ACS ES&T Air,
Journal Year:
2024,
Volume and Issue:
1(8), P. 767 - 779
Published: May 21, 2024
Indoor
air
quality
is
critical
to
human
health,
as
individuals
spend
an
average
of
90%
their
time
indoors.
However,
indoor
particulate
matter
(PM)
sensor
networks
are
not
deployed
often
outdoor
networks.
In
this
study,
PM2.5
exposure
investigated
via
2
low-cost
in
Pittsburgh.
The
concentrations
reported
by
the
were
fed
into
a
Monte
Carlo
simulation
predict
daily
for
4
demographics
(indoor
workers,
schoolchildren,
and
retirees).
Additionally,
study
compares
effects
different
correction
factors
on
from
PurpleAir
sensors,
including
both
empirical
physics-based
corrections.
results
show
that
mean
varied
1.5
μg/m3
or
less
when
similar.
When
PM
lower
than
outdoor,
increasing
spent
outdoors
increased
up
3
μg/m3.
These
differences
highlight
importance
carefully
selecting
sites
deployment
value
having
robust
network
with
placement.
Environmental Science & Technology,
Journal Year:
2022,
Volume and Issue:
56(19), P. 13607 - 13621
Published: Sept. 22, 2022
Smoke
from
wildfires
is
a
growing
health
risk
across
the
US.
Understanding
spatial
and
temporal
patterns
of
such
exposure
its
population
impacts
requires
separating
smoke-driven
pollutants
non-smoke
long
time
series
to
quantify
measure
impacts.
We
develop
parsimonious
accurate
machine
learning
model
daily
wildfire-driven
PM2.5
concentrations
using
combination
ground,
satellite,
reanalysis
data
sources
that
are
easy
update.
apply
our
contiguous
US
2006
2020,
generating
estimates
smoke
over
10
km-by-10
km
grid
use
these
characterize
levels
trends
in
PM2.5.
contributions
have
increased
by
up
5
μg/m3
Western
last
decade,
reversing
decades
policy-driven
improvements
overall
air
quality,
with
fastest
for
higher
income
populations
predominantly
Hispanic
populations.
The
number
people
locations
at
least
1
day
above
100
per
year
has
27-fold
including
nearly
25
million
2020
alone.
Our
set
can
bolster
efforts
comprehensively
understand
drivers
societal
extremes
wildfire
smoke.
The Science of The Total Environment,
Journal Year:
2021,
Volume and Issue:
807, P. 150797 - 150797
Published: Oct. 7, 2021
Given
the
growing
interest
in
community
air
quality
monitoring
using
low-cost
sensors,
30
PurpleAir
II
sensors
(12
outdoor
and
18
indoor)
were
deployed
partnership
with
members
living
adjacent
to
a
major
interstate
freeway
from
December
2017-
June
2019.
Established
assurance/quality
control
techniques
for
data
processing
used
sensor
was
evaluated
by
calculating
completeness
summarizing
PM2.5
measurements.
To
evaluate
performance,
correlation
coefficients
(r)
of
divergence
(CoD)
assess
temporal
spatial
variability
between
sensors.
concentrations
also
compared
traffic
levels
sensors'
ability
detect
pollution.
indoor
indoor/outdoor
(I/O)
ratios
during
resident-reported
activities
calculated
compared,
linear
mixed-effects
regression
model
developed
quantify
impacts
ambient
quality,
microclimatic
factors,
human
on
PM2.5.
In
general,
performed
more
reliably
than
(completeness:
73%
versus
54%).
All
highly
temporally
correlated
(r
>
0.98)
spatially
homogeneous
(CoD<0.06).
The
observed
I/O
consistent
existing
literature,
explains
>85%
variation
levels,
indicating
that
detected
various
sources.
Overall,
this
study
finds
community-maintained
can
effectively
monitor
PM2.5,
main
concerns
resulting
incompleteness.
Environment International,
Journal Year:
2021,
Volume and Issue:
158, P. 106897 - 106897
Published: Sept. 30, 2021
High-resolution,
high-quality
exposure
modeling
is
critical
for
assessing
the
health
effects
of
ambient
PM2.5
in
epidemiological
studies.
Using
sparse
regulatory
measurements
as
principal
model
inputs
may
result
two
issues
prediction:
(1)
they
affect
models'
accuracy
predicting
spatial
distribution;
(2)
internal
validation
based
on
these
not
reliably
reflect
performance
at
locations
interest
(e.g.,
a
cohort's
residential
locations).
In
this
study,
we
used
from
publicly
available
commercial
low-cost
network,
PurpleAir,
with
an
external
dataset
representative
sample
participants
Adult
Changes
Thought
-
Air
Pollution
(ACT-AP)
to
improve
prediction
cohort
participant
locations.
We
also
proposed
metric
component
analysis
(PCA)
PCA
distance
assess
similarity
between
monitor
and
guide
deployment
data
selection.
The
was
spatiotemporal
framework
51
"gold-standard"
monitors
58
PurpleAir
development,
well
105
home
validation,
Puget
Sound
region
Washington
State
June
2017
March
2019.
After
including
calibrated
part
dependent
variable,
R2
root-mean-square
error,
RMSE,
two-week
concentration
averages
improved
0.84
2.22
μg/m3
0.92
1.63
μg/m3,
respectively.
RMSE
long-term
over
period
0.72
1.01
0.79
0.88
predictions
incorporating
demonstrated
sharper
urban-suburban
gradients.
shorter
distances
model's
more
substantially
than
longer
distances,
supporting
use
metric.
Environmental Research Health,
Journal Year:
2022,
Volume and Issue:
1(1), P. 015003 - 015003
Published: June 30, 2022
Previous
research
on
the
health
and
air
quality
impacts
of
wildfire
smoke
has
largely
focused
impact
outdoor
quality;
however,
many
people
spend
a
majority
their
time
indoors.
The
indoor
smoke-impacted
days
is
unknown.
In
this
analysis,
we
use
publicly
available
data
from
an
existing
large
network
low-cost
fine
particulate
matter
(PM2.5)
monitors
to
quantify
relationship
between
in
2020
across
western
United
States
(US).
We
also
investigate
possible
regional
socioeconomic
trends
for
regions
surrounding
six
major
cities
US.
find
PM2.5
concentrations
are
82%
or
4.2
µg
m−3
(median
all
US
year
2020;
interquartile
range,
IQR:
2.0–7.2
m−3)
higher
compared
smoke-free
days.
Indoor/outdoor
ratios
show
variability
by
region,
particularly
However,
ratio
indoor/outdoor
less
than
1
(i.e.
lower
outdoor)
at
nearly
indoor-outdoor
monitor
pairs
Although
typically
days,
that
heavily
(outdoor
>
55
m−3),
can
exceed
35
24
h
standard
set
Environmental
Protection
Agency.
Further,
total
daily-mean
increase
2.1
with
every
10
PM2.5.
statistically
significant
linear
regression
slopes
pairs;
1.0–4.3
These
results
environments
included
our
remaining
indoors
during
events
currently
effective,
but
limited,
strategy
reduce
exposure.
Sensors,
Journal Year:
2022,
Volume and Issue:
22(13), P. 4741 - 4741
Published: June 23, 2022
Large
quantities
of
real-time
particle
data
are
becoming
available
from
low-cost
monitors.
However,
it
is
crucial
to
determine
the
quality
these
measurements.
The
largest
network
monitors
in
United
States
maintained
by
PurpleAir
company,
which
offers
two
monitors:
PA-I
and
PA-II.
have
a
single
sensor
(PMS1003)
PA-II
employ
independent
PMS5003
sensors.
We
new
calibration
factor
for
monitor
revise
previously
published
algorithm
(ALT-CF3).
From
API
site,
we
downloaded
83
million
hourly
average
PM2.5
values
database
Washington,
Oregon,
California
between
1
January
2017
8
September
2021.
Daily
outdoor
means
194
were
compared
daily
47
nearby
Federal
regulatory
sites
using
gravimetric
Reference
Methods
(FRM).
find
revised
3.4
For
monitors,
determined
(also
3.4)
comparing
26
117
sites.
These
results
show
that
measurements
can
agree
well
with
when
an
optimum
found.
Proceedings of the National Academy of Sciences,
Journal Year:
2023,
Volume and Issue:
120(50)
Published: Dec. 4, 2023
Building
conditions,
outdoor
climate,
and
human
behavior
influence
residential
concentrations
of
fine
particulate
matter
(PM2.5).
To
study
PM2.5
spatiotemporal
variability
in
residences,
we
acquired
paired
indoor
measurements
at
3,977
residences
across
the
United
States
totaling
>10,000
monitor-years
time-resolved
data
(10-min
resolution)
from
PurpleAir
network.
Time-series
analysis
statistical
modeling
apportioned
to
sources
(median
contribution
=
52%
total,
coefficient
variation
69%),
episodic
emission
events
such
as
cooking
(28%,
CV
210%)
persistent
(20%,
112%).
Residences
temperate
marine
climate
zone
experienced
higher
infiltration
factors,
consistent
with
expectations
for
more
time
open
windows
milder
climates.
Likewise,
all
zones,
factors
were
highest
summer
lowest
winter,
decreasing
by
approximately
half
most
zones.
Large
outdoor-indoor
temperature
differences
associated
lower
suggesting
particle
losses
active
filtration
occurred
during
heating
cooling.
Absolute
contributions
both
increased
wildfire
events.
Infiltration
decreased
periods
high
PM2.5,
wildfires,
reducing
potential
exposures
outdoor-origin
particles
but
increasing
indoor-origin
particles.
Time-of-day
reveals
that
are
frequent
mealtimes
well
on
holidays
(Thanksgiving
Christmas),
indicating
cooking-related
activities
a
strong
source
monitored
residences.
Cerebral Cortex,
Journal Year:
2021,
Volume and Issue:
32(10), P. 2156 - 2169
Published: Sept. 8, 2021
Air
pollution
is
a
major
environmental
threat
to
public
health;
we
know
little,
however,
about
its
effects
on
adolescent
brain
development.
Exposure
air
co-occurs,
and
may
interact,
with
social
factors
that
also
affect
development,
such
as
early
life
stress
(ELS).
Here,
show
severity
of
ELS
fine
particulate
(PM2.5)
are
associated
volumetric
changes
in
distinct
regions,
but
uncover
regions
which
moderates
the
PM2.5.
We
interviewed
adolescents
events,
used
satellite-derived
estimates
ambient
PM2.5
concentrations,
conducted
longitudinal
tensor-based
morphometry
assess
regional
volume
over
an
approximately
2-year
period
(N
=
115,
ages
9-13
years
at
Time
1).
For
who
had
experienced
less
severe
ELS,
was
across
several
gray
white
matter
regions.
Fewer
were
observed
for
more
although
occasionally
they
opposite
direction.
This
pattern
results
suggests
many
moderate
largely
constrains
structural
Further
theory
research
needed
joint
brain.
Sensors,
Journal Year:
2022,
Volume and Issue:
22(7), P. 2755 - 2755
Published: April 2, 2022
Low-cost
particle
sensors
are
now
used
worldwide
to
monitor
outdoor
air
quality.
However,
they
have
only
been
in
wide
use
for
a
few
years.
Are
reliable?
Does
their
performance
deteriorate
over
time?
the
algorithms
calculating
PM2.5
concentrations
provided
by
sensor
manufacturers
accurate?
We
investigate
these
questions
using
continuous
measurements
of
four
PurpleAir
monitors
(8
sensors)
under
normal
conditions
inside
and
outside
home
1.5-3
A
recently
developed
algorithm
(called
ALT-CF3)
is
compared
two
existing
(CF1
CF_ATM)
Plantower
manufacturer
PMS
5003
PA-II
monitors.
Results.
The
CF1
lost
25-50%
all
indoor
data
due
part
practice
assigning
zero
below
threshold.
None
were
ALT-CF3
algorithm.
Approximately
92%
showed
precision
better
than
20%
algorithm,
but
approximately
45-75%
achieved
that
level
limits
detection
(LODs)
mostly
1
µg/m3,
3-10
µg/m3
percentage
observations
exceeding
LOD
was
53-92%
16-44%
At
low
found
many
homes,
appear
poorly
suited.