Diastolic blood pressure effect of traffic-related air pollution: a trial of vehicle filtration

Traffic-related air pollutants (TRAPs) are implicated in cardiovascular disease and increases in blood pressure. We tested whether real-world commute exposures to TRAPs affect blood pressure in healthy subjects. We conducted a double-blind crossover trial, randomized to order, in which 16 young healthy participants took three 2-hr drives in heavy Seattle traffic, separated by several weeks. On two days, on-road air was entrained into the cabin through the vehicle’s factory air vents and sham filters. On a third day, the vehicle was equipped with effective filtration. Blood pressure was measured before, during, and after exposure using finger pulse waveform [Finapres] and was analyzed using mixed effects models. On filtered days in-vehicle particle count was reduced by 85%. At approximately 1 hour after drive start, diastolic blood pressure, relative to pre-drive levels, was on average 7.6mmHg higher (95% CI: 3.2, 12.0) in unfiltered drives compared to filtered drives. The effect of unfiltered air was minimal at 2 hours after drive start but then increased again post-exposure (Figure 1). The pattern for systolic blood pressure was similar. Urban traffic pollutant inhalation causes substantial changes in blood pressure in realistic conditions that occur rapidly, are sustained over 24 hours, and can be reduced with effective air filtration.
Source: European Respiratory Journal - Category: Respiratory Medicine Authors: Tags: Occupational and Environmental Health Source Type: research