2002 Progress Report: Urban PM2.5 Surface Chemistry and Interactions with Bronchoalveolar Lavage Fluid (BALF)EPA Grant Number: R827351C011
Subproject: this is subproject number 011 , established and managed by the Center Director under grant R827351
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: EPA NYU PM Center: Health Risks of PM Components
Center Director: N/A
Title: Urban PM2.5 Surface Chemistry and Interactions with Bronchoalveolar Lavage Fluid (BALF)
Investigators: Kendall, Michaela
Institution: New York University School of Medicine
EPA Project Officer: Chung, Serena
Project Period: June 1, 1999 through May 31, 2005 (Extended to May 31, 2006)
Project Period Covered by this Report: June 1, 2001 through May 31, 2002
RFA: Airborne Particulate Matter (PM) Centers (1999) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Particulate Matter , Air
The objective of this research project was to investigate the surface chemistry of urban fine particulate matter (PM2.5), and to quantify the adsorbed and desorbed species exposed to bronchoalveolar lavage fluid (BALF).
Progress in Year 1 of the Project. Urban background and roadside PM2.5 samples of different mass concentration and total weight were collected in triplicate in the South Bronx region of New York City (NYC). Simultaneously, the concentrations of other atmospheric pollutants (carbon monoxide [CO], nitrogen oxides [NOx], sulfur dioxide [SO2], ozone [O3], elemental carbon [EC]) were measured, and weather conditions recorded. The collected PM2.5 samples underwent one of the following three treatments: no treatment, treatment in vitro with BALF, or treatment in a saline solution (control). The surfaces of untreated, saline, and BALF-treated PM2.5 samples were then analysed using x-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). These results were compared with ambient air pollutant concentrations, weather variables, selected BALF characteristics, and results from a previous London study using identical methods.
Both surface techniques were useful in detecting surface species and observing changes in surface concentrations. The surface of untreated urban PM2.5 consisted of 79-87 percent carbon and 10-16 percent oxygen with smaller contributions of N, S, Si, and P in the samples from both locations. A wide variety of other inorganic materials (metals, Cl¯, NH4+) and organic species (aliphatic and aromatic hydrocarbons) were detected with TOF-SIMS. The surface characteristics of particles from the roadside and background sites were very similar, except for higher (p<0.05) nitrate concentrations at the roadside PM2.5 attributable to higher roadside NOx concentrations. Comparable species and quantities were identified in a previous study of London PM2.5, but PM2.5 surface chemistry differed considerably from other sources, particularly in surface concentrations of oxygen and trace species.
After treatment with BALF, the N-C signal detected by XPS analysis increased by an average of 372±203 percent, indicating significant surface adsorption of protein or other N-containing biomolecules. Lower N-C signals were observed for BALF from smokers. TOF-SIMS data confirmed N adsorption after BALF treatment, and also indicated an adsorption of phospholipid on the PM2.5 surfaces in terms of increased fragment ions characteristic of phospholipid adsorption. The primary phospholipid in BALF is dipalmitoyl phosphatidylcholine (DPPC), although positive identification was not possible. Oxygen content of PM2.5 surfaces was the most significant determinant of both N-C and phospholipid adsorption. The XPS signal of the soluble species NH4+, NO22-, Si, and S decreased in both saline and BALF treated samples, suggesting that these species may be bioavailable in the lung.
Thus, we have shown that PM2.5 surface chemistry can be analyzed and differentiated using two sensitive surface analytical techniques, XPS and TOF-SIMS. PM2.5 surfaces in NYC are similar in overall composition to PM2.5 surfaces analyzed in London. Distinct differences in surface chemistry also were found comparing urban PM2.5 from different types of locations. In particular, surface oxygen concentrations increased with "aged" PM2.5, so that clean air PM2.5 was greater than NYC and London PM2.5, which was greater than tobacco smoke PM2.5. We propose that such a difference may be an important, and hitherto unconsidered, determinant in the health effects of PM2.5 exposure. The wide variations in carbon:oxygen ratios detected could be used to distinguish smoke, urban and "clean air" PM2.5. In this study, we also confirmed results from previous studies that PM2.5 surfaces interact strongly with BALF over very short periods, and that PM2.5 immersed in BALF are desorbed of particular components and coated with biomolecules. We showed that consistently large increases of the N-C signal from PM2.5 surfaces occur as a result of interactions with BALF, and we attribute these increases to protein adsorption.
Future research will focus on identifying the specific biomolecules adsorbed on PM and quantifying the adsorption rates of these species and the factors that influence the adsorption rates. Furthermore, the efficiency and quantity of coating particles by the lung lining liquid and its components in healthy persons, smokers, and patients with respiratory diseases should be examined and compared.
Journal Articles on this Report : 1 Displayed | Download in RIS Format
|Other subproject views:||All 2 publications||2 publications in selected types||All 2 journal articles|
|Other center views:||All 112 publications||101 publications in selected types||All 89 journal articles|
||Kendall M, Guntern J, Lockyer NP, Jones FH, Hutton BM, Lippmann M, Tetley TD. Urban PM2.5 surface chemistry and interactions with bronchoalveolar lavage fluid. Inhalation Toxicology 2004;16(Suppl 1):115-128.||
Supplemental Keywords:air pollution, air pollutants, particulate matter, PM, fine particles, PM2.5, PM surface chemistry, bronchoalveolar lining fluid, BALF, chronic obstructive pulmonary disease, COPD, carbon monoxide, CO, nitrogen oxides, NOx, sulfur dioxide, SO2, ozone, O3, elemental carbon, EC, metals, susceptible populations, lung disease, respiratory disease, pulmonary disease, respiratory effects, pulmonary effects, New York City, New York, NY, London, smokers, tobacco smoke, phospholipid adsorption, health effects, PM exposure., RFA, Health, Scientific Discipline, PHYSICAL ASPECTS, Air, ENVIRONMENTAL MANAGEMENT, particulate matter, Environmental Chemistry, Health Risk Assessment, Risk Assessments, Environmental Monitoring, Physical Processes, Atmospheric Sciences, Risk Assessment, ambient air quality, atmospheric particulate matter, particulates, atmospheric particles, chemical characteristics, toxicology, ambient air monitoring, acute lung injury, airborne particulate matter, environmental risks, exposure, epidemelogy, COPD, lung hypoxia, air pollution, aerosol composition, atmospheric aerosol particles, pulmonary hypertension, human exposure, bronchoalveolar lining fluid, PM, airway contractile properties, exposure assessment
Progress and Final Reports:Original Abstract
Main Center Abstract and Reports:R827351 EPA NYU PM Center: Health Risks of PM Components
Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R827351C001 Exposure Characterization Error
R827351C002 X-ray CT-based Assessment of Variations in Human Airway Geometry: Implications for Evaluation of Particle Deposition and Dose to Different Populations
R827351C003 Asthma Susceptibility to PM2.5
R827351C004 Health Effects of Ambient Air PM in Controlled Human Exposures
R827351C005 Physicochemical Parameters of Combustion Generated Atmospheres as Determinants of PM Toxicity
R827351C006 Effects of Particle-Associated Irritants on the Cardiovascular System
R827351C007 Role of PM-Associated Transition Metals in Exacerbating Infectious Pneumoniae in Exposed Rats
R827351C008 Immunomodulation by PM: Role of Metal Composition and Pulmonary Phagocyte Iron Status
R827351C009 Health Risks of Particulate Matter Components: Center Service Core
R827351C010 Lung Hypoxia as Potential Mechanisms for PM-Induced Health Effects
R827351C011 Urban PM2.5 Surface Chemistry and Interactions with Bronchoalveolar Lavage Fluid (BALF)
R827351C012 Subchronic PM2.5 Exposure Study at the NYU PM Center
R827351C013 Long Term Health Effects of Concentrated Ambient PM2.5
R827351C014 PM Components and NYC Respiratory and Cardiovascular Morbidity
R827351C015 Development of a Real-Time Monitoring System for Acidity and Soluble Components in Airborne Particulate Matter
R827351C016 Automated Real-Time Ambient Fine PM Monitoring System