Environmental Science & Technology,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 27, 2024
Biomass
burning
is
an
important
source
of
brown
carbon
(BrC)
aerosols,
which
influence
climate
by
affecting
the
Earth's
radiative
balance.
However,
transformation
pathways
BrC
chromophores,
especially
in
presence
photochemically
active
species,
such
as
nitrate,
are
not
well
understood.
In
this
study,
nitrate-mediated
aqueous-phase
photooxidation
three
typical
chromophores
from
biomass
was
investigated,
including
4-nitrocatechol,
3-nitrosalicylic
acid,
and
3,4-dinitrophenol.
Variations
nitrate
concentrations,
pH,
temperatures
were
systematically
examined
to
assess
their
impacts
on
apparent
photolysis
rates
these
chromophores.
The
results
show
that
increasing
concentrations
significantly
enhances
3–3.5
times
compared
nitrate-free
conditions.
Also,
a
temperature
rise
0
30
°C
increases
factor
1.3–2.5
for
effect
pH
varies
among
depending
substituents
positions
benzene
ring.
High-resolution
mass
spectrometric
analysis
suggests
initiates
with
addition
nitro
and/or
hydroxyl
groups
ring,
followed
ring-opening
reaction
formation
smaller,
highly
oxygenated
molecules
formic
glyoxylic
malonic
nitropropanoic
acid.
This
study
highlights
key
role
BrC,
altering
aging
shortening
atmospheric
lifetimes
BrC.
These
particular
importance
better
understanding
its
forcing,
given
increase
fraction
aerosols
China
recent
years.
Aerosol Science and Technology,
Год журнала:
2024,
Номер
58(10), С. 1093 - 1113
Опубликована: Июль 24, 2024
Exposure
to
biomass-burning
particulate
matter
(PM)
is
associated
with
various
adverse
health
effects,
including
respiratory
and
cardiovascular
conditions,
cancer,
systemic
effects.
Multiple
mechanisms
underlying
PM
toxicity
components
derived
from
biomass
burning
elicit
harmful
such
as
reactive
oxygen
species
(ROS)
generation,
inflammation,
genotoxicity,
tissue-specific
damage.
Specific
compounds
or
families
of
present
in
PM,
polyaromatic
hydrocarbons
(PAHs)
their
derivatives,
have
been
identified
key
contributors
the
observed
Their
roles
oxidative
stress,
DNA
damage,
cell
death
elucidated
organs,
lungs,
liver,
kidneys,
brain,
providing
valuable
insights
into
biological
influence
biomass-burning-related
diseases.
Current
knowledge
impact
highlights
imperative
need
for
further
research
understand
implications
this
environmental
challenge
importance
mitigating
effects
increased
exposure
pollution
protect
well-being
exposed
populations
worldwide.
This
review
focuses
on
crucial
stress
inflammation
mediating
triggered
by
aerosols.
It
examines
aspects
health-related
impacts
emissions,
particularly
those
components.
The
consequences
populations,
emphasizing
specific
biochemical
responses,
contributions
mechanisms,
responsible
these
Atmospheric chemistry and physics,
Год журнала:
2024,
Номер
24(14), С. 8397 - 8411
Опубликована: Июль 26, 2024
Abstract.
Carbonyls
have
an
important
effect
on
atmospheric
chemistry
and
human
health
because
of
their
high
electrophilicity.
Here,
high-throughput
screening
carbonyl
molecules
in
complex
aerosol
samples
was
achieved
by
combining
targeted
derivatization
with
non-targeted
analysis
using
Fourier
transform
ion
cyclotron
resonance
mass
spectrometry
(FT-ICR
MS).
Results
showed
that
water-soluble
organic
matter
(WSOM)
PM2.5
contains
a
large
variety
carbonyls
(5147
total),
accounting
for
17.6
%
all
identified
molecules.
Compared
non-carbonyl
molecules,
are
more
abundant
winter
than
summer
unique
molecular
composition
chemical
parameters.
For
the
first
time,
significant
positive
correlation
found
between
abundance
dithiothreitol
(DTT)
activities
WSOM,
elimination
group
remarkably
reduced
DTT
activities,
highlighting
pivotal
role
determining
oxidative
potential
(OP)
aerosol.
Among
various
oxidized
aromatic
compounds
containing
produced
contributed
to
enhancement
activity,
which
could
be
used
as
markers
stress.
This
study
improves
our
understanding
diversity
environmental
effects
carbonyls,
emphasizing
need
strategies
mitigate
risks
associated
carbonyl-rich
aerosols.
Abstract.
Water-soluble
components
have
significant
contribution
to
the
oxidative
potential
(OP)
of
atmospheric
fine
particles,
while
our
understanding
their
relationship
is
still
limited.
In
this
study,
water-soluble
OP
levels
in
wintertime
PM2.5
south
and
north
Beijing,
representing
difference
sources,
were
measured
with
dithiothreitol
(DTT)
assay.
The
volume
normalized
DTT
(DTTv)
(3.5
±
1.2
nmol
min-1
m-3)
was
comparable
that
(3.9
0.9
m-3),
mass
(DTTm)
(65.3
27.6
pmol
μg-3)
almost
twice
(36.1
14.5
μg-3).
both
DTTv
better
correlated
soluble
elements
instead
total
elements.
north,
(mainly
Mn,
Co,
Ni,
Zn,
As,
Cd
Pb)
organic
compounds,
especially
light-absorbing
compounds
(also
known
as
brown
carbon),
had
positive
correlations
DTTv.
However,
south,
mainly
related
Fe
Pb.
sources
further
resolved
using
matrix
factorization
(PMF)
model.
Traffic-related
emissions
(39.1
%)
biomass
burning
(25.2
main
traffic-related
(>
50
contributed
most
north.
Our
results
indicate
vehicle
emission
important
contributor
Beijing
ambient
suggest
more
study
needed
understand
intrinsic
between
light
absorbing
compounds.
Dark
aqueous-phase
reactions
involving
the
nitrosation
and
nitration
of
aromatic
organic
compounds
play
a
significant
role
in
production
light-absorbing
carbon
atmosphere.
This
process
constitutes
crucial
aspect
tropospheric
chemistry
has
attracted
growing
research
interest,
particularly
understanding
mechanisms
governing
nighttime
between
phenols
nitrogen
oxides.
In
this
study,
we
present
new
findings
concerning
rapid
dark
containing
electron-donating
groups
inorganic
nitrite
acidic
aqueous
solutions
with
pH
levels
<3.5.
reaction
generates
substantial
amount
nitroso-
nitro-substituted
phenolic
compounds,
known
for
their
properties
toxicity.
experiments
utilizing
various
substituted
phenols,
demonstrate
that
rates
depend
on
electron
cloud
density
benzene
ring,
indicative
an
electrophilic
substitution
mechanism.
Control
theoretical
calculations
indicate
nitrosonium
ion
(NO
Atmospheric chemistry and physics,
Год журнала:
2024,
Номер
24(23), С. 13219 - 13230
Опубликована: Ноя. 29, 2024
Abstract.
Water-soluble
components
significantly
contribute
to
the
oxidative
potential
(OP)
of
atmospheric
fine
particles
(PM2.5),
but
our
understanding
water-soluble
PM2.5
OP
and
its
sources,
as
well
relationship
with
components,
is
still
limited.
In
this
study,
levels
in
wintertime
south
north
Beijing,
representing
difference
were
measured
dithiothreitol
(DTT)
assay.
The
volume-normalized
DTT
(DTTv)
(3.5±1.2
nmol
min−1
m−3)
was
comparable
that
(3.9±0.9
m−3),
while
mass-normalized
(DTTm)
(65±28
pmol
µg−3)
almost
twice
(36±14
µg−3).
both
DTTv
better
correlated
soluble
elements
instead
total
elements.
north,
(mainly
Mn,
Co,
Ni,
Zn,
As,
Cd
Pb)
organic
compounds,
especially
light-absorbing
compounds
(also
known
brown
carbon),
had
positive
correlations
DTTv.
However,
south,
mainly
related
Fe
Pb.
sources
further
resolved
using
matrix
factorization
(PMF)
model.
Traffic-related
emissions
(39
%)
biomass
burning
(25
main
traffic-related
(>50
contributed
most
north.
Our
results
indicate
vehicle
emission
an
important
contributor
Beijing
ambient
suggest
more
study
needed
understand
intrinsic
between
compounds.
