Rhonda,

As
per
our
recent
phone
discussion,
I
am
forwarding
you
an
email
sent
by
our
commercial
lab
concerning
the
problems
with
MPD
analysis.

Please
contact
me
if
you
have
any
questions.

Regards,

Rick
Vickery
DuPont
Chambers
Works
(
856)
540­
3285
­­­­­
Forwarded
by
Richard
S
Vickery/
AE/
DuPont
on
08/
26/
2005
12:
02
PM
­­
­­­

cjneslund@
lancast
erlabs.
com
To
08/
25/
2005
04:
17
Richard
S
Vickery/
AE/
DuPont@
DuPont
PM
cc
Subject
MPD
Analysis
Rick,

This
is
in
response
to
your
request
for
a
description
of
our
difficulties
in
trying
to
analyze
for
phenylenediamine
isomers.
Historically,
we
have
analyzed
for
1,4­
phenylenediamine
(
1,4­
PDA)
along
with
a
host
of
other
semivolatile
compounds
in
your
secondary/
tertiary
sludge.
Typically
this
data
is
highly
qualified
and
commented
on
owing
to
the
following
difficulties
associated
with
analyzing
for
1,4­
PDA;

1)
We
have
observed
that
when
1,4­
PDA
is
in
calibration
standard
mixes
with
the
other
large
list
of
semivolatile
compounds
that
we
analyze
for,
the
1,4­
PDA
degrades
rapidly.
Typically
when
in
solution
with
the
many
other
compounds
1,4­
PDA
is
only
stable
for
a
day
or
two.
Therefore,
we
run
a
separate
1,4­
PDA
calibration
that
has
only
1,4­
PDA
and
the
associated
internal
standards
in
it.
2)
The
recovery
for
1,4­
PDA
in
LCS's
or
MS/
MSD's
is
predictably
poor.
This
is
also
evidenced
by
the
fact
that
our
MDL/
LOQ
for
1,4­
PDA
are
quite
high.
The
MDL
is
determined
using
the
7
replicate
technique
dictated
in
40
CFR,
Part
136,
which
is
really
a
measure
of
precision.
Poor
precision
(
reproducibility)
along
with
poor
recovery
results
in
high
MDLs.
3)
Since
we
run
a
separate
calibration
curve
for
1,4­
PDA,
we
can
get
a
decent
curve
fit
calibrating
from
5
ug/
ml
to
120
ug/
ml.
However,
due
to
the
poor
recovery
of
1,4­
PDA
we
have
to
spike
it
into
QC
samples
at
1000
ug/
ml(
everything
else
is
spiked
at
100
ug/
ml)
to
even
see
10%
or
15%,
which
doesn't
usually
happen.

Therefore,
when
you
first
approached
us
about
analyzing
for
1,3­
PDA,
we
didn't
want
to
do
anything
with
it
if
we
were
going
to
have
to
analyze
for
it
the
same
way
we
currently
do
for
1,4­
PDA.
Currently,
for
your
secondary/
tertiary
sludge
we
use
3550B
for
the
extraction
(
sonic
probe
extraction)
and
8270C
for
the
analysis
(
GC/
MS
­
quadrapole
in
EI
mode).
This
endeavor
would
have
just
resulted
in
more
highly
qualified
data
from
us.
While
we
have
not
done
the
formal
extraction
and
analysis
studies
for
1,3­
PDA
and
1,2­
PDA,
our
expectation
based
on
experience
with
1,4­
PDA
and
the
chemical
similarities
was
that
1,3­
PDA
and
1,2­
PDA
would
perform
just
as
poorly.

For
your
most
recent
secondary/
tertiary
sludge
sample,
we
did
obtain
a
standard
of
1,3­
PDA
and
prepared
a
100
ug/
ml
solution
to
analyze
along
side
the
extract
for
your
sludge
sample.
We
used
the
retention
time
from
the
analysis
of
the
1,3­
PDA
standard
as
a
reference
point
and
did
a
library
search
of
the
sludge
for
1,3­
PDA.
We
did
not
detect
any
1,3­
PDA
in
the
sludge.
It
is
difficult
to
set
a
reporting
limit
for
this,
but
certainly
rationalization
would
indicate
that
it
would
be
on
the
order
of
what
is
observed
for
1,4­
PDA
using
the
full
method.

As
a
part
of
the
analysis
for
1,3­
PDA
in
your
sludge
using
the
library
search,
we
were
able
to
see
that
based
on
a
relative
retention
time
basis,
we
should
be
able
to
chromatographically
separate
1,3­
PDA
from
1,4­
PDA
using
the
conditions
of
the
8270
analysis.
I
am
not
sure
what
we
would
run
into
with
1,2­
PDA.
However,
we
would
still
feel
that
going
forward
if
you
are
required
to
analyze
for
all
three
isomers
we
would
be
better
off
looking
into
setting
up
a
technique
that
addresses
the
extraction
challenges
of
the
phenylenediamine
isomers
as
well
as
the
stability
and
chromatographic
challenges.

If
you
have
any
further
questions,
please
call.

Sincerely,

Chuck
Neslund
Manager,
GC/
MS
Semivolatiles
Lancaster
Laboratories
717­
656­
2300,
x1819
cjneslund@
lancasterlabs.
com
