Controlled Human Exposure to Indoor Air, Dust and Ozone
Controlled Human Exposure to Indoor Air, Dust and Ozone
The aim of the study is to provide information which may help to improve the quality of the
 life of persons exposed to indoor environments in Danish dwellings.

 The experiment will document if dust and ozone contribute to deterioration of indoor air
 quality and to the occurrence of symptoms and health effects.

 The study is aimed at testing the hypothesis that the presence of ozone potentiate the health
 and comfort effects of dust exposure in the indoor environment.

 Testing this hypothesis will be based on the following questions:

 Does house dust and ozone in concentrations frequently encountered in Danish dwellings cause
 unwanted health effects either by themselves or by interaction?

 If so, does the presence of ozone potentiate the expected irritative effects of dust?

 The challenge of these hypotheses will be made as a controlled experiment on humans in a
 climate chamber under controlled exposure conditions.

 This controlled human experiment should be able to substantiate the findings from the
 intervention studies.

 Furthermore, they ideally reflect something relevant to the general public and therefore
 should have maximum public appeal and application possibilities.
This study is a part of a broader research programme established by CISBO ( Centre for Indoor
 air and Health in Dwellings). The purpose of the centre is to increase the general knowledge
 and to provide information on indoor air quality and related Health effects. The study may
 contribute with basic information on underlying pathophysiological mechanisms involved in
 human responses to these pollutants and in their interactive effects. The study includes as
 methods and techniques to detect minor changes in biomarkers suggesting early effect of
 exposure. These analyses will give information at a high sensitive level about the exposure
 effects on biomarkers for an array of symptoms and reactions.

 The study Group consitss of 24 non-smoking persons(aged 60-70). A controlled, randomized and
 balanced Latin square cross-over design using the participants as their own controls. The
 exposures are arranged in a full-scale climate chamber where the participants will be exposed
 for 5½ hour under controlled environmental conditions.

 The exposure facility (Climate chamber):

 The exposures are arranged at the controlled experimental facilities at our department which
 include climate chambers and exposure generators for dust and ozone. The exposure sessions
 will take place under controlled conditions in a 79 m3 climate chamber made of welded
 stainless steel optimized for experiments with gasses and particulate air pollutants. The
 chamber facility allows exposures with controlled ventilation, temperature and air humidity
 and has an efficient mixing of ventilation air with the chamber air.

 All participants will attend all four diff. exposure sessions:

 Dust (250-300µg/m3), Ozone (0,1ppm ozone),Dust+ozone (250-300µg/m3 + 0,1 ppm ozone), Filtered
 air (<20µg/m3). with at least 2 weeks between each exposure session to eliminate hang-over
 effects. The filtered air and dust and ozone contaminated sessions will be identical except
 for the air quality. The exposures are unknown to the participants and staff to keep the
 study double blinded. The blinding will be continued until the basic statistical analyses
 have been conducted.

 Selected subjective and objective health outcomes are measured at baseline and at follow-up
 at predefined time points.

 Health assessment and Measurements includes:

 Subjective symptoms, Respiratory outcomes (lung function, FENO, exhaled breath condensate,
 nasal lavages, Acoustic Rhinometri) Blood samples (inflammation biomarkers)
Inclusion Criteria:

 -  Non-smoker

 -  Normal lung function

 -  No active allergic rhinitis

 -  Be free from clinically significant cardiac, pulmonary, neurological and psychiatric
 disease as determined by medical history, physical examination and screening
 investigations.

 -  With no clinically-significant deviation outside the normal ranges for blood presure
 and pulse Measurements.

 -  Capable of giving informed consent

 -  Be avaible to complete the study

 -  Provide oral and written informed consent to participate in the study

 Exclusion Criteria:

 -  Atopy

 -  Upper respiratory tract infection within 2 weeks

 -  Medical conditions likely to affect the outcome of the study in the opion of the
 investigator.

 -  Presence of any respiratory disease

 -  Infection of the upper Airways/lower Airways includingviral infections in the 14 days
 prior to screening and at the start of/or during the study.