The pilot project was focused on obtaining preliminary data to highlight the tremendous potential of using the renowned Arizona Respiratory Center (ARC) cohorts for NIEHS-funded air pollution epidemiology projects. More specifically, this pilot project allowed us to demonstrate access to exclusive historical air pollution data as well as demonstrate our capabilities to measure air pollutants in order to develop land-use regression (LUR) models for exposure assessment.  This will be completed through the following objectives: 1) measure nitrogen oxides (NOx) and particulate matter (PM) throughout the Tucson area in 2015-2016; 2) resurrect historical NOx and PM measurements collected throughout the Tucson area in 1986-1987; 3) develop models and resulting maps of NOx and PM concentrations; 4) assess relationships between these historical exposures and health outcomes in the Children’s Respiratory Study (CRS); and 5) prepare a NIEHS R21 proposal. Completion of this pilot project and the R21 proposal can allow us to establish our capabilities in LUR exposure assessment and presents future opportunities to propose other projects to NIEHS.