The pro-inflammatory role of air pollutants and their modifying influence on allergic inflammation may partly explain the increase in asthma prevalence, morbidity, and mortality. Agents that have major acute effects must be considered along with an understanding of the relevant personal exposures of susceptible individuals. However, it is unclear from the epidemiological research the extent to which associations between asthma outcomes and regulated EPA criteria air pollutants such as nitrogen dioxide (NO2)are independent or attributable to other monitored criteria pollutants such as particulate matter (PM) mass, or to air toxics not usually monitored such as combustion-related organic compounds. We propose to conduct an asthma panel study with daily repeated measurements of morbidity and pollutant exposures in 64 pediatric asthmatics living in areas with high air pollution levels: an area of East Los Angeles (vehicular emission source site) and Riverside (down-wind smog receptor site). Morbidity will be measured as acute asthma symptom severity, lung function, and as-needed asthma medication use.
Specific Aims i nclude examining the relationships of daily asthma morbidity to: (1) personal exposures to airborne PM measured in real-time; (2) personal exposures to 24-hr average concentrations of PM10 elemental and organic compounds (EC-OC); (3) personal exposures to 24-hr average NO2 collected concurrently with the above exposures; and (4) NO2 and PM exposures in single as compared with co-pollutant models using the metrics in aims one-three. Strengths of independent and interactive pollutant effects will be examined to test the hypothesis that personal PM exposures, including EC-OC, modifies the respiratory health effects of personal NO2 exposures, but confounds outdoor NO2, an indicator gas for traffic-related pollutants. Personal exposure models will be developed using a nested sample of personal exposures to predict PM and NO2 exposures for the two study regions. Two panels of 32 asthmatics will be followed for two months, one at each site (total 3,584 person-days). Dosimetric models will be developed using personal and exposure-adjusted PM and NO2 above to assess whether dose estimates enhance associations. Long-term goals are to improve knowledge about the independent and combined adverse effects of particulate and gaseous air pollutants by examining acute exposures and responses using ambulatory monitoring methods.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES011615-04
Application #
6889183
Study Section
Special Emphasis Panel (ZRG1-EDC-3 (01))
Program Officer
Tinkle, Sally S
Project Start
2002-07-15
Project End
2007-04-03
Budget Start
2005-05-01
Budget End
2006-04-30
Support Year
4
Fiscal Year
2005
Total Cost
$420,599
Indirect Cost
Name
University of California Irvine
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
046705849
City
Irvine
State
CA
Country
United States
Zip Code
92697
Delfino, Ralph J; Staimer, Norbert; Tjoa, Thomas et al. (2015) Relations of exhaled nitric oxide and FEV1 to personal endotoxin exposure in schoolchildren with asthma. Occup Environ Med 72:830-6
Delfino, Ralph J; Staimer, Norbert; Tjoa, Thomas et al. (2013) Airway inflammation and oxidative potential of air pollutant particles in a pediatric asthma panel. J Expo Sci Environ Epidemiol 23:466-73
Ducret-Stich, Regina E; Delfino, Ralph J; Tjoa, Thomas et al. (2012) Examining the representativeness of home outdoor PM(2.5), EC, and OC estimates for daily personal exposures in Southern California. Air Qual Atmos Health 5:335-351
Delfino, Ralph J; Staimer, Norbert; Tjoa, Thomas (2011) Personal endotoxin exposure in a panel study of school children with asthma. Environ Health 10:69
Floro, Josh N; Dunton, Genevieve E; Delfino, Ralph J (2009) Assessing physical activity in children with asthma: convergent validity between accelerometer and electronic diary data. Res Q Exerc Sport 80:153-63
Delfino, Ralph J; Chang, Joyce; Wu, Jun et al. (2009) Repeated hospital encounters for asthma in children and exposure to traffic-related air pollution near the home. Ann Allergy Asthma Immunol 102:138-44
Delfino, R J; Brummel, S; Wu, J et al. (2009) The relationship of respiratory and cardiovascular hospital admissions to the southern California wildfires of 2003. Occup Environ Med 66:189-97
Chang, J; Delfino, R J; Gillen, D et al. (2009) Repeated respiratory hospital encounters among children with asthma and residential proximity to traffic. Occup Environ Med 66:90-8
Delfino, Ralph J; Staimer, Norbert; Tjoa, Thomas et al. (2008) Personal and ambient air pollution exposures and lung function decrements in children with asthma. Environ Health Perspect 116:550-8
Delfino, R J (2006) Think globally, breathe locally. Thorax 61:184-5

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