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Commuter Air Pollution Intervention Study

Reducing Commuter Air Pollutant Exposure by Cabin Air Filtration

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02277002
Acronym
CAPI
Enrollment
48
Registered
2014-10-28
Start date
2014-10-31
Completion date
2014-11-30
Last updated
2015-03-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Air Pollution Exposure, Cardiopulmonary Function, Cognitive Function, Lung Inflammation, Saliva Stress Hormones

Keywords

Cabin Air Filtration, Particulate Matter, Commuter Exposure, Traffic Related Air Pollution

Brief summary

Traffic related air pollution is a well-recognised and much studied contributor to smog and is linked to a number of adverse health outcomes. Although traffic pollutants can travel long distances, exposure to the highest levels of the raw emissions can occur closest to the source; e.g. in a car in dense traffic conditions. Time spent in-vehicle may contribute up to half of commuters' daily exposure to certain air pollutants. Most new cars now have or allow for a cabin air filter, but it is not known how well cabin air filtration can reduce exposure to traffic-related air pollution. This intervention study will measure commuters' exposure to air pollutants in rush hour traffic. It will evaluate the impact of this exposure on stress hormones in saliva, and short term cardiopulmonary health indicators such as blood pressure, heart rate variability and respiratory inflammation. It will also look at effects on cognition (mental processing and judgement) in this real world environment where any deficit could be important to safety. In addition, the study will examine whether cabin air filtration can reduce the exposure to traffic related air pollutants and result in improvements in short term cardiopulmonary and cognitive function. This research will contribute to our understanding of how this environment contributes to Canadians' overall air pollution exposure as well as the potential health impacts. It will also test a potentially valuable and economical means of reducing exposure to traffic related air pollution in a commuting environment. The study may also guide the future implementation of the use of cabin filters as an exposure reduction intervention. Overall Project Objectives: Can cabin air filtration effectively reduce exposure to traffic related air pollution? Does commuter exposure to air pollution affect short term stress, and cardiopulmonary and cognitive function? Can cabin air filtration mitigate the health effects of commuters' exposure to air pollution?

Interventions

DEVICECabin Air Filtration
OTHERPlacebo

No Cabin Air Filtration

Sponsors

Health Canada
Lead SponsorOTHER_GOV

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
DOUBLE (Subject, Caregiver)

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes

Inclusion criteria

* Healthy Individuals; * non-smoking.

Exclusion criteria

* Smokers; * living in a smoking household; * currently experiencing seasonal allergies; * suffering from heart rhythm problems or heart conditions; * regularly taking corticosteroid medication; * pregnant or breastfeeding; * allergic to latex; * sensitivity to adhesives

Design outcomes

Primary

MeasureTime frameDescription
Variation in cardiopulmonary function5 hoursHeart Rate Variability (HRV) will be measured from continuous ambulatory electrocardiogram (ECG) recordings collected during the study protocol. ECG will be worn for the duration of the study day period (approximately 5 hours), including a period prior to exposure and following exposure.

Secondary

MeasureTime frameDescription
Changes in neuropsychological Function5 hoursAssessment of neuropsychological function can be achieved using a battery of mood and cognitive tests. The study will use a battery of tests that are comercially available through CANTAB, the mini-mental state exam designed by University of Cambridge. Battery will be administered before and after exposure.
Changes in endothelial function5 hoursEndothelial function will be assessed using the non-invasive, FDA approved Endo-Pat2000 instrument. Test administration involves continuous measurement of blood flow and vascular tone in the fingertips of both index fingers, before, during and after an occlusion of blood flow to the non-dominant hand. Blood flow is occluded using a standard blood pressure cuff positioned on the upper arm. Measures will be carried out before and after exposure.
Changes in levels of Hypothalamic-Pituitary-Adrenal (HPA) Axis5 hoursIn the present study, salivary cortisol will be assessed as a non-invasive measure of HPA axis activation. Saliva sample collection will be done with Salivette swabs twice before exposure, once during exposure and twice following exposure.
Fraction of Exhaled Nitric Oxyde5 hoursLung inflammation will be assessed as the fraction of nitric oxide (NO) exhaled in the participants' breath using a portable, FDA approved, fractional exhaled nitric oxide (FENO) measurement device, the NIOX Mino. Measures will be carried out before and after exposure.

Countries

Canada

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026