Since
2013,
stringent
clean
air
initiatives
have
significantly
reduced
atmospheric
pollutant
emissions
in
China,
improving
quality
and
altering
the
spatiotemporal
patterns
of
pollution.
Utilizing
fine
particulate
matter
(PM2.5)
its
chemical
composition
data
from
2000
to
2023,
we
observed
a
reduction
disparity
PM2.5
concentrations
between
urban
nonurban
areas.
This
is
linked
stricter
emission
controls
areas
relocation
some
sources
However,
specific
constituents
driving
factors
behind
these
changes
remain
be
fully
elucidated.
By
analyzing
proportions
components
major
cities
such
as
Beijing,
Shanghai,
Guangzhou
their
surrounding
areas,
found
that
narrowing
gap
regions
associated
with
convergence
organic
(OM)
both
results
varying
strategies
tailored
distinct
characteristics
pollution
China.
Coordinated
governance
should
considered,
along
implementation
integrated
control
mitigation
measures
for
multiple
pollutants
further
enhance
Environment International,
Год журнала:
2025,
Номер
197, С. 109329 - 109329
Опубликована: Фев. 14, 2025
Transformed
from
p-phenylenediamines
(PPDs)
antioxidant,
PPD-derived
quinones
(PPD-Qs)
have
recently
been
recognized
as
emerging
contaminants
due
to
their
potential
negative
impacts
on
the
environment
and
human
health.
While
there
measurements
of
airborne
PPD-Qs,
size
distribution
PPD-Qs
impact
particle
PPD
transformation
chemistry
remain
largely
unknown.
Here,
through
atmospheric
particles
in
three
megacities
China
(Beijing,
Xi'an,
Hefei),
we
find
that
are
widely
distributed
these
cities.
Further
analysis
size-fractioned
Hefei
indicates
48
%
reside
coarse
particles.
Given
previous
studies
mainly
focus
measurement
fine
particles,
previously
reported
PPD-Q
concentrations
corresponding
exposure
dosages
likely
be
significantly
underestimated.
Furthermore,
ratio
concentration
(PPD-Q/PPD)
for
with
range
0.056
-
0.1
μm
is
up
3
times
higher
than
10
18
μm,
highlighting
key
role
determining
oxidation
reactivity
PPDs.
Model
simulations
reveal
a
size-dependent
pattern
estimated
particulate
body.
In
addition,
also
demonstrate
can
induce
formation
cellular
reactive
oxygen
species,
suggesting
they
may
pose
risks
Overall,
our
results
emphasize
importance
considering
effect
when
evaluating
reaction
risk
PPD-Qs.
