Fate and degradation of methoxychlor in a contaminated aquifer: insights from dual carbon-chlorine isotope analysis and isomeric fraction
Journal of Hazardous Materials,
Год журнала:
2025,
Номер
488, С. 137447 - 137447
Опубликована: Янв. 29, 2025
Язык: Английский
Role of membrane porosity in passive sampling of aquatic contaminants for stable isotope analysis: enhancement of analyte accumulation rates and selectivity
Analytical and Bioanalytical Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 31, 2025
Abstract
Compound-specific
isotope
analysis
(CSIA)
is
a
potent
method
for
illustrating
the
in
situ
degradation
of
aquatic
contaminants.
However,
its
application
to
surface
and
groundwater
hindered
by
low
contaminant
concentrations,
typically
nanogram-per-litre
range,
requiring
processing
large
water
volumes.
Polar
organic
chemical
integrative
samplers
(POCIS)
have
shown
promising
results
when
combined
with
CSIA,
yet
their
extended
deployment
time
accumulate
sufficient
analyte
mass
remains
major
limitation.
In
our
study,
we
addressed
this
issue
increasing
pore
size
polyethersulfone
membrane
(PES)
from
0.1
8
$$\upmu
$$
μ
m.
This
resulted
significant
increases
accumulation
rates
atrazine
(3.5-fold),
S-metolachlor
(3.4-fold),
boscalid
(3.0-fold).
Importantly,
larger
sizes
did
not
compromise
isotopic
integrity,
$$\Delta
\delta
^{13}$$
Δ
δ
13
C
$$\le
+0.4\pm
0.1$$
≤
+
0.4
±
0.1
‰
^{15}$$
15
N
-0.6\pm
0.4$$
-
0.6
‰,
both
within
accepted
uncertainties.
Additionally,
observed
an
enhanced
selectivity
pores
towards
target
analytes
over
humic
acids,
whereas
no
increase
(bio)fouling
potential
was
detected
m
membrane,
as
demonstrated
gravimetric
analysis,
SEM
measurements,
rates,
ratios
fouled
unfouled
POCIS.
Our
findings
show
that
reduces
expedites
required
gas
chromatography
ratio
spectrometry,
offering
expand
CSIA
low-concentration
pesticide
field.
Graphical
abstract
Язык: Английский
Insight into Imidacloprid Degradation through Compound Specific Carbon Isotope Analysis and High-Resolution Mass Spectrometry
ACS ES&T Water,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 6, 2024
The
insecticide
imidacloprid
(IMI)
is
an
ubiquitous
environmental
contaminant.
This
study
presents
approach
to
investigate
its
degradation
through
the
combined
use
of
compound-specific
stable
carbon
isotope
analysis
and
high-resolution
mass
spectrometry
(HRMS).
It
demonstrates
how
ratio
HRMS
product
can
complement
each
other.
photolysis
by
simulated
sunlight,
UV–C
(λ
=
254
nm),
alkaline
hydrolysis
all
exhibited
distinguishable
enrichment
factors
(εC).
largest
fractionation
observed
during
at
pH
12
30
°C
(εC
−3.9
±
0.4‰).
confirms
that
only
one
atom
in
a
reactive
position,
allowing
AKIE
calculation
−34.1
3.7‰).
Carbon
were
not
significantly
affected
dissolved
oxygen
content
or
pH.
Irradiation
did
result
significant
enrichment,
whereas
experiments
with
sunlight
yielded
εC
values
between
−1.1
0.1
−1.4
0.1‰.
was
hypothesized
increased
contribution
indirect
led
isotopic
enrichment.
Finally,
we
demonstrate
developed
method
be
used
determine
fingerprint
veterinary
flea
control
products.
Язык: Английский