Dose Response Relations for Health Effects Caused by Office Dust

The basic procedure is an exposure experiment in which human subjects are exposed to controlled variations of dust spiked with Glucan. Their responses are monitored before, after minutes and hours of exposure and later the same evening. Two groups of subjects are selected in a pre-investigation using strict selection and exclusion criteria. The two groups are atopic persons and responders to Histamine in a RSM nasal provocation test. The groups are exposed under controlled conditions in a climate chamber at IMA to office dust spiked with Glucan (same procedure and amount as in DAMOS) at clean air level (less than 20 micro-g/m3 (TSP) and at 150, 300 and 700 micro-g/m3 (TSP). In the pre-investigation and during the exposure sessions a number of personal characteristics are measured or registered to be used in the statistical analyses as explaining variables for the responses of the subjects. The dust exposure will be characterized both though its size distribution and gravimetrically using up-to-date analytical instruments. To optimise the exposures several pilot studies are made. Only effects measures, which previously have shown clear indications of responses to dust exposures, are included in the study. The timetable includes pre-investigations, two repetitions of the exposure design (run 1 and 2), analyses of the bio-samples, statistical analyses, and reporting. The study includes a main study and several additional work-packages, which will be activated when funding become available.