Long-Term Morbidity and Mortality Related to Exposures to Particulate Matter and Associated Air PollutantsEPA Grant Number: R826777
Title: Long-Term Morbidity and Mortality Related to Exposures to Particulate Matter and Associated Air Pollutants
Investigators: Lebowitz, Michael , O'Rourke, Mary Kay
Current Investigators: Lebowitz, Michael , Hill, A. , O'Rourke, Mary Kay , Pettygrove, S.
Institution: University of Arizona
EPA Project Officer: Chung, Serena
Project Period: October 1, 1998 through September 30, 2001 (Extended to September 30, 2002)
Project Amount: $363,426
RFA: Health Effects of Particulate Matter and Associated Air Pollutants (1998) RFA Text | Recipients Lists
Research Category: Air , Health Effects , Particulate Matter
There is a wealth of information indicating that particulate matter (PM) produces chronic pulmonary disease, but knowledge of the effects of PM on chronic cardiovascular disease is not sufficient currently. Further, the nature of the relationships between PM and chronic cardio-pulmonary diseases needs further exploration, including potential mechanisms, potential host susceptibility characteristics, and the differential effects of different size and species of PM. More recently, the impact of PM on cardio-pulmonary mortality has become a very important issue, with many issues of biological plausibility remaining unresolved. This project will examine the nature of the relationships utilizing unique longitudinal cardio- pulmonary & related host susceptibility data linked to unique exposure assessment data.
The primary objective of this project is to determine the chronic cardio-pulmonary morbidity and mortality in normal and susceptible individuals associated with indoor and ambient exposures to particulate matter (primarily PM10). Cardio-pulmonary responses to PM will be examined independently and in interactions with associated indoor and outdoor air pollutants (APs), and related environmental factors. Various host characteristics of potential susceptibility will be incorporated in the analyses. The secondary objective is to determine if particle size and the trace (elemental) metal content (& possible source) of the PM influence the relationships between PM exposures and cardio-pulmonary responses. Spatial-temporal sources of exposure variability as well as sources of errors will be examined and incorporated.
Measures of cardio-pulmonary morbidity and mortality in two Tucson longitudinal population cohorts of over 3000 subjects each (followed for 11 & 26 years) will be related to their PM (& other APs) exposures. A number of available indicators of susceptibility measured in these subjects will be utilized to see if they help predict those having long-term effects from PM exposures. The PM and AP exposures have been more than sufficient to affect these populations acutely, and the measures of susceptibility were important in estimating the health responses. The exposure assessments will utilize prior indoor/outdoor monitoring & exposure assessment (EA) modeling, taking into account various other exposure factors. Historical (residential and occupational) data and environmental data collected in these cohort studies will provide the data for EA modeling in which a parallel EA survey (NHEXAS) will also be used to obtain the estimates of total air exposures to PM, metals, and other relevant APs. Differential effects of the size and elemental composition of the PM exposures will be evaluated. Spatial & temporal variability estimates, and estimates of EA errors, will be evaluated also in regard to their influences on exposure-responses. Various longitudinal multivariate statistical analyses will be utilized also.
It is expected that clear exposure-response relationships between PM and the development of pulmonary morbidity (disease, symptoms, exacerbations) will be seen, especially in those considered more susceptible; there is a good likelihood that total PM exposures are related to cardiovascular (CV) morbidity. The size and elemental composition of the PM, and interactions with other AP exposures are likely to influence the relationships, with smaller PM & higher metal concentrations having greater effects. Children, especially those susceptible, will likely have more incident morbidity over time than others. (They also show more acute effects.) It is expected that there will be some contribution that PM (especially the more potent trace metal PM) to the risk of cardio-pulmonary mortality in the elderly who are at greater risk (especially risk related to "susceptibility"). Spatial-temporal variability will have some impact on the nature of the exposure-response relationship and their uncertainties. Because of the poor relationship of concentrations from single stationary PM monitors to actual exposures and the related health responses, the exact nature of the exposure-response relationships can still be considered hypothetical. Other exposure estimation errors will likely be very critical in the exposure- response relationships as well.
Improvements in Risk Assessment or Risk Management: Risk Assessment & Management: It is hypothesized that the findings will improve both significantly, due to the improvements in exposure-response relationships examined by this project, especially for the numerous susceptible sub-groups (children, elderly, those with preexisting disease, those at higher risk). Risk Assessments will also be improved with better characterization of the total PM exposure assessment estimates, the specification of size and certain composition elements, and the contributions of various other