Pulmonary Function
Conditions
Brief summary
This is a randomized controlled human exposure crossover study. Investigators aim to investigate the acute health effects of ozone exposure in healthy young adults.
Detailed description
The investigators will conduct a randomized controlled human exposure crossover study among 32 healthy young adults in Shanghai, China. Each subject will be exposed twice: once to clean air and once to 200 ppb ozone in a chamber for 2 hours. During the 2-hour exposure, each subject will be requested to alternate 20 minutes of rest and 10 minutes of exercise on a treadmill. The exercise workload will be adjusted to achieve the targeted ventilation of 25 \ 27 L/min(approximately equal to 15 \ 18L/min/m2 body surface area). Ozone will be generated by a silent electric discharge method (HTU-500, AZCO Industries Ltd., Canada) and introduced into the chamber. The temperature and relative humidity in the chamber will be maintained at 22±1℃ and 55%±5%, respectively. Health examinations will be conducted immediately prior to exposure, immediately after exposure, 2 hours after exposure and again the next morning. Health examinations include symptom questionnaire, skin tests, spirometry, and Holter monitoring. We plan to collect blood, buccal, urine, nasal secretion, saliva, exhaled breath condensate, sebum, and D-squame samples.
Interventions
OTHER200 ppb ozone group
The exposure group will be exposed to 200 ppb ozone in a chamber for 2 hours while alternating 20-min rest and 10-min exercise periods. The exercise workload will be adjusted to achieve the targeted ventilation of 25 \ 27 L/min(approximately equal to 15 \ 18L/min/m2 body surface area). The temperature and relative humidity in the chamber will be maintained at 22±1℃ and 55%±5%, respectively.
OTHER0 ppb ozone group
The control group will be exposed to 0 ppb ozone in a chamber for 2 hours while alternating 20-min rest and 10-min exercise periods. The exercise workload will be adjusted to achieve the targeted ventilation of 25 \ 27 L/min(approximately equal to 15 \ 18L/min/m2 body surface area). The temperature and relative humidity in the chamber will be maintained at 22±1℃ and 55%±5%, respectively.
Sponsors
Fudan University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* Living in Shanghai during study period; * Ability to complete the exercise to achieve the ventilation of 15 to 18 L/min/m2 body surface area; * Body mass index \>18.5 and ≤30.0 (30 is the lower limit for class 2 obesity for Chinese).
Exclusion criteria
* Smoking and alcohol abuse; * Current drug and dietary supplements intake; * Subjects with allergic diseases, such as allergic rhinitis, allergic asthma, and atopy; * Subjects with cardiovascular diseases, such as congenital heart disease, pulmonary heart disease, and hypertension; * Subjects with respiratory diseases, such as asthma, chronic bronchitis, and chronic obstructive pulmonary disease; * Subjects with chronic diseases, such as diabetes, chronic hepatitis, and kidney disease; * Subjects who have a history of major surgery; * Abnormal spirometry (FEV1 and FVC ≤ 75% of predicted and FEV1/FVC ≤ 0.65); * Abnormal baseline 12-lead resting electrocardiogram; * Abnormal blood index, such as cell counting, blood lipids, and glutamic-pyruvic transaminase (GPT).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes of FEV1 | FEV1 will be examined immediately prior to exposure, immediately after exposure, 2 hours after exposure and again the next morning | Changes of forced expiratory volume in 1 second |
| Changes of FVC | FVC will be examined immediately prior to exposure, immediately after exposure, 2 hours after exposure and again the next morning | Changes of forced vital capacity |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| HRV | Holter monitoring will be performed continuously for 24 hours. | Heart rate variability |
Other
| Measure | Time frame | Description |
|---|---|---|
| Difference in adrenaline concentrations between the two exposures | 2 hours after the completion of exposure. | Difference in the serum concentrations of adrenaline between ozone exposure and filtered air exposure |
| Difference in noradrenaline concentrations between the two exposures | 2 hours after the completion of exposure. | Difference in the serum concentrations of noradrenaline between ozone exposure and filtered air exposure |
| Change in the amount of skin moisture | Immediately before exposure, 0.5 hours after the completion of exposure, and next morning. | Change in the amount of skin moisture, which was measure by a moisture meter. The number on the meter indicates how hydrated (or dehydrated) your skin is. |
| Change in L-values | Immediately before exposure, 0.5 hours after the completion of exposure, and next morning. | Change in skin color indicated by L-values, which was measured by a skin colorimeter. |
| Change in a-values | Immediately before exposure, 0.5 hours after the completion of exposure, and next morning. | Change in skin color indicated by a-values, which was measured by a skin colorimeter. |
| Change in b-values | Immediately before exposure, 0.5 hours after the completion of exposure, and next morning. | Change in skin color indicated by b-values, which was measured by a skin colorimeter. |
| Difference in CRF concentrations between the two exposures | 2 hours after the completion of exposure. | Difference in the serum concentrations of corticotrophin releasing factor between ozone exposure and filtered air exposure |
| Change in CC16 concentrations | Immediately before exposure, 2 hours after the completion of exposure, and next morning | Change in the serum concentrations of club cell protein |
| Differences in metabolite levels detected in serum metabolomics between the two exposures | 2 hours after the completion of exposure | Mass spectrometry-based serum metabolomics is non-targeted.The study is to find the differential metabolites in serum between ozone exposure and filtered air exposure. |
| Differences in metabolite levels detected in airway metabolomics between the two exposures | 2 hours after the completion of exposure | Mass spectrometry-based metabolomics in exhaled breath condensate is non-targeted.The study is to find the differential metabolites in airway between ozone exposure and filtered air exposure. |
| Differences in metabolite levels detected in urine metabolomics between the two exposures | Immediately after the completion of exposure | Mass spectrometry-based urine metabolomics is non-targeted.The study is to find the differential metabolites in urine between ozone exposure and filtered air exposure. |
| Differences in RNA expression levels detected in transcriptomics between the two exposures | 2 hours after the completion of exposure | Illumina-based transcriptomics is non-targeted. The study is to find the differentially expressed RNA between ozone exposure and filtered air exposure. |
| Differences in protein levels detected in serum proteomics between the two exposures | 2 hours after the completion of exposure | Mass spectrometry-based proteomics in serum is non-targeted. The study is to find the differentially expressed proteins in serum between ozone exposure and filtered air exposure. |
| Difference in alpha diversity of microbiota between the two exposures | Immediately after the completion of exposure | Difference in alpha diversity of microbiota in nasal secretions between ozone exposure and filtered air exposure |
| Difference in ACTH concentrations between the two exposures | 2 hours after the completion of exposure. | Difference in the serum concentrations of adrenocorticotropic hormone between ozone exposure and filtered air exposure |
| Difference in cortisol concentrations between the two exposures | 2 hours after the completion of exposure | Difference in the serum concentrations of cortisol between ozone exposure and filtered air exposure |
Countries
China
Outcome results
None listed