2003 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, 2002 through May 31, 2003
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 is 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).
This is one of the projects funded by the New York University (NYU) PM Center. The progress for the other projects is reported separately (see reports for R827351C001 through R827351C010, and R827351C012 through R827351C016).
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. Simultaneously, the concentrations of other atmospheric pollutants (CO, NOx, SO2, O3, elemental carbon) were measured and weather conditions recorded. The collected PM2.5 samples underwent one of 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 then were analyzed using x-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). These results then were compared with ambient air pollutant concentrations, weather variables, selected BALF characteristics, and results from a previous London study conducted 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 to 87 percent C and 10 to 16 percent O with smaller contributions of N, S, Si, and P in the samples from both locations. A wide variety of other inorganic (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 that were 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 O 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 dipalmitoylphosphatidylcholine (DPPC), although positive identification was not possible. O 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+, NO32-, Si, and S decreased in both saline and BALF-treated samples, showing 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 New York City are similar in overall composition to PM2.5 surfaces analyzed in London. Distinct differences in surface chemistry also were found when comparing urban PM2.5 from different types of locations. In particular, surface O concentrations increased with “aged” PM2.5, so that clean air PM2.5 was greater than New York City and London PM2.5, which was greater than tobacco smoke PM2.5. It is proposed that such a difference may be an important and hitherto unconsidered determinant in the health effects of PM2.5 exposure. The wide variations in C:O 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 is 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.
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 111 publications||100 publications in selected types||All 88 journal articles|
||Kendall M, Brown L, Trought K. Molecular adsorption at particle surfaces: a PM toxicity mediation mechanism. Inhalation Toxicology 2004;16(Suppl 1):99-105.||
Supplemental Keywords:thoracic particles, PM10, fine particles, PM2.5, ultrafine particles, PM 0.1, lung dosimetry models, human exposure models, pulmonary responses, cardiovascular responses, immunological responses, criteria air pollutants, concentrated ambient aerosols, aerosol, air pollutants, air pollution, airborne pollutants, airway disease, airway inflammation, airway variability, allergen, ambient air, ambient air quality, analytical chemistry, assessment of exposure, asthma, asthma morbidity, atmospheric monitoring, biological markers, childhood respiratory disease, children, combustion, combustion contaminants, combustion emissions, compliance monitoring, dosimetry, epidemiology, exposure, exposure and effects, health effects, heart rate variability, human exposure, human health, human health effects, incineration, lead, lung, mercury, morbidity, particulates, pulmonary, pulmonary disease, respiratory,, RFA, Health, PHYSICAL ASPECTS, Scientific Discipline, Air, ENVIRONMENTAL MANAGEMENT, particulate matter, Environmental Chemistry, Health Risk Assessment, Risk Assessments, Physical Processes, Environmental Monitoring, 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