This research is designed to investigate associations between coarse particulate matter (CP) mass concentrations and several health outcomes in a pair of urban and rural communities: Denver and Greeley, CO, and to characterize the particle composition and origin in both communities.

To accomplish these objectives, we are measuring the mass concentration of CP at 4 sites in Denver and 3 sites in Greeley continuously for 3 years (January 1, 2008-December 31, 2010), which will provide daily levels for the epidemiologic models and allow us to evaluate the spatial variability of CP in both locations. We also plan to measure components of CP (total and water soluble organic carbon, elemental carbon, carbohydrates, protein, endotoxin, water-soluble organic nitrogen, ionic species and metal species) in these two communities for a sample of days in the study period (50 samples at 2 sites in each community for a total of 200 samples). We will determine the response of toxicological assays for reactive oxygen species and cytotoxicity to CP from Denver and Greeley in alveolar macrophage cells. We will utilize positive matrix factorization methods to characterize the source contributions in each of the locations.

To assess and compare health outcomes in the two locations, we will evaluate the daily CP levels (and other air pollutants measured by the state of Colorado) in relation to several measures of morbidity: ventricular arrhythmic events in patients with implantable cardioverter defibrillators; cardiopulmonary emergency department visits, and adverse birth outcomes (preterm birth and intrauterine growth restriction). We will compare the estimated health effects observed in Denver and Greeley and evaluate any differences with respect to composition, spatial variability and source contributions to CP, as well as with respect to population differences.

This research will contribute to our understanding of the health outcomes associated with CP and other air pollutants in a region of the country with relatively sparse monitoring data and few prior health effects studies. The work will allow comparison of responses in urban and rural communities that are affected by distinctly different sources of CP, with major contributions from agriculture and mining activities in Greeley. Additionally, both communities have substantial Hispanic populations (~30% of the population in both locations), allowing for a potential contribution regarding the health effects in this rarely studied population.

Project Team: Dr. Michael Hannigan (PI), Dr. Jana Milford, Dr. Shelly Miller, University of Colorado, Boulder; Dr. Jennifer Peel, Colorado State University

WEBSITE: www.colorado.edu/mechanical/CRUSH