The Effect of Changes in Diesel Exhaust Composition and After-Treatment Technology On Lung Inflammation and Resistance to Viral Infection

Transcription

1 The Effect of Changes in Diesel Exhaust Composition and After-Treatment Technology On Lung Inflammation and Resistance to Viral Infection Jake McDonald, Kevin Harrod, JeanClare Seagrave, Steve Seilkop and Joe Mauderly Lovelace Respiratory Research Institute, Albuquerque, NM Environmental Science and Health Impacts Program DOE Office of FreedomCar and Vehicle Technology James Eberhardt, Manager

2 Goals Determine the physical and/or chemical characteristics that drive health effects Need to see effects of different magnitude Need a range of exposure conditions with overlapping, yet different composition

3 Health Effects Non-cancer health effects of emerging interest Decreased resistance to infection after exposure to air pollutants has been implicated in several studies. Recently our lab has shown decreased clearance of Respiratory Syncitial Virus (RSV) and increased pathogenesis (more sick) after diesel exhaust exposures at our lowest exposure levels (Harrod et al.,2003)* Diesel exhaust, under some conditions, has also been shown to produce lung inflammation and oxidative stress in healthy rodents. * Am J. Resp. Cell and Mol. Biology, 28,

4 Study Design 1. Partial Load 2. High Load 3. Emiss. Red. 200 µg/m 3 PM (1&2) or equiv. dilution (3) 6 h/d 7 d exposure C57Bl/6 Mice Group 1 Group 2 Viral Clearance Lung pathogenesis Lung inflammation Sacrifice immediately after Last exposure day Instillation of RSV Lung inflammatory/oxidative stress indicators Sacrifice at 4 days

5 Engine/Fuel/Lube Oil Yanmar 5500 Watt Genset (YDG5500) 490 cc single cylinder engine Load induced by 500 watt lights (6 for partial and 11 for high) Lube oil: 15w/40 Rotella T (Shell) purchased off the shelf Oil changed prior to each exposure Fuel: Exposures 1 and 2: #2 Certification Fuel. #3: BP-15 ultra low S fuel

6 Fuel Properties API Gravity #2 Certification Fuel 35.8 BP-15 Fuel 37.5 Spec. gravity Viscosity Sulfur (ppm) Aromatics (vol %) Cetane index Cetane number

7 Catalyzed Ceramic Filter PERMIT TM Filters by CleanAIR Systems Technology verified by California Air Resources Board as Level 3 device (>85% PM reduction) >95% CO & THC reduction

8 Exposure System McDonald et al Aerosol Sci Technol., In Press

9 Exposure Atmosphere Characterization Particle Mass Particle Size Distribution (number and mass) NOx (NO + NO 2 ) NMVOC/speciated NMVOC SVOC/PM Organics Metals and associated elements Organic/Black carbon and inorganic ions

10 Particle Composition 300 µg/m Ammonium Sulfate Nitrate Organic Carbon Black Carbon 0 High Load Partial Load Emiss. Red. Control µg/m High Load Partial Load Emiss. Red. Control Ammonium Sulfate Nitrate

11 Particle Size

12 CO and Volatile Organics NMVOC µg/m3 CO ppm* Partial Load High Load Emiss. Red. Tech Filtered Air

13 Select Semi-Volatile and Heavy Organics ng/m 3 2.E+05 2.E+05 1.E+05 1.E+05 1.E+05 8.E+04 6.E+04 4.E+04 2.E+04 0.E+00 Partial Load High Load Emiss. Red Control SUM Alkanes (C15-C30) Sum other SVOC PAH Sum Phenanthrenes Sum Heavy PAH SUM oxy-pah SUM Naphthalenes 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Partial Load High Load Emiss. Red Control SUM Alkanes (C15-C30) Sum other SVOC PAH Sum Phenanthrenes Sum Heavy PAH SUM oxy-pah SUM Naphthalenes

14 Viral Persistance and Lung Inflammation by Histopathology absorbance units Viral Persistance ** Score ( 4 max) Histopathology (Inflammation/Injury) ** 0 FA Em. Red. FA P. Load FA H. Load 0 FA Em. Red. FA P.Load FA H. Load

15 Oxidative Lung Damage Heme-Oxygenase (Oxidative Stress Marker) * ** absorbance FA EM.Red. FA P.Load FA H.Load

16 Lung Inflammatory Indicators pg/(0.1mg protein) TNF-alpha FA Em.Red. FA P.Load FA H.Load **

17 Summary Engine load variation and catalyzed trap/low S fuel were used to produce exposure atmospheres of different composition Observed Differences in organic content/composition and particle size Differences in health response

18 What s Next? Complete chemical and biological analyses Investigate additional exposure atmosphere compositions High load plus organic/inorganic denuders (strippers) Ceramic trap with no catalyst Transients to increase oil content Spark Ignition Relate compositional differences to health effects quantitatively to improve understanding of health drivers

19 Further Acknowledgments Desert Research Institute Organic Analytical Lab-VOC Environmental Analysis Facility- Carbon/Ions BP: Global Fuels Technology Group Donation of BP-15 fuel