A Crossover Study of In-Vehicle Air Filtration and Acute Changes in Heart Rate Variability and Cognition Among Healthy Adults

摘要

Background: 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. Methods: We measured commuters' exposure to air pollutants in rush hour traffic, and evaluated whether this exposure could be reduced by cabin air filtration. Also, we looked at effects of commuting during rush hour on heart health (i.e. heart rate variability), and cognition (using a computer-based cognitive assessment) in an environment where any deficit could be important to safety. We examined whether cabin air filtration using an electrostatic filter reduced exposure to traffic-related air pollutants and improved short term heart and cognitive function. Results: Preliminary results show that participants' heart rate variability and cognitive function were impacted by in-vehicle air pollution exposures. Cabin air filtration reduced in-vehicle particulate exposures by approximately one third. In-vehicle pollutant concentrations were notably elevated in tunnels. Conclusions: While commuting, Canadians are exposed to air pollutants that may have a measurable impact on their health. It may be possible to reduce in-vehicle exposures by installing an electrostatic air filter. Relevance: This study provides information about a potentially valuable and economical means of reducing exposure to traffic-related air pollution during daily commutes. This study also examined the impacts of air pollution exposure on cognition, an area of growing concern.