Perfluoroalkyl
acids
(PFAAs)
are
a
class
of
per-
and
polyfluoroalkyl
substances
(PFAS)
that
not
known
to
degrade,
mobile
in
groundwater,
highly
regulated.
PFAAs
can
be
generated
by
the
transformation
certain
PFAS
compounds
called
precursors.
A
semi-analytical/numerical
groundwater
model
considers
matrix
diffusion
was
calibrated
field
data
at
site
contain
both
their
respective
precursor
compounds.
The
modeling
effort
considered
four
key
PFAAs:
perfluorooctane
sulfonate
(PFOS),
perfluorooctanoic
acid
(PFOA),
perfluorohexane
(PFHxS),
perfluorobutane
(PFBS).
Individual
were
grouped
together
according
ability
transform
into
one
these
PFAAs.
Calibrated
results
show
PFOA,
PFHxS,
PFBS
resulted
concentrations
about
order
magnitude
greater
than
simulations
did
consider
transformation.
In
contrast,
PFOS
substantially
affected
due
high
source
zone
compared
its
first
half-lives
ranged
from
0.14
1.73
years,
retardation
factors
for
precursors
larger
2
6.
Environmental Science & Technology,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 7, 2025
The
application
of
aqueous
film-forming
foams
(AFFFs)
has
caused
considerable
per-
and
polyfluoroalkyl
substances
(PFAS)
pollution
in
the
environment.
Soil
serves
as
a
long-term
source
PFAS
for
adjacent
groundwater
surface
water,
but
lack
extractable
organofluorine
(EOF)
mass
balance
data
AFFF-impacted
soils
may
lead
to
an
underestimation
contamination.
This
study
analyzed
ten
soil
samples
from
three
sites
Sweden,
using
alkaline
extraction
followed
by
acidic
extraction.
fractions
were
subjected
further
cleanup
separately
target,
suspect
screening,
EOF
analysis
evaluate
efficiencies
different
reveal
remaining
unknown
soils.
Total
target
concentrations
ranged
33.0
2.40
×
104
ng/g
dry
weight.
Thirty-six
identified
screening.
Considerable
amounts
zwitterionic
cationic
(up
58%)
fraction,
while
>95%
anionic
found
fraction.
was
conducted
on
first
time.
high
proportion
unexplained
65%)
indicated
necessity
future
investigation
comprehensively
understand
their
fate
risk.
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(17), С. 7480 - 7492
Опубликована: Апрель 19, 2024
Microbial
transformation
of
per-
and
polyfluoroalkyl
substances
(PFAS),
including
fluorotelomer-derived
PFAS,
by
native
microbial
communities
in
the
environment
has
been
widely
documented.
However,
few
studies
have
identified
key
microorganisms
their
roles
during
PFAS
biotransformation
processes.
This
study
was
undertaken
to
gain
more
insight
into
structure
function
soil
that
are
relevant
biotransformation.
We
collected
16S
rRNA
gene
sequencing
data
from
8:2
fluorotelomer
alcohol
6:2
sulfonate
conducted
microcosms
under
various
redox
conditions.
Through
co-occurrence
network
analysis,
several
genera,
Variovorax,
Rhodococcus,
Cupriavidus,
were
found
likely
play
important
fluorotelomers.
Additionally,
a
metagenomic
prediction
approach
(PICRUSt2)
functional
genes,
6-oxocyclohex-1-ene-carbonyl-CoA
hydrolase,
cyclohexa-1,5-dienecarbonyl-CoA
hydratase,
fluoride-proton
antiporter
gene,
may
be
involved
defluorination.
pioneers
application
these
bioinformatics
tools
analysis
biotransformation-related
data.
Our
findings
serve
as
foundational
reference
for
investigating
enzymatic
mechanisms
defluorination
facilitate
development
efficient
consortia
and/or
pure
strains
Aqueous
film-forming
foam
(AFFF)
is
a
targeted
product
for
liquid
fuel
fires
and
has
the
benefits
of
long
storage
period
high
fire
extinguishing
efficiency.
However,
because
toxicity
bioaccumulation
core
raw
material's
long-chain
fluorocarbon
surfactant,
traditional
AFFF
being
phased
out.
For
this
reason,
three
efficient
AFFFs
(F-1,
F-2,
F-3;
more
details
in
Table
2)
were
designed
using
anionic
surfactants
(PBAF)
with
branched
C6
perfluorinated
chains,
hexadecyltrimethylammonium
bromide
(CTAB),
dodecyl
dimethyl
betaine
(BS-12)
as
materials.
Through
comparison,
F-1
shows
excellent
foaming
ability
(initial
height
86
mm)
stability
(25%
drainage
time
234
s).
Moreover,
exhibited
resistance
performance:
was
33
s,
831
s.
This
means
that
enormous
firefighting
potential
can
serve
alternative
to
AFFF.
