Grantee Research Project Results

Health Effects of Concentrated Ambient Particles from the Central Valley of California

EPA Grant Number: R827995
Title: Health Effects of Concentrated Ambient Particles from the Central Valley of California
Investigators: Pinkerton, Kent E. , Sioutas, Constantinos
Current Investigators: Pinkerton, Kent E. , Smith, Kevin R. , Sioutas, Constantinos
Institution: University of California - Davis , University of Southern California
EPA Project Officer: Chung, Serena
Project Period: February 1, 2000 through January 31, 2003 (Extended to July 31, 2003)
Project Amount: $633,328
RFA: Airborne Particulate Matter Health Effects (1999) RFA Text |  Recipients Lists
Research Category: Particulate Matter , Air , Human Health

Description:

The goal of this proposal is to examine the mechanisms of particulate toxicity in the lungs of rats following short-term (3 day) exposure to concentrated ambient particles of the Fresno area during the Fall and Winter months when particle size and composition in this region of California are dramatically different. We wish to examine the effects these particles exert on epithelial cells of the airways, centriacinar regions, and alveoli. Since epithelial cells are the first cells in the respiratory tract to come into contact with inhaled particles, we hypothesize that damage to these cells can serve as a direct and highly sensitive measure of particle toxicity. We hypothesize that epithelial-particle interactions initiate a cascade of events that underlie adverse effects associated with inhaled particles. We hypothesize that particle toxicity begins with DNA damage in epithelial cells, thus accentuating cytotoxic events, leading to cell death. In turn, cell death begins the process of cellular proliferation. Each of these events impact negatively on the ability of the lungs to translocate and clear particles, thus leading to further irritation and injury. We will test each of these hypotheses using novel approaches to examine epithelial cell structure and function throughout the airways and alveoli.

Approach:

A series of acute inhalation exposures to laboratory animals (i.e. rats) will be conductred. Small-scale, portable Ultrafine, Fine and Coarse Particle Concentrators, suitable for animal inhalation exposures, will be deployed to the CSU Fresno campus. In the first year of the study, exposures will be made to concentrated fine and ultrafine particles (0-2.5 mm) during the Winter months. The concentrations of these particles (especially their carbonaceous component) are expected to be higher during this season compared to other seasons of the year. During the Fall months, exposures will be conducted to coarse particles, as they comprise the majority of the ambient PM during this season of the year. During the Winter of the second year, exposure will be conducted to concentrated fine particles without their sulfate and nitrate component. The 0-0.3 mm Concentrator will be used for this exposure series. During the Winter of the third year, exposures will be conducted to ultrafine PM only. During the Fall of each year, coarse PM exposures will be conducted. Such exposure scenarios will allow us to explore both particle size and to a limited degree particle composition to better understand health effects associated with exposure to concentrated ambient particles in the Fresno area. State-of-the-art techniques to measure epithelial cytoxicity, proliferation, and DNA damage will be used. The sensitivity of epithelial cells to particulate matter will be determined by airway location and generation within the tracheobronchial tree of the rat. These studies will utilize a new generation of recently developed portable Particle Concentrators to maintain concentrated particles in an airborne state and supply them to exposure chambers for laboratory animal inhalation studies.

Expected Results:

Improved understanding of concentrated ambient PM effects on the respiratory tract within anatomically distinct regions from the trachea to the alveolus for better extrapolation of findings to humans. Better understanding of acute (3 day) effects of PM episodes. Evaluation of causal relationships between specific PM components and biological responses. Comparison of outcomes of real-life ambient PM studies in Fresno to those of ongoing health studies at UC Davis using artificial preparations of carbonaceous and ammonium nitrate aerosols. Improvement in Risk Assessment: Evaluate biological responses to actual atmospheric mixtures relevant to the rural/urban environment of Fresno, CA correlated to extensive ongoing air monitoring data collected during the same temporal timeframe.

Publications and Presentations:

Publications have been submitted on this project: View all 9 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 7 journal articles for this project

Supplemental Keywords:

PM2.5, PM10, particle size and composition., RFA, Health, Scientific Discipline, Air, Geographic Area, particulate matter, Toxicology, air toxics, Environmental Chemistry, Health Risk Assessment, State, Risk Assessments, Molecular Biology/Genetics, ambient air quality, particle size, airway epithelial cells, PM 2.5, DNA damage, cytotoxic events, chemical mixtures, lung inflammation, particulate exposure, Acute health effects, inhaled, PM, California (CA), respiratory, ultrafine particles, animal inhalation study

Progress and Final Reports:

2000 Progress Report

2001 Progress Report

2002

Final Report