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Active, not recruitingNCT05016271Updated Sep 2, 2026

Health Benefits of Air Purifiers in Primary School Students

An interventional study of Air purifier and fresh air ventilation systems with high-efficiency particulate air (HEPA) filters and Air purifier and fresh air ventilation systems without high-efficiency particulate air (HEPA) filters in Cardiopulmonary Function and Child, sponsored by Fudan University. Active, not recruiting at 1 site in China. Open to participants aged 8 Years to 12 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-02.

Sponsored by Fudan University · Not applicable, Interventional, and Prevention

Phase
Not applicable
Study type
Interventional
Enrollment
110
Allocation
Randomized
Ages
8 Years to 12 Years
Sex
All
01

Study summary

This study aims to explore changes in cardiopulmonary function and other health indicators in primary school students with the intervention of air purifiers on a randomized controlled trial.

Read the detailed description

The investigators will conduct a randomized controlled trial among 110 healthy children in Jiaozuo city, Henan, China. The eligible children will be divided into two groups according to their classes and randomly receive interventions of either true or sham air purifiers. The air purifiers devices in classroom [air purifiers and fresh air ventilation systems] will operate during the school time and the devices in bedrooms (air purifiers) operate during the home time in the intervention period. All the participants and investigators will be blinded to the group assignment. Epidemiological questionnaires (i.e., basic characteristics, eating habits, daily schedule, etc.) will be conducted and health indicators (i.e., blood pressure, pulmonary function indicators, fractional exhaled nitric oxide, and fractional exhaled carbon monoxide) and biological specimens (i.e., morning urine, venous blood, exhaled breath condensate, and feces) will be evaluated and collected at baseline and after the completion of intervention period (4 months anticipated).

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Conditions studied

  • Cardiopulmonary Function
  • Child

Keywords

  • Air pollution
  • Particulate matter
  • Air Purifiers
  • Cardiopulmonary system
03

In context

Lead sponsor

Fudan University is the lead sponsor of 1,270 studies on the registry; 623 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
8 Years to 12 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Age of between 8 and 12 years old
  • Males and female of ethnic Han
  • Subjects who have no plans to change classroom during the intervention period
  • Subjects who staying in Jiaozuo city during the intervention period

Exclusion criteria

Exclusion Criteria:

  • Subjects with asthma, childhood diabetes, childhood hypertension, and behavioral disorders
  • Subjects who plan to transfer or move offsite within six months
  • Subjects who decorated or plan to decorate home within six months
  • Subjects with smokers in the household
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Study design

Phase
Not applicable
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Investigator)
Enrollment
110 participants (estimated)

Study arms

  • Experimental
    True air purifier group

    Children in this group will receive an intervention of air purifiers with high-efficiency particulate air (HEPA) filters.

    Behavioral: Air purifier and fresh air ventilation systems with high-efficiency particulate air (HEPA) filters

  • Sham comparator
    Sham air purifier group

    Children in this group will receive an intervention of air purifiers without high-efficiency particulate air (HEPA) filters.

    Behavioral: Air purifier and fresh air ventilation systems without high-efficiency particulate air (HEPA) filters

Interventions

  • BehavioralAir purifier and fresh air ventilation systems with high-efficiency particulate air (HEPA) filters

    This group will receive an intervention of true air purifiers. The air purifiers in classroom (air purifiers and fresh air ventilation systems with HEPA filters) will operate during the school time and the air purifiers in bedrooms (air purifiers with HEPA filters) operate during the home time in the intervention period (4 months anticipated).

  • BehavioralAir purifier and fresh air ventilation systems without high-efficiency particulate air (HEPA) filters

    This group will receive an intervention of sham air purifiers. The air purifiers in classroom (air purifiers and fresh air ventilation systems without HEPA filters) will operate during the school time and the air purifiers in bedrooms (air purifiers without HEPA filters) operate during the home time in the intervention period (4 months anticipated).

06

What researchers measure

Primary outcomes

  1. Changes of heart rate variability

    Nihon Kohden Electrocardiograph and Carepatch Electrocardiogram are used to measure heart rate variability, including standard deviation of all normal-to-normal R-R intervals (SDNN), standard deviation of sequential five-minute R-R interval means (SDANN), root-mean-square difference of successive normal R-R intervals (RMSSD), low frequency (LF), and high frequency (HF) in intervention and control groups. To eliminate possible errors, measurements are conducted by the same trained staff using the same instrument.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  2. Changes of forced expiratory volume in 1 s (FEV1)

    The pulmonary function measures are performed by the professional medical device. Before the pulmonary function test, subjects practice several times with the guidance of professional staff. During the examination, each subject in a sitting position and clamp the nose clip, and repeat the test, with the best result as the criterion.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  3. Changes of forced vital capacity (FVC)

    The pulmonary function measures are performed by the professional medical device. Before the pulmonary function test, subjects practice several times with the guidance of professional staff. During the examination, each subject in a sitting position and clamp the nose clip, and repeat the test, with the best result as the criterion.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  4. Changes of forced expiratory volume in 1 s (FEV1) / forced vital capacity (FVC) ratio

    The pulmonary function measures are performed by the professional medical device. Before the pulmonary function test, subjects practice several times with the guidance of professional staff. During the examination, each subject in a sitting position and clamp the nose clip, and repeat the test, with the best result as the criterion.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  5. Changes of peak expiratory flow (PEF)

    The pulmonary function measures are performed by the professional medical device. Before the pulmonary function test, subjects practice several times with the guidance of professional staff. During the examination, each subject in a sitting position and clamp the nose clip, and repeat the test, with the best result as the criterion.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  6. Changes of fractional exhaled nitric oxide (FeNO) levels

    A NIOX VERO Sensor is used to measure fractional exhaled nitric oxide (FeNO) as a biomarker for airway inflammation. After deep breathing, the subjects gently inhaled into the device. The instrument shows FeNO level of the subjects.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  7. Changes of fractional exhaled carbon monoxide (FeCO) levels

    Use PICO to measure fractional exhaled carbon monoxide (FeCO) as a biomarker for cardiovascular risk. After deep breathing and holding the breath for 15 seconds, the subjects gently inhaled into the device. The instrument shows FeCO level of the subjects.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  8. Changes of blood pressure

    Using Omron blood pressure monitor to measure the systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure for each subject by the trained staff using the same instrument.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

Secondary outcomes

  1. Changes of C-reactive protein (CRP)

    Detect the concentration of C-reactive protein (CRP) in blood sample to examine the different level of inflammation between the groups of intervention and control.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  2. Changes of 8-hydroxydeoxyguanosine (8-OHdG)

    Detect the concentration of 8-hydroxydeoxyguanosine (8-OHdG) in urine sample of groups of intervention and control. 8-OHdG is a biomarker for DNA oxidative damage.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  3. Changes of persistent response (PR)

    Examine persistent response (PR) as the index to test the focus ability of children. The test is performed by the Wisconsin Card Sorting Test (WCST) through a computer, and the index reflects the ability of cognitive transfer. The normal value is less than or equal to 27.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

  4. Differences in metabolite levels detected in metabolomics between groups of intervention and control.

    Mass spectrometry-based serum metabolomics is non-targeted. The study is to explore the differential metabolites in blood/urine/exhaled breath condensate (EBC) samples of the groups of intervention and control.

    Time frame: Baseline and after the completion of intervention period (4 months anticipated)

07

Study locations

1 site
  • Department of Environmental Health, School of Public Health, Fudan University
    Shanghai, Shanghai Municipality 200032, China
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References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 2, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT05016271
Lead sponsor
Fudan University
Responsible party
Haidong Kan (Professor, Fudan University) — Principal investigator
First posted
Aug 23, 2021
Start date
Sep 22, 2021
Primary completion
Jun 30, 2022
Completion
Dec 31, 2026 (estimated)
Last update
Sep 2, 2026

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is active, not recruiting, as verified in Feb 2026. You cannot join it, but the record below documents what was studied.

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