m3. Operators exposed to bio-aerosols reported higher cumulative incidence of symptoms associated with infections compared to the reference population (ORs = 1.7-5.9), and the group of highest exposed workers reported higher cumulative incidence than the group of lowest exposed (ORs = 1.2-3.6).


CONCLUSIONS
Exposure to bio-aerosols containing culturable MOs may induce symptoms associated with infections among operators in paper mills.
Haug
Terje
T
Center for Occupational and Environmental Medicine, National Hospital, Oslo, N-0027 Norway. terje.haug@rikshospitalet.no
Søstrand
Per
P
Langård
Sverre
S
D000328:Adult; D000336:Aerosols; D000391:Air Microbiology; D001424:Bacterial Infections / Q000453:epidemiology*; D016022:Case-Control Studies; D018929:Cell Culture Techniques; D004269:DNA, Bacterial / Q000032:analysis; D006801:Humans; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D016273:Occupational Exposure / Q000032:analysis*; D010209:Paper; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000382:microbiology
D000336:Aerosols; D004269:DNA, Bacterial