2009 Progress Report: Health Effects and Characterization of Urban and Rural Coarse ParticulateMatter in Northeastern Colorado

EPA 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. , 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, 2009 through December 31,2009
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.  

Progress Summary:

During the second year, we were focused on finalizing the uncertainty and quality assurance evaluation of the continuous PM10-2.5 & PM2.5 monitoring equipment (TEOM 1405-DF), maintaining the network of four continuous PM10-2.5 & PM2.5 mass concentration monitors (two in Denver and two in Greeley), creating a data processing system for that measurement network, exploring the spatiotemporal variability of the PM10-2.5 and PM2.5 mass concentrations using the first year of data, building PM10-2.5/PM2.5 filter samplers, evaluating the uncertainty of those filter samplers, and obtaining medical data from the hospitals in Denver and Greeley.  In addition, we have continually updated our QAPP as we have further developed measurement and data analysis protocols.  Finally, and maybe most significantly, we decided on an acronym for this project: Coarse Rural Urban Sources and Health (CRUSH) study.
Continuous Mass Concentration Results. As of the close of 2009, we have collected approximately 1 year of continuous PM2.5 and PM10-2.5 mass concentrations at two sites in Denver and two sites in Greeley.  After processing these measurements through our own data system (see full report), we explored the spatial correlations and temporal trends to inform our knowledge of the origins and variability of the PM10-2.5 and PM2.5.  In the summary, we will highlight just the one most interesting result, but more results and discussion can be found in the full report.
             Our initial hypothesis (based on aerosol dynamics theory) is that PM10-2.5 is more spatially heterogeneous than PM2.5.  An initial way to explore these relationships is to scatter plot one site hourly average mass concentration versus another.  For example, Figure 1 below shows the hourly PM2.5 for the two sites in Denver in the left panel and the hourly PM2.5 for the two sites in Greeley in the right panel.  Figure 2 shows the same information but for PM10-2.5 instead of PM2.5.  The first thing you notice is that PM10-2.5 in Greeley is fairly spatially homogeneous, in fact, more homogeneous than the PM2.5

Figure 1

In Denver, there appears to be a stronger relationship between sites for PM10-2.5 than for PM2.5, but there is obviously something else going on with PM10-2.5 at Alsup Elementary as there are several extremely high mass concentrations.  We are hesitant to draw quantitative conclusions at this point in part because
Figure 2
there is substantially more uncertainty associated with the PM2.5 channel of the TEOM. Still, at present we are becoming convinced that our initial hypothesis, at least for these few sites pairs in Colorado, might be rejected.
Characterization via Filter Sample Collection.  To characterize PM10-2.5 and PM2.5, we need to be able to collect and bring the PM samples back to the lab for subsequent chemical and biological analysis. To keep consistency with the continuous mass concentration characterization efforts, we wanted to employ the same type of size separation devices. The TEOM 1405-DF uses a PM­10 impactor to remove all particles larger than 10 µm in diameter, and then uses a virtual impactor to split the PM2.5 from the PM10-2.5.  The TEOM operates at a flow rate of 16.67 lpm and collects enough mass over 6 minutes to measure more than just noise. That flow rate is the standard flow rate for PM collection equipment and many particle separation devices have been developed specifically for the flow rate.  However, when detailed speciation is desired, higher flow rates and more mass collection is critical.  As such, we needed to scale the TEOM PM10 impactor and PM10-2.5/PM2.5 virtual impactor up in size to keep the same size cut with a higher flow rate.  Luckily, efforts by both Costas Sioutas and Paul Solomon have already addressed this design issue.  We were able to use published modifications to the classic 16.67 lpm PM10 impactor and a virtual impactor loan from the Sioutas group to design and build the particle separation inlet for the new filter samplers.  We created four filter samplers to allow us to explore spatial variability of the chemical species within both Denver and Greeley.  Before deploying these samplers, we ran them co-located to determine their inherent uncertainty.  More details of this can be found in the full report.

Future Activities:

In the coming year, 2010, we will continue our efforts with the continuous mass concentration measurement network and data analysis, health data collection, deployment and operation of the filter sampling network as well as initiating the chemical analysis of the collected filters. 

Journal Articles:

No journal articles submitted with this report: View all 14 publications for this project

Supplemental Keywords:

exposure, human health, dose-response, metals, epidemiology, modeling
, RFA, Scientific Discipline, Air, Geographic Area, particulate matter, Health Risk Assessment, State, Biology, atmospheric particulate matter, PM10, atmospheric particles, cardiopulmonary responses, human health effects, bioavailability, cardiovascular vulnerability, cardiotoxicity, coarse pm, exposure assessment, chemical speciation sampling

Progress and Final Reports:

Original Abstract
  • 2008 Progress Report
  • 2010 Progress Report
  • 2011 Progress Report
  • 2012 Progress Report
  • Final Report