Modeling indoor particulate exposures in inner-city school classrooms.
Outdoor air pollution penetrates buildings and contributes to total indoor exposures. We investigated the relationship of indoor to outdoor particulate matter in inner-city school classrooms. The School Inner City Asthma Study investigates the effect of classroom-based environmental exposures on students with asthma in the northeast United States. Mixed effects linear models were used to determine the relationships between indoor PM2.5(particulate matter) and black carbon (BC), and their corresponding outdoor concentrations, and to develop a model for predicting exposures to these pollutants. The indoor-outdoor sulfur ratio was used as an infiltration factor of outdoor fine particles. Weeklong concentrations of PM2.5and BC in 199 samples from 136 classrooms (30 school buildings) were compared with those measured at a central monitoring site averaged over the same timeframe. Mixed effects regression models found significant random intercept and slope effects, which indicate that: (1) there are important PM2.5sources in classrooms; (2) the penetration of outdoor PM2.5particles varies by school and (3) the site-specific outside PM2.5levels (inferred by the models) differ from those observed at the central monitor site. Similar results were found for BC except for lack of indoor sources. The fitted predictions from the sulfur-adjusted models were moderately predictive of observed indoor pollutant levels (out of sample correlations: PM2.5: r2=0.68, BC; r2=0.61). Our results suggest that PM2.5has important classroom sources, which vary by school. Furthermore, using these mixed effects models, classroom exposures can be accurately predicted for dates when central site measures are available but indoor measures are not available.
Boston Children's Hospital, Boston, Massachusetts, USA.|Harvard Medical School, Boston, Massachusetts, USA.
Jonathan M
JM
Gaffin
Boston Children's Hospital, Boston, Massachusetts, USA.
Carter R
CR
Petty
Boston Children's Hospital, Boston, Massachusetts, USA.|Harvard Medical School, Boston, Massachusetts, USA.|Region 1 New England Pediatric Environmental Health Specialty Unit, Boston, Massachusetts, USA.
Marissa
M
Hauptman
T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.
Choong-Min
CM
Kang
T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.
Jack M
JM
Wolfson
T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.
Yara
Y
Abu Awad
T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.
Qian
Q
Di
Harvard Medical School, Boston, Massachusetts, USA.|T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.|Massachusetts General Hospital, Boston, Massachusetts, USA.
Peggy S
PS
Lai
Boston Children's Hospital, Boston, Massachusetts, USA.|Harvard Medical School, Boston, Massachusetts, USA.
William J
WJ
Sheehan
Boston Children's Hospital, Boston, Massachusetts, USA.|Harvard Medical School, Boston, Massachusetts, USA.
Sachin
S
Baxi
T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.
Brent A
BA
Coull
T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.
Joel D
JD
Schwartz
Harvard Medical School, Boston, Massachusetts, USA.|T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.|Channing Laboratory, Brigham and Women's Hospital, Boston, Massachusetts, USA.
Diane R
DR
Gold
T.H. Chan Harvard School of Public Health, Boston, Massachusetts, USA.
Petros
P
Koutrakis
Boston Children's Hospital, Boston, Massachusetts, USA.|Harvard Medical School, Boston, Massachusetts, USA.
Wanda
W
Phipatanakul
D016902:Air Pollution, Indoor; D004781:Environmental Exposure; D008962:Models, Theoretical; D052638:Particulate Matter / Q000032:analysis*; D012574:Schools; D014505:Urban Population
D052638:Particulate Matter