The aim of the study is to examine inflammation in the airways and in peripheral blood, in workers in a cement plant i Norway.

OBJECTIVE: Former studies have presented conflicting data on the association between exposure to Portland cement dust and respiratory effects. Our goal is to examine inflammation in the airways and in peripheral blood in subjects exposed to cement-dust.

METHODS: All non smoking, dust exposed, workers from one department in the largest cement plant in Norway, are invited to participate. The workers will perform spirometry and induced sputum (IS) after a period of regular work with cement dust exposure, and again after a minimum of 5 days without exposure. Information on respiratory symptoms, allergy and former respiratory disease will be given on a self-reported questionnaire. IS was performed and processed as described by Pin et al. Differential cell counts will be carried out. Inflammatory markers in induced sputum and in peripheral blood will be measured. We want to use a crossover design were the cases are used as their own controls, but we will also include external controls.

Inclusion Criteria:

• Cement dust exposure
• Non-smoker or ex-smoker >3 years

Exclusion Criteria:

• Infectious disease during the last 3 weeks
• Chronic airway disease

Workers from Norways largest cement plant