Commuter Air Pollution Intervention Study (CAPI)
|ClinicalTrials.gov Identifier: NCT02277002|
Recruitment Status : Completed
First Posted : October 28, 2014
Last Update Posted : March 2, 2015
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?
|Condition or disease||Intervention/treatment||Phase|
|Cognitive Function Cardiopulmonary Function Saliva Stress Hormones Air Pollution Exposure Lung Inflammation||Device: Cabin Air Filtration Other: Placebo||Not Applicable|
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||48 participants|
|Intervention Model:||Crossover Assignment|
|Masking:||Double (Participant, Care Provider)|
|Official Title:||Reducing Commuter Air Pollutant Exposure by Cabin Air Filtration|
|Study Start Date :||October 2014|
|Actual Primary Completion Date :||November 2014|
|Actual Study Completion Date :||November 2014|
Placebo Comparator: Placebo
Participants are exposed to unfiltered cabin air
No Cabin Air Filtration
Active Comparator: Cabin Air Filter
Participants are exposed to filtered cabin air
Device: Cabin Air Filtration
- Variation in cardiopulmonary function [ Time Frame: 5 hours ]Heart 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.
- Changes in neuropsychological Function [ Time Frame: 5 hours ]Assessment 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 function [ Time Frame: 5 hours ]Endothelial 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) Axis [ Time Frame: 5 hours ]In 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 Oxyde [ Time Frame: 5 hours ]Lung 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.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02277002
|Montreal, Quebec, Canada|
|Principal Investigator:||Gary Mallach||Health Canada|