Mobile monitoring of particle number concentration and other traffic-related air pollutants in a near-highway neighborhood over the course of a year

► Mobile monitoring was performed on 55 days throughout one year. ► Hourly, daily, and seasonal variations were observed. ► Distance-decay gradients were highly dependent on traffic and meteorology. ► Annual median PNC 0-50 m from the highway was two-fold higher than background. ► Temporal variations in PNC were similar to spatial variations.