Quantification of traffic-related emissions and exposures at U.S.-Mexico Border Crossings using real-time mobile sensors

In-cabin air quality data will be collected using three different monitoring instruments. The pollutants analyzed in this study will be nitrogen dioxide, (NO₂), particulate matter (PM_2.5, PM₁₀), and Ozone (O₃). Ozone is an EPA regulated criteria pollutant, although not directly emitted from the vehicles but is a photochemical product involving another critical traffic pollutant, NO₂. Another set of the same three air quality monitors will be placed inside the vehicle with the inlets coming through the top of the vehicle to measure the out-cab pollutant concentrations. Air pollution measurements will be conducted during 30 drives across the POE, conducted over two weeks. Instruments will collect 1-second data during each run which is estimated to be 1-2 hours, resulting in a total of around 7200 data points per run, each run will consist of a 1-mile drive in each direction, into Mexico and back.

The study will conduct community PM air monitoring on both sides of the border. This will be implemented using low-cost PM sensors (by Purple Air Inc.) to cover a larger area and provide real-time concentrations for communities to monitor. Community monitors will help calculate differences in exposure between citizens on the POE and those in the surrounding communities.