Exposure to NO2 and PM2.5 While Commuting: Utility of Low-Cost Sensor

This study examines variations in personal exposure to PM2.5 and NO2 while commuting by bicycle, vehicle, and walking during heating and non-heating seasons in Gliwice, an industrial city in Upper Silesia, Poland. Understanding these variations is crucial for assessing health risks and developing effective mitigation strategies. Personal exposure was measured using low-cost sensors, while stationary measurements provided comparative background concentrations. The results indicate statistically significant seasonal differences in pollutant concentrations. NO2 levels were higher during the heating season (mean: 30.84 µg/m3, median: 25.60 µg/m3) than in the non-heating season (mean: 22.61 µg/m3, median: 20.37 µg/m3; p = 0.025). In contrast, PM2.5 concentrations were higher in the non-heating season (mean: 12.1 µg/m3) compared to the heating season (mean: 9.5 µg/m3; p = 0.032). Inhaled doses instead of concentrations evaluated the exposure of participants. The inhaled doses of NO2 and PM2.5 per km were significantly higher for walking (mean: 141.3 and 30.7 µg/km for the male participant; 77.9 and 31.6 µg/km for the female participant) than for bicycle and walking (p < 0.05). These findings underscore the impact of transport mode and seasonality on air pollution exposure, highlighting the necessity for targeted mitigation strategies to reduce commuters’ exposure to traffic-related pollutants.