Exposure, symptoms and airway inflammation among sewage workers

The purpose of the study was to determine the associations between dust,
endotoxins and bacterial exposure, and health effects in sewage workers. Exposure of
19 workers handling dry sludge and 25 other sewage workers was measured. Controls
were office workers from compost and sewage plants. Spirometry, acoustic rhinometry
and nitric oxide in exhaled air were performed before and after exposure were measured.
CRP was measured in blood samples. It was found that workers handling dry sludge
were exposed to higher levels of dust and endotoxins than other workers and reported
more airway and systemic symptoms than controls. Compared to controls, FEV1
/FVC
was 0.12 lower in workers handling dry sludge and 0.05 lower in other sewage workers. Nose irritation, cough and headache were more prevalent in workers handling dry
sludge (ORs 2.3–23), and together with unusual tiredness associated with endotoxins
and/or dust, ORs 2.9–34 for-10-fold increases in exposure. Cross-shift decreases of nasal
dimensions were larger in workers handling dry sludge than controls and were associated
with dust and endotoxin exposure. It was concluded that workers handling dry sludge
were higher exposed to endotoxins and dust than other sewage workers and also reported
more respiratory and systemic symptoms. Exposure-response relationships were [...]