A growing number of epidemiological studies conducted worldwide suggest an increase in the occurrence of adverse health effects in populations living, working, or going to school near major roadway...

In February 2015, the United States Environmental Protection Agency (EPA) sponsored a workshop in Research Triangle Park, NC, USA to review the current state of the science one missions, air quality impacts, and health effects associated with exposures to ultrafine particles[1].

The growing number of health studies identifying adverse health effects for populations spending significant amounts of time near large roadways has increased the interest in monitoring air quality in this microenvironment. Designing near-road air monitoring networks or interpreting previously collected near-road monitoring data is essential for transportation system planning, environmental impact assessments, and exposure assessments in health studies. For these applications, care must be taken in determining the pollutants of interest for both air quality and health assessments. In addition, planners and data analysts need to evaluate and understand the potential influence of the roadway type, design, and presence of roadside structures on the potential transport and dispersion of traffic-emitted pollutants on these air quality and health evaluations. This paper summarizes key factors related to the collection and interpretation of near-road air quality data from the perspective of the pollutants of interest and the location of the monitoring sites.