Health outcome · function
Lung function
Also: FEV1, FVC, spirometry
How much air the lungs can move and how fast — measured by spirometry as forced vital capacity and forced expiratory volume in one second. Reduced lung function is the most common objective marker of harm from indoor and outdoor air pollution.
Why it matters indoors
Lung function grows through childhood, peaks in the early twenties and declines slowly thereafter. Air pollution exposure blunts the growth in children and accelerates the decline in adults; the deficit is usually a few percent, invisible day to day but associated with later respiratory and cardiovascular disease. It is the outcome that intervention studies can measure within weeks, which makes it central to evidence on air purifiers, ventilation and cooking-stove replacement.
Indoor factors with evidence
12 of 18 Findings — those with the strongest study design.
| Factor | Effect | Population | Study design | Source | Checked |
|---|---|---|---|---|---|
| Particulate matter (PM₂.₅ and PM₁₀) | SMD 0.04 (-0.07–0.15) · borderline | — | systematic review and meta-analysis of 27 randomised controlled trials of personal-level protective measures against air pollution (air purifiers, respirators and similar), GRADE-assessed | F-0237 Effectiveness of Personal‑Level Protective Measures Against … (2026) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | difference 0.2 (0.1–0.5) per 1 µg/m3 % | — · home | crossover randomised intervention in the homes of asthmatic children aged 6 to 12: portable air filtration switched on and off over seven weeks, with indoor fine particles measured continuously and peak expiratory flow rate recorded by the children | F-1613 Kim et al. Association between Peak Expiratory Flow Rate and Exposure L… (2020) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | difference 1.2 (0.1–2.7) per 1 µg/m3 % | — · home | crossover randomised intervention in the homes of asthmatic children aged 6 to 12: portable air filtration switched on and off over seven weeks, with indoor fine particles measured continuously and peak expiratory flow rate recorded by the children | F-1614 Kim et al. Association between Peak Expiratory Flow Rate and Exposure L… (2020) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | no effect size in the sentence; the same sentence reports autumn indoor exposure significantly affecting peak expiratory flow and wheezing | five patients with asthma or chronic obstructive pulmonary disease (average age 50 years, 40 % male) · city (ambient) | panel study: five patients with asthma or COPD monitored over a whole year with 24 h indoor and outdoor PM2.5 measurements, daily peak expiratory flow and biweekly symptom reports (linear mixed effect models, generalized estimating equations) | F-0089 Xydi et al. Assessing the Impact of Spatial and Temporal Variability in … (2024) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | within-group change in the intervention arm, not a between-group difference | adults aged 65 and over in a home-visit health programme · home | pilot cluster non-randomised controlled trial: 59 community-dwelling adults aged 65 and over in Incheon (intervention n = 30, control n = 29), nurse-delivered educational intervention against usual care, outcomes at baseline and 6 weeks | F-0093 Pilot study of a community-based PM2.5educational interventi… (2026) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | within-group change in the intervention arm, not a between-group difference | adults aged 65 and over in a home-visit health programme · home | pilot cluster non-randomised controlled trial: 59 community-dwelling adults aged 65 and over in Incheon (intervention n = 30, control n = 29), nurse-delivered educational intervention against usual care, outcomes at baseline and 6 weeks | F-0094 Pilot study of a community-based PM2.5educational interventi… (2026) | machine |
| Indoor plants (phytoremediation) | difference 13.9 | asthmatics and their households · home | quasi-experimental study in the homes of asthmatics in Korea over two observation terms: households of continuation kept the indoor plants for both terms, households of withdrawal kept them for the first term and passed the second without any plants; formaldehyde and benzene, toluene, ethylbenzene and xylene were measured indoors, with peak expiratory flow rate twice a day and an asthma-specific quality of life questionnaire, compared with the Mann-Whitney test | F-1225 House-plant placement for indoor air purification and health… (2014) | machine |
| Indoor plants (phytoremediation) | difference 24.7 | asthmatics and their households · home | quasi-experimental study in the homes of asthmatics in Korea over two observation terms: households of continuation kept the indoor plants for both terms, households of withdrawal kept them for the first term and passed the second without any plants; formaldehyde and benzene, toluene, ethylbenzene and xylene were measured indoors, with peak expiratory flow rate twice a day and an asthma-specific quality of life questionnaire, compared with the Mann-Whitney test | F-1226 House-plant placement for indoor air purification and health… (2014) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | RR 5.38 (2.19–13.26) | schoolchildren aged 9 to 14 · classroom | cross-sectional field study: five public primary schools in an industrialised township and one control school, PM10 and PM2.5 sampled in classrooms and outdoors over 8-hour school days in the dry and wet seasons, 578 pupils examined by questionnaire and spirometry | F-0057 Levels of PM10 and PM2.5 and Respiratory Health Impacts on S… (2020) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | RR 5.73 (2.34–14.06) | schoolchildren aged 9 to 14 · classroom | cross-sectional field study: five public primary schools in an industrialised township and one control school, PM10 and PM2.5 sampled in classrooms and outdoors over 8-hour school days in the dry and wet seasons, 578 pupils examined by questionnaire and spirometry | F-0058 Levels of PM10 and PM2.5 and Respiratory Health Impacts on S… (2020) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | OR 8.91 (3.20–30.95) | schoolchildren aged 9 to 14 · classroom | cross-sectional field study: five public primary schools in an industrialised township and one control school, PM10 and PM2.5 sampled in classrooms and outdoors over 8-hour school days in the dry and wet seasons, 578 pupils examined by questionnaire and spirometry | F-0059 Levels of PM10 and PM2.5 and Respiratory Health Impacts on S… (2020) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | OR 9.79 (3.53–33.91) | schoolchildren aged 9 to 14 · classroom | cross-sectional field study: five public primary schools in an industrialised township and one control school, PM10 and PM2.5 sampled in classrooms and outdoors over 8-hour school days in the dry and wet seasons, 578 pupils examined by questionnaire and spirometry | F-0060 Levels of PM10 and PM2.5 and Respiratory Health Impacts on S… (2020) | machine |
Each row is one Finding — a sentence as printed in one study, recorded with its page in the Coridum Knowledge Base. Follow the Finding number for the exact wording and the citation. Checked says who verified the row: machine means every automatic check passed and the surrounding text was read; person means someone read the sentence in the document. Rows are re-checked by a person over time. The studies are curated in the Coridum Knowledge Base; the reading of them together is a Claim, shown separately.
In the literature
- Lung function in volunteers before and after exposure to trichloramine in indoor pool environments and asthma in a cohort of pool workers (2012). doi:10.1136/bmjopen-2012000973 CKB 0512
- Hüls Genetic susceptibility to asthma increases the vulnerability to indoor air pollution…. The European respiratory journal. doi:10.1183/13993003.01831-2019 CKB 0557
- Effects of indoor environment and lifestyle on respiratory health of children in Chongqing, China. Journal of thoracic disease. doi:10.21037/jtd.2020.03.102 CKB 0554
Studies in the Coridum Knowledge Base in which this term is used. The definition follows standard usage in WHO, ISO and textbook sources; it is not quoted from these papers.
CKB = document number in the Coridum Knowledge Base, our curated library of peer-reviewed studies. Follow the DOI for the original paper.
Cite this page
Coridum Research. Lung function. Coridum Knowledge G-0058, 16 September 2026. https://coridum.com/k/G-0058/