2010 Progress Report: Health Effects and Characterization of Urban and Rural Coarse ParticulateMatter in Northeastern ColoradoEPA Grant Number: R833744
Title: Health Effects and Characterization of Urban and Rural Coarse ParticulateMatter in Northeastern Colorado
Investigators: Hannigan, Michael P. , Milford, Jana B. , Miller, Shelly , Navidi, William C.
Current Investigators: Hannigan, Michael P. , Milford, Jana B. , Miller, Shelly , Navidi, William C. , Peel, Jennifer
Institution: University of Colorado at Boulder , Colorado School of Mines , Colorado State University
EPA Project Officer: Chung, Serena
Project Period: January 1, 2008 through December 31, 2012 (Extended to June 30, 2013)
Project Period Covered by this Report: January 1, 2010 through December 31,2010
Project Amount: $1,200,000
RFA: Sources, Composition, and Health Effects of Coarse Particulate Matter (2006) RFA Text | Recipients Lists
Research Category: Air , Air Quality and Air Toxics , Particulate Matter
The proposed research is designed to investigate associations between coarse particulate matter (PM10-2.5) 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.
During the third year, we were focused on data collection. At the core, CRUSH is a time-series population epidemiology study comparing rural effects to urban effects with some coarse PM characterization efforts added on to help inform any differences observed. As such, until the end of the project, our progress reports focus in on collection of PM concentration measurements and health effect measurements. The third year of this study typifies this situation as we spent most of our time collecting data.
Continuous Mass Concentration Results. As of the close of 2010, we have collected 2 years of hourly PM10-2.5 and PM2.5 mass concentrations at two locations in Denver and one location in Greeley. The same information was collected for one year at a second location in Greeley but the strong correlation between the two Greeley sites allowed us to stop collection of measurements at the second site – and conserve measurement resources. For the three sites, we have greater than 85% coverage, or, in other words, less than 15% down time. We submitted a manuscript describing the first year of this data, demonstrating temporal trends as well as correlations across space and PM size. These results were initially described in the previous progress report.
Characterization via Filter Sample Collection. To characterize PM10-2.5 and PM2.5, we created four filter samplers to allow us to explore spatial variability of the chemical species within both Denver and Greeley. The design and validation of those dichotomous virtual impactors was described in the previous progress report. We deployed those four filter samplers at the same locations where we deployed the continuous PM mass concentration measurement tools. We operate those filter samplers for 24 hours every 6th day as per the EPA regulatory air quality calendar. We started the network in Feb/March of 2010 and plan to run for one year. To date, we have analyzed the filters for mass as well as organic/elemental carbon. The figure below shows the spatial variability of the organic carbon components. The OC concentration is shown for site pairs, where each data point represents a sampling day with the x-value the concentration at one site in that city and the y-value the concentration at the other site in that city. The left two plots show the PM2.5 mass concentration data and the right sows the PM10-2.5 mass concentration data. The upper two plots show the Denver PM data and the lower two show the Greeley PM data. In all cases there is solid correlation between the OC concentrations at the two sites from the same city. In fact, the correlation coefficient is the same for both cities and both sizes; likely demonstrating that the particle bound organic carbon is relatively homogeneous across a city. In addition, based on those carbon measurements, we have determined that the PM10-2.5 size range contains 30-40% carbon on average and plan to explore this portion in significant detail.
Health Data Collection. During the past year, we renewed the IRB approval for the project from Colorado State University in August 2010. We also obtained IRB approvals from Banner Health to obtain emergency department from North Colorado Medical Center (NCMC) in Greely, CO and from COMIRB to collect data from the University of Colorado Hospital and Denver Health Hospitals in Denver, CO. We are continuing to work with Medical Center of Aurora, Rose Medical Center, Swedish Medical Center, St. Anthony Medical Center, and Porter Adventist (Denver emergency departments) to get approval to participate in this study.
We have obtained emergency department data for the period January 1, 2009 – June 2010 from NCMC. The data acquisition took several rounds of collection to arrive at the correct data. The first several rounds were incomplete (i.e., did not include all emergency department visits for this time period). The completeness of the data was examined using the methods described in the quality assurance plan for the project; through this process it was discovered that visits for specific types of diagnoses were not included in the dataset. We now have the complete dataset for this time period. We have just received emergency department data from University of Colorado Hospital and Denver Health for the time period January 1, 2009 – December 31, 2010.
In the coming year, 2011, we will continue our efforts with the continuous mass concentration measurement network and data analysis, health data collection, and operation of the filter sampling network as well as completing most of the chemical analysis of the collected filters.