To study the indoor climate, the psychosocial work environment and occupants' symptoms in offices a cross-sectional questionnaire survey was made in 11 naturally and 11 mechanically ventilated office buildings. Nine of the buildings had mainly cellular offices; five of the buildings had mainly open-plan offices, whereas eight buildings had a mixture of cellular, multi-person and open-plan offices. A total of 2301 occupants, corresponding to a response rate of 72%, completed a retrospective questionnaire. The questionnaire comprised questions concerning environmental perceptions, mucous membrane irritation, skin irritation, central nervous system (CNS) symptoms and psychosocial factors. Occupants in open-plan offices are more likely to perceive thermal discomfort, poor air quality and noise and they more frequently complain about CNS and mucous membrane symptoms than occupants in multi-person and cellular offices. The association between psychosocial factors and office size was weak. Open-plan offices may not be suited for all job types. PRACTICAL IMPLICATION: Open-plan offices may be a risk factor for adverse environmental perceptions and symptoms.

This study was undertaken to investigate how the length of the extraction period influences the (1 ? 3)-b-D-glucan (b-glucan) yield and also to examine the background concentration of b-glucan as airborne b-glucan in outdoor environments in different seasons and as concentrations in airborne and floor dust in offices. To ensure compatibility between results obtained in different laboratories, it is important to use optimal and standardised methods to extract and quantify b-glucan. In this study, an extraction period of 60 min gave the highest b-glucan yield. The median concentration of b-glucan in 44 floor dust samples was 597 lg g -1 dust. The median concentration of airborne b-glucan in offices was 5.1 ng m -3 in the summer and 2.3 ng m -3 in the winter, and the outdoor median concentration in towns was 6.8 ng m -3 . The outdoor airborne concentration of b-glucan was significantly lower in January, November and December than during the rest of year. In July, the median airborne concentration of b-glucan was 14 times higher than in January. Furthermore, the airborne concentration of b-glucan was significantly higher in July than in March, April, May, September and October. In the summertime, we found that the indoor airborne concentration of b-glucan was lower than outdoor concentrations. This is in accordance with measurements of concentrations of airborne pollen and culturable fungal spores showing higher outdoor than indoor concentrations during the summer months.

Aims: To test whether the inflammatory potential of dust samples might be used to differentiate schools with high and low prevalence of building related symptoms (BRS) among the occupants. Methods: Ten schools with high prevalence of BRS and 10 schools with low prevalence were selected. Dust collected from floors, horizontal surfaces, and exhaust outlets was tested at five concentrations on the lung epithelial cell line A549. The potency of the dust (PF) to stimulate IL-8 secretion was calculated from the initial linear part of the dose-response curves. The organic fraction of the dust samples was determined by incineration. Results: The schools with low prevalence of symptoms had a BRS% of 4.4-11.0 and the schools with high prevalence a BRS% of 19.6-31.9. The PF of floor dust and surface dust correlated, and the PF was associated with the organic content of the dust. The schools with low prevalence of symptoms had a significantly lower PF than the schools with high prevalence. Using the cut point value of 4.5 ng IL-8/mg floor dust, significantly more high prevalence schools were found above the cut point than below. Conclusion: The PF of the floor dust samples correlated significantly with the prevalence of symptoms in the schools. The content of endotoxin and microorganisms did not seem to explain the inflammatory potential of the dust or BRS, and the substances in the dust causing the inflammatory potential are presently unknown. N on-specific symptoms such as mucous membrane irritations in the eyes, nose, and the upper respiratory tract, cough, dryness of the skin, and symptoms such as headache, dizziness, fatigue and lethargy, and lack of concentration, have all been related to the quality of the indoor air or the indoor environment in non-industrial buildings like offices, schools etc.

Persistent wheeze in childhood is associated with airway inflammation. The present study investigated relationships between polymorphisms in inflammatory genes, exposure to tobacco smoke and furred pets and risk of recurrent wheeze in children. Within a birth cohort of 101,042 children we identified 1111 eighteen month old cases with recurrent wheeze and 735 wheeze-free controls among 11942 children recruited in the Copenhagen area. Polymorphisms in IL-4R, IL-8, IL-13, SPINK5, and CD14 were genotyped. Interviews at gestational wks 12 and 30, and at age 6 and 18 months included questions on number of episodes with wheeze (18 months), exposure to tobacco smoke and pet-keeping. Recurrent wheeze was defined as at least four episodes of wheeze before the child was 18 months old. There was a statistically significant association between the IL-13 Arg144Gln polymorphism and risk of recurrent wheeze (p = 0.01). Furthermore, there was a statistically significant interaction between this polymorphism and exposure to tobacco smoke during pregnancy, though this was probably a chance finding. There were no other statistically significant effects of the polymorphisms or interactions with exposure to tobacco smoke in relation to the risk of recurrent wheeze. Polymorphisms in IL-8 affected the association between pet-keeping and risk of wheeze. Polymorphisms in inflammation genes might affect the association between environmental exposures and risk of recurrent wheeze in early childhood.

No abstract