Atmospheric chemistry and physics,
Год журнала:
2024,
Номер
24(24), С. 14177 - 14190
Опубликована: Дек. 19, 2024
Abstract.
Secondary
organic
aerosols
(SOAs)
from
highly
volatile
compounds
(VOCs)
are
currently
not
well
represented
in
numerical
models
as
their
heterogeneous
formation
mechanisms
the
atmosphere
remain
unclear.
Based
on
smog
chamber
experiments,
here
we
investigated
yield
and
pathway
of
SOA
acetone
photochemical
reactions
under
low-NOx
conditions
presence
preexisting
haze
particles
((NH4)2SO4
NH4HSO4)
saline
mineral
(Na2SO4)
ammonia-rich
conditions.
Our
results
showed
that
acetone-derived
is
remarkably
enhanced
via
multiphase
these
seeds,
especially
for
particles.
We
found
aerosol
acidity
a
key
factor
controlling
pathways
SOA,
which
acids,
alcohol,
carbonyls
produced
dissolve
into
aqueous
phase
seeds
subsequently
esterify
and/or
oligomerize
SOAs
consist
larger
molecules
acidic
but
smaller
neutral
aerosols.
Moreover,
light
absorption
ability
formed
(NH4)2SO4
stronger
than
Na2SO4
particles,
ammonia,
due
to
N-containing
organics.
Through
comparison
with
methylglyoxal
(MGly),
total
2.8–8.2
times
irreversible
uptake
MGly,
suggesting
only
considering
MGly
precursor
will
probably
underestimate
role
global
production
since
abundantly
exists
troposphere.
Chemical Reviews,
Год журнала:
2023,
Номер
123(4), С. 1635 - 1679
Опубликована: Янв. 11, 2023
Organic
peroxides
(POs)
are
organic
molecules
with
one
or
more
peroxide
(−O–O−)
functional
groups.
POs
commonly
regarded
as
chemically
labile
termination
products
from
gas-phase
radical
chemistry
and
therefore
serve
temporary
reservoirs
for
oxidative
radicals
(HOx
ROx)
in
the
atmosphere.
Owing
to
their
ubiquity,
active
gas-particle
partitioning
behavior,
reactivity,
key
reactive
intermediates
atmospheric
multiphase
processes
determining
life
cycle
(formation,
growth,
aging),
climate,
health
impacts
of
aerosol.
However,
there
remain
substantial
gaps
origin,
molecular
diversity,
fate
due
complex
nature
dynamic
behavior.
Here,
we
summarize
current
understanding
on
POs,
a
focus
identification
quantification,
state-of-the-art
analytical
developments,
molecular-level
formation
mechanisms,
chemical
transformation
pathways,
well
environmental
impacts.
We
find
that
interactions
SO2
transition
metal
ions
generally
fast
PO
pathways
liquid
water,
lifetimes
estimated
be
minutes
hours,
while
hydrolysis
is
particularly
important
α-substituted
hydroperoxides.
Meanwhile,
photolysis
thermolysis
likely
minor
sinks
POs.
These
distinctly
different
fates,
such
reaction
OH
radicals,
which
highlights
need
understand
By
summarizing
advances
remaining
challenges
investigation
propose
future
research
priorities
regarding
fate,
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(15), С. 6736 - 6743
Опубликована: Апрель 2, 2024
Acidity
is
an
important
property
of
particulate
matter
(PM)
in
the
atmosphere,
but
its
association
with
PM
toxicity
remains
unclear.
Here,
this
study
quantitively
reports
effect
acidity
level
on
via
pH-control
experiments
and
cellular
analysis.
Oxidative
stress
cytotoxicity
potencies
acidified
samples
at
pH
1–2
were
up
to
2.8–5.2
2.1–13.2
times
higher
than
those
8–11,
respectively.
The
toxic
from
real-world
smoke
plumes
2.3
9.1–18.2
greater
5.6,
demonstrating
a
trend
similar
that
samples.
Furthermore,
impact
was
manifested
by
promoting
metal
dissolution.
dramatic
increase
2–3
orders
magnitude
water-soluble
content
dominated
variation
toxicity.
significant
correlation
between
sulfate,
value,
Fe,
IC20,
EC1.5
(p
<
0.05)
suggested
acidic
sulfate
could
enhance
dissolving
insoluble
metals.
findings
uncover
superficial
adverse
health
outcomes
epidemiological
research
highlight
control
wet
plume
emissions
mitigate
effects
acidity.
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(10), С. 4716 - 4726
Опубликована: Фев. 27, 2024
The
mechanism
and
kinetics
of
reactive
oxygen
species
(ROS)
formation
when
atmospheric
secondary
organic
aerosol
(SOA)
is
exposed
to
solar
radiation
are
poorly
understood.
In
this
study,
we
combined
an
in
situ
UV–vis
irradiation
system
with
electron
paramagnetic
resonance
(EPR)
spectroscopy
characterize
the
photolytic
ROS
aqueous
extracts
SOA
formed
by
oxidation
isoprene,
α-pinene,
α-terpineol,
toluene.
We
observed
substantial
free
radicals,
including
•OH,
superoxide
(HO2•),
radicals
(R•/RO•)
upon
irradiation.
Compared
dark
conditions,
radical
yield
was
enhanced
a
factor
∼30
for
•OH
2–10
emergence
radicals.
Total
peroxide
measurements
showed
decreases
contents
after
photoirradiation,
indicating
that
peroxides
can
be
important
source
A
liquid
chromatography
interfaced
high-resolution
mass
spectrometry
used
detect
number
form
adducts
spin
trap,
BMPO.
types
detected
photolysis
model
compounds
indicated
carbonyls
Norrish
type
I
mechanisms
plays
role
formation.
serves
as
driving
force
cloud
fog
processing
SOA.
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(19), С. 8194 - 8206
Опубликована: Апрель 29, 2024
Phenolic
compounds
are
largely
emitted
from
biomass
burning
(BB)
and
have
a
significant
potential
to
form
SOA
(Phc-SOA).
However,
the
toxicological
properties
of
Phc-SOA
remain
unclear.
In
this
study,
phenol
guaiacol
were
chosen
as
two
representative
phenolic
gases
in
BB
plumes,
water-soluble
components
their
generated
under
different
photochemical
ages
NOx
levels
investigated.
contribute
greatly
oxidative
(OP)
biomass-burning
SOA.
OH-adducts
(e.g.,
2-methoxyhydroquinone)
identified
(GSOA)
with
high
OP.
The
addition
nitro
groups
2,5-dimethyl-1,4-benzoquinone,
surrogate
quinone
compound
Phc-SOA,
increased
its
toxicity
both
(PSOA)
GSOA
vitro
human
alveolar
epithelial
cells
decreased
aging
terms
cell
death
cellular
reactive
oxygen
species
(ROS),
possibly
due
more
ring-opening
products
relatively
low
toxicity.
influence
was
consistent
between
ROS
for
but
not
PSOA,
indicating
that
production
does
necessarily
represent
all
processes
contributing
caused
by
PSOA.
Combining
acellular
assays
can
provide
comprehensive
understanding
aerosol
properties.
Environmental Science & Technology,
Год журнала:
2022,
Номер
56(23), С. 17029 - 17038
Опубликована: Ноя. 17, 2022
Oxidative
stress
mediated
by
reactive
oxygen
species
(ROS)
is
a
key
process
for
adverse
aerosol
health
effects.
Secondary
organic
aerosols
(SOA)
account
major
fraction
of
fine
particulate
matter,
and
their
inhalation
deposition
into
the
respiratory
tract
causes
formation
ROS
chemical
cellular
processes,
but
relative
contributions
are
hardly
quantified
link
to
oxidative
remains
uncertain.
Here,
we
superoxide
generation
9,10-phenanthrenequinone
(PQN)
isoprene
SOA
using
chemiluminescence
assay
combined
with
electron
paramagnetic
resonance
spectroscopy
as
well
kinetic
modeling.
We
also
applied
imaging
techniques
study
mechanism
release
damage
on
cell
membranes.
show
that
PQN
activate
NADPH
oxidase
in
macrophages
massive
amounts
superoxide,
overwhelming
aqueous
reactions
epithelial
lining
fluid.
The
activation
dose
2
orders
magnitude
lower
than
SOA,
suggesting
quinones
more
toxic.
While
higher
exposures
trigger
antioxidant
response
elements,
released
induce
membrane
through
lipid
peroxidation.
Such
mechanistic
quantitative
understandings
provide
basis
further
elucidation
effects
matter.
The Journal of Physical Chemistry A,
Год журнала:
2022,
Номер
126(40), С. 7361 - 7372
Опубликована: Окт. 4, 2022
Reactive
oxygen
species
(ROS)
and
environmentally
persistent
free
radicals
(EPFR)
play
an
important
role
in
chemical
transformation
of
atmospheric
aerosols
adverse
aerosol
health
effects.
This
study
investigated
the
effects
nitrogen
oxides
(NOx)
during
photooxidation
α-pinene
naphthalene
on
EPFR
content
ROS
formation
from
secondary
organic
(SOA).
Electron
paramagnetic
resonance
(EPR)
spectroscopy
was
applied
to
quantify
formation.
While
no
were
detected
SOA,
we
found
that
SOA
contained
about
0.7
pmol
μg-1
EPFR,
NOx
has
little
influence
concentrations
oxidative
potential.
α-Pinene
generated
under
low
conditions
form
OH
superoxide
aqueous
phase,
which
lowered
substantially
by
50-80%
for
high
conditions.
High-resolution
mass
spectrometry
analysis
showed
substantial
nitroaromatics
nitrates
a
environment.
The
modeling
results
using
GECKO-A
model
simulates
explicit
gas-phase
chemistry
radical
2D-VBS
treats
autoxidation
predicted
reduced
hydroperoxides
enhanced
due
reactions
peroxy
with
instead
their
HO2.
Consistently,
presence
resulted
decrease
peroxide
contents
potential
SOA.