Environmental Science & Technology,
Год журнала:
2022,
Номер
56(23), С. 16848 - 16856
Опубликована: Ноя. 17, 2022
Dehydrochlorination
is
one
of
the
main
(thus
far
discovered)
processes
for
aerobic
microbial
transformation
hexachlorocyclohexane
(HCH)
which
mainly
catalyzed
by
LinA
enzymes.
In
order
to
gain
a
better
understanding
reaction
mechanisms,
multi-element
compound-specific
stable
isotope
analysis
was
applied
evaluating
α-
and
γ-HCH
transformations
LinA1
LinA2
The
isotopic
fractionation
(εE)
values
particular
elements
(+)α-HCH
(εC
=
−10.8
±
1.0‰,
εCl
−4.2
0.5‰,
εH
−154
16‰)
were
distinct
from
(−)α-HCH
−4.1
0.7‰,
−1.6
0.2‰,
−68
10‰),
whereas
dual-isotope
patterns
almost
identical
both
enantiomers
(ΛC–Cl
2.4
0.4
2.5
0.2,
ΛH–C
12.9
14.9
1.1).
εE
−7.8
1.0‰
−7.5
0.8‰
(εC),
−2.7
0.3‰
−2.5
0.4‰
(εCl),
−170
25‰
−150
13‰
(εH),
respectively.
Similar
ΛC–Cl
(2.7
0.2
2.9
0.2)
observed
as
well
similar
(20.1
2.0
18.4
1.9),
indicating
mechanism
enzymes
during
transformation.
This
first
data
set
on
3D
enzymatic
dehydrochlorination,
gave
more
precise
characterization
bond
cleavages,
highlighting
potential
characterize
different
(e.g.,
dehydrochlorination
reductive
dehalogenation).
MethodsX,
Год журнала:
2022,
Номер
9, С. 101880 - 101880
Опубликована: Янв. 1, 2022
Compound-specific
isotope
analysis
(CSIA)
is
a
powerful
approach
to
evaluate
the
transformation
of
organic
pollutants
in
environment.
However,
application
CSIA
micropollutants,
such
as
pesticides,
remains
limited
because
appropriate
extraction
methods
are
currently
lacking.
Such
should
address
wide
range
pesticides
and
environmental
matrices,
while
recovering
sufficient
mass
for
reliable
without
inducing
stable
fractionation.
Here,
we
present
simple
carbon
nitrogen
different
matrices
six
commonly
used
herbicides,
i.e.,
atrazine,
terbutryn,
acetochlor,
alachlor,
butachlor,
S-metolachlor,
three
fungicides,
dimethomorph,
tebuconazole,
metalaxyl.
We
examined
potential
several
four
types
soils
or
sediments,
waters
aerial
root
plant
samples
multielement
(ME)-CSIA.•Pesticide
recoveries
varied
depending
on
physical
characteristics
matrix
properties
water
(77
87%),
soil
sediment
(35
82%),
(40
59%)
extraction.•The
tested
did
not
significantly
affect
signatures
(Δ(13C)
<0.9‰
Δ(15N)
<1.0‰).
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(13), С. 5996 - 6006
Опубликована: Март 20, 2024
2,4-Dinitroanisole
(DNAN)
is
a
main
constituent
in
various
new
insensitive
munition
formulations.
Although
DNAN
susceptible
to
biotic
and
abiotic
transformations,
many
environmental
instances,
transformation
mechanisms
are
difficult
resolve,
distinguish,
or
apportion
on
the
basis
solely
of
analysis
concentrations.
We
used
compound-specific
isotope
(CSIA)
investigate
characteristic
fractionations
(by
three
microbial
consortia
pure
cultures)
9,10-anthrahydroquinone-2-sulfonic
acid
[AHQS])
transformations
DNAN.
The
correlations
enrichment
factors
(ΛN/C)
for
had
range
values
from
4.93
±
0.53
12.19
1.23,
which
entirely
distinct
ΛN/C
reported
previously
alkaline
hydrolysis,
enzymatic
reduction
by
Fe2+-bearing
minerals
iron-oxide-bound
Fe2+,
UV-driven
phototransformations.
value
associated
with
AHQS
was
38.76
2.23,
within
albeit
mean
lower.
These
results
enhance
database
effects
accompanying
under
environmentally
relevant
conditions,
allowing
better
evaluation
extents
that
occur
soils,
groundwaters,
surface
waters,
marine
environment.
Environmental Science Processes & Impacts,
Год журнала:
2021,
Номер
23(11), С. 1791 - 1802
Опубликована: Янв. 1, 2021
Knowledge
of
direct
and
indirect
photodegradation
pesticides
associated
isotope
fractionation
can
help
to
assess
pesticide
degradation
in
surface
waters.
Here,
we
investigated
carbon
(C)
nitrogen
(N)
during
the
herbicides
atrazine
S-metolachlor
synthetic
agriculturally
impacted
waters
containing
nitrates
(20
mg
L-1)
dissolved
organic
matter
(DOM,
5.4
mgC
L-1).
Atrazine
were
quickly
photodegraded
by
both
processes
(half-lives
<5
<7
days,
respectively).
DOM
slowed
down
while
increased
rates.
The
analysis
transformation
products
showed
that
oxidation
mediated
hydroxyl
radicals
(HO˙)
predominated
photodegradation.
UV
light
(254
nm)
led
significant
C
N
fractionation,
yielding
isotopic
values
εC
=
2.7
±
0.3
0.8
0.1‰,
εN
2.4
-2.6
0.7‰
for
S-metolachlor,
respectively.
In
contrast,
under
simulated
sunlight
negligible
slight
emphasizing
effect
radiation
wavelengths
on
induced
Altogether,
these
results
highlight
importance
using
obtain
environmentally-relevant
distinguish
other
dissipation
pathways
