estimating air pollution infiltration efficiencies for
TRANSCRIPT
![Page 1: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/1.jpg)
![Page 2: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/2.jpg)
Estimating Air Pollution Infiltration Efficiencies for Exposure
Assessment and Epidemiology
Ryan Allen, PhD Faculty of Health Sciences
Simon Fraser University Burnaby, BC
![Page 3: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/3.jpg)
Overview• Why estimate residential infiltration efficiencies?• How?
–Tracer–Recursive model
• Description, validation, examples
• Application to epi–Panel studies–Model building for other study designs
• Windsor results–And possible future directions
![Page 4: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/4.jpg)
AmbientPM2.5
“Leaky”
AmbientPM2.5
Infiltration Efficiency (Finf )
AmbientPM2.5
“Tightly Sealed”
–Total exposure = ambient + nonambient
• The fraction of the ambient concentration that penetrates indoors and remains suspended
• Function of AER, penetration, deposition
• Exposure to ambient pollution depends on Finf & time spent outdoors
![Page 5: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/5.jpg)
Why?• To better interpret epi. results from different
locations and/or from different seasons
• Reduce exposure misclassification in epi studies
• To tease apart health impacts of ambient vs. nonambient pollution
![Page 6: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/6.jpg)
• To better interpret epi. results from different locations and/or from different seasons
• Reduce exposure misclassification in epi studies
• To tease apart health impacts of ambient vs. nonambient pollution
Hystad et al., JESEE, in press
Why?
![Page 7: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/7.jpg)
72%
8%
18%2%
Vegetative BurningMobile
SecondaryCrustal
58%
4%
14%
24%
Why?• To better interpret epi. results from different locations and/or from different
seasons
• Reduce exposure misclassification in epi studies
• To tease apart health impacts of ambient vs. nonambient pollution
Larson et al., JAWMA, 2004
Outdoors (12.2 ug/m3) Indoors (9.4 ug/m3)
![Page 8: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/8.jpg)
How?• Tracer (most commonly sulfur or sulfate)
–Requires that there be no (or few) indoor or personal sources
–Indoor/outdoor ratio or slope gives Finf
• Recursive model–Requires continuous indoor/outdoor
measurements (e.g. nephelometer, DustTrak)–Does not require absence of indoor sources–Shows promise for estimating Finf of pollutants
without good tracers (e.g. ultrafines)
![Page 9: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/9.jpg)
Average indoor concentration during the hour
=
Some fraction of the average outdoor concentrationduring the hour
+
Some fraction of the indoor concentrationthat remains from the PREVIOUS hour
+Contribution from indoor sources during the hour
int
int
outt
int SCCC 121 ++= −ββ
~0
2
1inf 1 β
β−
=+
=ka
PaF
Recursive Model Technique
Allen et al., ES&T, 2003
![Page 10: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/10.jpg)
0
1
2
3
4
5
6
7
8
22-Feb 24-Feb 26-Feb 28-Feb 1-Mar 3-Mar
Ligh
t Sca
tterin
g C
oeffi
cien
t (x1
0 -5 m-1
)
OutdoorsIndoorsIndoor Source Hour
Recursive Model Technique
Allen et al., ES&T, 2003
![Page 11: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/11.jpg)
Recursive Model Technique Validation
Allen et al., ES&T, 2003
![Page 12: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/12.jpg)
Recursive Model Technique Validation
Allen et al., JESEE, 2007
![Page 13: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/13.jpg)
Recursive Model Technique Examples
Barn et al., JESEE, 2008
• Air cleaner effectiveness in woodsmoke and forest fire impacted community
![Page 14: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/14.jpg)
Recursive Model Technique Examples
Polidori et al., JAWMA, 2007
• Contributions of ambient and nonambient sources at retirement facilities in southern CA
![Page 15: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/15.jpg)
Application of Finf to Epidemiology Panel Studies
Allen et al., Inhal. Tox., 2008
![Page 16: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/16.jpg)
Application of Finf to Epidemiology Model Development for Large Studies
Koenig et al., EHP., 2005
R2 = 0.60
R2 = 0.66
![Page 17: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/17.jpg)
Application of Finf to Epidemiology Model Development for Large Studies
Hystad et al., JESEE., In Press
• Victoria, BC
• Spatial property assessment data (SPAD)
• Model including season predicts 54% of total variance
• Potentially allows Finf to be estimated in many homes without I/O monitoring
![Page 18: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/18.jpg)
Windsor PM2.5 Finf
Mean: 0.36IQR: 0.26 – 0.44
Mean: 0.33IQR: 0.25 – 0.40
52 homes monitored in both seasons
![Page 19: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/19.jpg)
Windsor PM2.5 Finf Models
Season Predictor(s) R2
Summer I-O Temp Diff, Window Opening 0.36
Winter Building age, air cleaner use 0.20
![Page 20: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/20.jpg)
Windsor UFP Finf
Mean: 0.34IQR: 0.19 – 0.50
Mean: 0.21IQR: 0.13 – 0.27
27 homes monitored in both seasons
![Page 21: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/21.jpg)
Windsor UFP Finf Models
Season Predictor(s) R2
Summer Outdoor Temp, Window Opening 0.56
Winter ----- -----
![Page 22: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/22.jpg)
PM2.5 Finf vs. UFP Finf
r = 0.44
r = 0.68
![Page 23: Estimating Air Pollution Infiltration Efficiencies for](https://reader033.vdocuments.mx/reader033/viewer/2022051618/6280cbf98a973a71a113e3a9/html5/thumbnails/23.jpg)
Other Possibilities for Windsor Data• Continue development of Finf models• Comparison of Finf for different PM species
–PM2.5–UFP–LAC
• Health effects–Ambient / nonambient PM vs. lung function