The document describes a study to identify unknown accelerants used in arson cases by analyzing burn debris. Activated charcoal strips were used to absorb vapors from burn debris heated in paint cans. The strips were then chemically extracted and run through gas chromatography-mass spectrometry (GCMS). Different heating methods of the debris were tested to vaporize burnt accelerants for absorption. The optimal method heated cans to 95°C for 4-5 hours, successfully identifying known accelerants like kerosene and lamp oil by comparing chromatograms to standards. This method then correctly identified an unknown accelerant as kerosene based on retention times and mass spectral data matching the kerosene standard.

1. RESEARCH POSTER PRESENTATION DESIGN © 2012
www.PosterPresentations.com
The
purpose
of
this
work
was
to
iden/fy
the
accelerant
used
in
a
possible
arson
case
from
the
burn
debris.
Through
the
use
of
ac/vated
charcoal
strips
and
the
gas
chromatograph/mass
spectrometer
(GCMS)
it
is
possible
to
iden/fy
an
unknown
accelerant.
The
ac/vated
charcoal
strips
absorbed
the
vapors
from
the
burn
debris
and
then
the
vapor
samples
were
extracted
using
a
solvent.
The
chromatogram
from
the
resul/ng
solu/on
was
then
compared
to
a
1%
standard
of
a
known
accelerant,
which
led
to
correct
iden/fica/on
of
the
unknown
accelerant
via
reten/on
/me
and
mass
spectral
informa/on.
Abstract
A
t-­‐shirt
was
put
into
a
burn
bucket
and
then
dowsed
with
an
accelerant.
The
t-­‐shirt
was
then
lit
on
fire
with
a
match
and
burned
for
around
15
minutes.
The
resul/ng
burn
debris
was
analyzed
by
first
puWng
the
debris
in
an
empty,
unlined
paint
can.
A
paper
clip
was
bent
at
a
90°angle
and
taped
to
the
paint
can’s
lid.
An
ac/vated
charcoal
strip(ACS)
was
then
aZached
to
the
end
of
the
paper
clip.
The
lid
was
then
secured
allowing
no
vapor
to
escape.
The
paint
can
containing
the
debris
and
ACS
were
heated
at
different
temperatures(table
1)
in
order
to
vaporize
the
burnt
accelerant.
Aer
the
the
ACS
adsorbed
the
accelerant’s
vapor
it
was
put
in
a
GC
vial
containing
1ml
of
methylene
chloride.
Aer
30
minutes
the
sample
was
ran
in
the
GCMS.
The
chromatograms
were
then
compared
to
1%
standards
with
respect
to
both
reten/on
/me
(obtained
by
measuring
total
ion
count
(or
TIC))
of
the
components
as
well
as
iden/fica/on
of
the
ions
based
in
the
mass
spectrum
in
order
to
iden/fy
the
accelerant
used
from
the
fire
debris.
Procedure
• Accelerants
(kerosene,
gasoline,
lamp
oil)
• T-­‐shirts
• Burn
Bucket
• Matches
• Fire
Ex/nguisher
• Unknown
Burn
Debris
• Unlined,
empty
gallon
paint
cans
• Scotch
Tape
• Unpainted,
uncoated
paperclips
• Albrayco
Technology
Ac/vated
Charcoal
Strips
(8x20
mm)
• Incubator
• Oven
• GC
Vials
• MicropipeZe
(P1000,P10)
• Methylene
Chloride,
99.5%
• Agilent
7820A
GC
• Agilent
5977E
Mass
Spectrometer
• Agilent
7693
Automa/c
Liquid
Sampler
Materials
Results
Setup
Discussion
In
order
to
find
a
method
that
correctly
iden/fies
accelerants
from
burn
debris
the
paint
cans
containing
the
burn
debris
and
an
ACS
were
heated
and
incubated
at
different
temps
for
different
amounts
of
/me.
To
test
the
different
methods(Table
1)
the
resul/ng
chromatogram
from
an
ACS
with
a
known
accelerant
was
compared
to
it’s
1%
standard.
Aer
incuba/ng
the
ACS
in
a
paint
can
with
burn
debris
for
24
hours
at
room
temperature
(method
1)
there
were
no
iden/fiable
peaks
produced
in
its
chromatogram.
The
next
aZempt
was
to
heat
the
paint
can
for
16
hours
at
65
°C
(method
2).
This
method
was
successful
in
iden/fying
the
known
accelerant
however,
when
aZemp/ng
to
repeat
the
experiment
with
this
method
no
iden/fiable
peaks
in
the
chromatograms
could
be
produced.
The
probable
success
for
this
method
was
due
to
a
large
amount
of
unburnt
accelerant
was
le
on
the
debris
allowing
the
ACS
to
easily
adsorb
the
vapor.
Since
that
method
was
not
repeatable
this
lead
to
the
final
method
of
hea/ng
the
paint
cans
at
95
°C
for
4-­‐5
hours(method
3).
This
method
produced
iden/fiable
chromatograms
when
compared
to
1%
standards.
In
figure
2
the
chromatogram
produced
by
the
kerosene
ACS
was
overlapped
with
the
1%
kerosene
solu/on’s
chromatogram.
When
comparing
both
chromatograms
peaks
with
regards
to
abundance
and
reten/on
/me
the
accelerant
can
be
iden/fied
correctly.
Using
this
method
again
for
lamp
oil
similar
results
were
produced
and
can
be
seen
in
figure
3.
Now
that
a
method
proved
to
successfully
iden/fy
known
accelerants
the
next
step
was
to
obtain
burn
debris
that
contained
an
unknown
accelerant
and
test
the
method
again.
The
resul/ng
chromatogram
from
the
unknown
was
then
compared
to
1%
standards.
The
unknown
accelerant
was
iden/fied
as
kerosene
and
the
comparison
of
chromatograms
can
be
seen
in
figure
4.
To
further
prove
the
unknown
was
kerosene
the
peaks
of
both
kerosene
1%
standard
and
the
unknown
at
5.134
minutes
mass
specs.
were
analyzed.
In
both
cases
the
mass
spec.
iden/fied
the
compound
to
be
ethylcyclohexane,
a
common
hydrocarbon
found
in
kerosene.
Future
DirecBons
Throughout
this
research
gasoline
was
never
iden/fiable
when
compared
to
it’s
1%
standard.
The
gasoline
ACS
never
provided
any
iden/fiable
peaks
on
it’s
chromatogram.
One
possible
reason
was
the
solvent
we
used,
methylene
chloride,
did
not
allow
the
gasoline
vapors
to
properly
desorb
from
the
ACS.
The
next
experiment
I
would
do
to
solve
this
problem
is
to
use
carbon
disulfide
as
the
solvent
when
desorbing
the
ACS.
Acknowledgements
I
would
like
to
thank
Dr.
Spudich
for
guiding
me
in
the
right
direc/on
throughout
this
research
project
and
supplying
me
with
resources
that
contained
answers
to
any
problems.
I
would
also
like
to
thank
Mr.
Pete
Kleine
for
guidance
with
GCMS
set
up
and
discussion
on
subs/tute
solvents
for
carbon
disulfide.
Kory
Clawson
IdenBficaBon
of
Accelerants
Used
in
Arson
Crime
Tape
Paper
Clip
Ac/vated
Charcoal
Strip
(ACS)
Burn
Debris
Paint
Can
Fig.
2
Fig.
3
Fig.
4
This
figure
shows
the
1%
kerosene
standard
chromatogram
overlapped
with
the
chromatogram
from
the
burn
debris
where
kerosene
was
used
as
the
accelerant.
This
figure
shows
the
1%
lamp
oil
standard
chromatogram
overlapped
with
the
chromatogram
from
the
burn
debris
where
lamp
oil
was
used
as
the
accelerant.
This
figure
shows
the
1%
kerosene
standard
chromatogram
overlapped
with
the
chromatogram
from
the
burn
debris
where
an
unknown
was
used
as
the
accelerant.
Conclusion
Using
this
method
it
is
possible
to
iden/fy
an
unknown
accelerant
used
in
an
arson
crime
through
the
use
of
ac/vated
charcoal
strips
and
gas
chromatograph/mass
spectrometer.
Table
1
Method
Temperature
IncubaBon
Time
Method
1
~25
°C
24
hours
Method
2
65
°C
16
hours
Method
3
95
°C
4-­‐5
hours
In
table
1
each
method
is
in
reference
to
a
paint
can
containing
burn
debris
and
an
ACS(Fig
1).
Fig.
1
Methods
Fig.
5A
Fig.
5B
Figure
5A
shows
a
comparison
of
the
MS
of
the
unknown
peak
circled
in
red
in
figure
4
to
ethylcyclohexane’s
MS.
Figure
5B
shows
the
actual
MS
of
ethylcyclohexane.