3M
3M
General
Offices
August
1,
2003
3M
Center
St.
Paul,
MN55
144­
1000
12733
1110
VIA
FEDERAL
EXPRESS
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
EPA
East,
Room
6428
1201
Constitution
Avenue,
MW
WashingtonDC
20460
Dear
Sir
or
Madam:

During
the
July
9,
2003
meeting
ofthe
Fluoropolymers
Technical
Workgroup
there
was
a
request
for
information
on
the
physical/
chemical
properties
of
PFOA.
This
information
is
attached.
In
addition,
a
summary
ofenvironmental
fate
study
results
is
included
in
the
attachment
to
augment
the
understanding
of
environmental
behavior
ofthis
substance.

This
document
should
be
considered
an
addition
to
the
P­
Chem
properties
for
fluoropolymers
data
request
made
in
Item
2
on
page
11
ofthe
Preliminary
Framework
document
published
by
EPA
on
May
20,
2003.
A
reference
ofthis
submittal
should
be
placed
in
the
Electronic
Docket
OPPT­
2003­
00
12.

Sincerely,

/~

.
 
`
cc:
Mary
Dominiak
 
Room
4410
Michael
A.
Santoro
Director
ofEnvironmental,
Health
Safety
and
Regulatory
Affairs
3M/
Building
236­
1B­
lO
St.
Paul,
MN
55144
651­
733­
6374
(
phone)
651­
733­
1958
(
fax)
George
H.
Millet
Director
­
Quality,
Environmental,
Health
&
Safety
Dyneon
LLC,
3M
Company
6744
33rd
Street
N.
St.
Paul,
MN
55128
651­
733­
5637
(
office)
651­
737­
9637
(
fax)

Attachment
PERFLUOROOCTANOIC
ACID
Physiochemical
Properties1
and
Environmental
Fate
Data
PERFLUOROOCTANOIC
ACID
­
PHYSICAL
AND
CHEMICAL
PROPERTIES'

Chemical
Identity
Chemical
Name:
Perfluorooctanoic
Acid
Molecular
formula:
C8
H
F15
02
Structural
fonnula:
F­
CF2­
CF2­
CF2­
CF2­
CF2­
CF2­
CF2­
C(=
O)­
X,
The
free
acid
and
some
common
derivatives
have
the
following
CAS
numbers:
The
perfluorooctanoate
anion
does
not
have
a
specific
CAS
number.
Free
Acid
(
X
=
OM+;
M
=
H)
[
335­
67­
1]
Ammoniurn
Salt
(
X
=
OM+;
M=
NB4)
[
3825­
26­
1]
Sodium
Salt
(
X
=
OM+;
M
=
Na)
[
335­
95­
5]
Potassium
Salt
(
X
=
OM+;
M
=
K)
[
2395­
00­
8]
Silver
Salt
(
X
=
OM
±
;
M
=
Ag)
[
335­
93­
3]
Acid
Fluoride
(
X
=
F)
[
335­
66­
0]
Methyl
Ester
(
X
=
CH3)
[
376­
27­
2]
Ethyl
Ester
(
X
=
CH2­
CH3)
[
3108­
24­
5]
Synonyms:
1­
Octanoic
acid,
2,2,3,3,4,4,5,5,6,6,7,7,8,8,8­
pentadecafluoro­
PFOA
Ammonium
perfluorooctanoate
(
APFO)
is
the
Fluorinated
Polymerization
Aid
(
FPA)
most
commonly
used
in
the
production
ofmany
fluoropolymers
and
fluoroelastomers.
APFO
has
several
synonyms
including
C­
8
acid,
FC
143,
and
perfluoro­
ammonium
octanoate.
Thefree
acid,
perfluorooctanoic
acid,
is
often
calledPFOA.
A
more
complete
description
ofphysical
and
other
propertiesofthis
and
other(
FPA)
s
may
be
found
in
Fluorinated
Surfactants2.

Thermal
Behavior
Perfluorooctanoic
acid
has
a
fairly
low
melt
point
of45
 
50
°
C,
with
slight
sublimation
reported
to
occur
at40
°
C
~.
The
reported
vapor
pressure
ofPFOA,
10
mm
Hg,
appears
high
for
a
low
melting
solid
when
compared
to
other
low
melting
solids
(
chloroacetic
acid:
solid;
MP
61
to
63
IC;
BP
=
189
IC;
VP
0.1
kFa
(
0.75
mm
Hg)
@
20
IC;
NIOSH),
but
is
consistent
with
other
perfluorinated
compounds
with
similar
boiling
points
(
perfluorobutanoic
acid
BP
=
120
IC,
VP
10
mm
Hg
@
20
IC)
~.
The
vapor
pressure
was
measured
at
an
elevated
temperature
(
inadvertently
omitted
from
the
report).
Perfluorooctanoic
acid
is
typically
handled
as
a
liquid
at
65
/
C
~.

While
it
maybe
expected
that
conversion
ofthePFOA
acid
toa
salt
should
reduce
its
volatility,
animonium
perfluorooctanoate,
the
most
commonly
used
salt
ofPFOA,
shows
volatility
at
fairly
low
temperatures.
The
vapor
pressure
ofammoniumperfluorooctanoate
(
APFO)
was
reported
to
be
approximately
7
X
10~
mm
Hg
at
20
°
C.
6
A
study
ofweight
loss
behavior
by
thermogravimetric
analysis
ofvarious
salts
ofperfluoroi
ctanoic
acid
illustrates
the
differences
hi
thermal
behavior
`~.
For
example,
the
ammonium
saltbegan
to
show
loss
of
sample
weight
in
the
50­
100
°
Crange
(
20%
loss
under
the
conditions
used
at
167
°
C),
while
the
sodium
salt
did
not
show
weight
loss
until
about
the
200­
250
°
Crange
(
20%
weight
loss
at
298
°
C).
The
ammonium
salt
begins
to
sublimate
at
13
0
°
Cwith
20%
of
the
weight
ofthe
sample
t
lost
by
169
°
C.
Other
salts
(
Cs,
K,
Ag,
Pb,
Li)
do
not
demonstrate
similar
weight
loss
until
23
7
°
Corhigher.
8
Decomposition
ofdifferent
salts
produces
perfluoroheptene
(
loss
ofmetal
fluoride
and
carbon
dioxide).
This
occurs
at
320
°
Cfor
the
sodium
salt
and
at
25
0­
290
/
C
for
the
silver
salt
~.

Behavior
in
Water
As
expected,
the
solubility
ofperfluorooctanoic
acid
and
other
salts
is
complex
and
can
involve
the
formation
ofmicellar
solutions
and
liquid
crystal
phases.
Phase
diagrams
havebeenpublished
for
ammonium
perfluorooctanoate.
8
The
free
acid
of
PFOA
is
expected
to
completely
dissociate
in
water.
In
aqueous
solutions,
individual
molecules
ofPFOA
anion
loosely
associate
on
the
water
surface
and
partition
between
the
air
/
water
interface.
Several
reports
note
that
PFOA
salts
self­
associate
at
the
surface,
but
with
agitation
they
disperse
and
micelles
form
at
higher
concentrations9,
10
&
hI°
Water
solubility
has
been
reported
for
PFOA,
but
it
is
unclear
whether
these
values
are
for
a
microdispersion
ofmicelles,
rather
than
true
solubility.

Due
to
these
same
surface­
active
properties
ofPFOA,
and
the
test
protocol
for
the
OECD
shake
flask
method,
PFOA
is
anticipated
to
form
multiple
layers
in
octanol/
water
Therefore,
an
n­
octanol/
water
partition
coefficient
cannot
be
determined.

The
PFOA
derivative
having
the
greatest
use
is
the
ammonium
salt
(
APFO;
CAS
No.
3
825­
26­
1).
The
water
solubility
ofAPFO
has
been
inconsistently
reported.
One
3M
study
reported
the
water
solubility
ofAPFO
to
be>
10%.
It
was
noted
in
an
earlier
study
that
at
concentrations
of20
gIL,
the
solution
"
gelled"
(
3M,
1979).
This
latter
result
seems
surprising
low
for
a
salt
in
light
ofApollo
Scientific
selling
a
31%
aqueous
solution
ofAPFO.
One
author
reported
the
APFO
partition
coefficient
log
P~,
5.
Another
author
reported
an
estimated
APFO
log
P~=
­
0.9.
This
value
might
not
be
accurate
due
to
the
estimation
method
used
12
Again,
the
anticipated
formation
of
an
emulsified
layer
betweenthe
octanol
and
water
surface
interface
would
make
determination
of
log
K0~
impossible.

Physicochemical
Properties
The
available
physicochemical
properties
for
the
PFOA
free
acid
are:
Molecular
weight:
414~
Melting
point:
45
 
50
IC~
Boiling
point:
189
 
192
/
C
/
736
mm
Hg5
Vapor
pressure:
10
mm
Hg@
25
/
C
(
approx.)
(
Exfluor
MSDS)
Water
solubility:
3.4
g/
L
(
telomeric
[
MP
34
/
C
ref.
0.01
­
0.02
mol/
L
~
4
­
8
g/
L)
(
MSDS
from
Merck,
Fischer,
and
Chinameilan
Internet
sites)
pKa:
2.5
(
USEPA
AR226­
0473)
pH
(
lg/
L):
2.6
(
MSDS
Merck)

Methanol
solubility:
>
10%
by
weight
(
3M
Study
2001)
Acetone
solubility:
>
10%
by
weight
(
3M
Study
2001)

The
physicocheinical
properties
ofPFOA
and
its
common
derivatives
are
summarized
in
Table
1.
Table
1.
Reported
Physicochemical
Properties
Compound
~
CAS
REG#
MP
BP
VP
SoL­
1120
Log
~*

R­
C(=
O)
Cl
335­
64­
8
13
1
°
C
R­
CO2H
335­
67­
1
55
°
C
189
°
C
lOmmHg
3.4g/
L
R­
CO2­
NF{
4+
3
825­
26­
1
130
°
C(
sub)
Sublirnes
1
x
1OE
­

mmHg
20
g/
L
gels
R­
C(
0)
OMe
376­
27­
2
159
°
C
pH
(
I
g
free
acid/
L
water)
=
1.5
 
2.5
Free
acid
pKa
is
approximately
0.6
Sodium
or
Silver
salts
of
PFOA
decompose
above
250
°
Cto
generate
perfluoroolefins.
Surfactants
traditionally
emulsif~,
ioctanol
and
water
The
environmental
fate
study
results
are
shown
in
Table
2.

Table
2.
PFOA
Environmental
Fate
Data
Product
Cation
%
PFOA
product
Parameter
Resu'ts
.

Comments
Year
Tested
FC­
143
NH4
Soil
Sorption
(
Brill
sandy
loam
soil)
K
=
0.21,
Koc
=
14
Highly
mobile;
3M
Study
1978
FC­
143
NH4
97­
100
30­
day
photolysis
~
xposure
No
evidence
of
degradation
3M
Study
1979
FC­
143
NH4
°

95.2
Direct
and
indirect
photolysis
Minimum
indirect
photolysis
1/
2
life
dt
25
°
C=
>
349
days
No
evidence
of
direct
or
indirect
oss
of
PFOA
was
observed;
3M
Study
2001
FC­
143
NH4
95.2
Hydrolysis
at
pH
1
.5,
5.0,
7.0,
9.0
hydrolytic
1/
2
life
at
25
°
C=
>
97
days
FFOA
loss
was
pH
independent;
3M
Study
2001
FC­
143
NH4
97­
100
og
Kow
­
0.9
Calculated;
3M
Study
1981
FC­
143
NH4
97­
100
.

BCF
­
fathead
minnow
1.8
PFOA
conc.
was
calculated
from
otal
F
conc.
After15­
days
dupuration,
fish
tissue
conc
lropped
from
47
ppm
to
8
ppm
(
wet
weight);
3M
Study
1995
FC­
143
NH4
97­
100
Biodegradation
(
ABS/
LAS
shake
culture)
No
evidence
of
biodegradation
2.5
month
exposure.
Inoculum
mixture
of
municipal
and
3M
industrial
activated
sludge.
3M
Study
1978
:
C..
143
NH4
97­
100
Ready
biodegradability
°
CBOD­
20/
COD
Nil
~
3MStudy
1980
FX­
1
001
H
95­
98
Ready
biodegradability
­
CBOD­
~
0/
COD
Nil
`~
MStudy
1985
Table
2.
PFOA
Environmental
Fate
Data
(
cont.)

Product
Cation
%
PFOA
in
product
Parameter
I
Year
Results
Comments
Tested
FC­
126
NH4
78­
93
Ready
biodegradability
­
CBOD­
20/
COD
0.86
3M
Study
1987
.

FC­
143
NH4
95.2
18­
Day
aerobic
biodegradability
Nith
measured
conc.
No
evidence
of
biodegradation
3M
Study
2001
Information
taken
from
the
Guide
to
the
Safe
Handling
ofFluoropolyiner
Dispersions,
Fluoropolymers
Manufactures
Group,
Society
of
Plastics
Industry,
Washington
DC,
October
2001,
and
the
Preliminary
RiskAssessment
ofthe
Developmental
Toxicity
Associated
with
Exposure
to
Peifluorooctanoic
Acid
and
its
Sa14
US
EPA,
OPPT,
Risk
Assessment
Office,
April
10,
2003
2
Kissa,
ErikFluorinated
Surfactants;
Marcel
Dekker:
New
York,
1994
~
Nakayama,
HaruoBull.
Chem.
Soc.
Jpn.
1967,
40,
1592­
95.

~`
Beilstein
(
1975)
Beilstein
Handbook
4th
Work
Volume
2
Part
2
page
994
3M
data
sheet
for
FC­
26
~
Griffith,
F.
D.
and
Long,
J.
E.
Am.
md.
Hyg.
Assoc.
J.
1980,
41,
576­
83.

~
Lines,
D.
and
Sutcliffe,
H.
I
Fluorine
Chem.
1984,
25(
4),
505­
12.

8
Tiddy,
G.
J.
T.
I.
~
2hem.
Soc.,
Faraday
Trans.
I
1972,
68,
608­
12.

~
Siniister,
EA;
Lee,
EM;
Lu,
JR;
Thomas,
RK;
Ottewill,
RH;
Rennie,
AR;
Penfold,
J.
(
1992).
Adsorption
of
ammoniurn
perfluoroocanoate
and
ammonium
decanoate
at
the­
air­
solution
interface.
J
Chem
Soc,
Faraday
Trans
88(
20):
3033­
41.

10
Calfours,
J;
Stubs,
P.
(
1985)
Solubilization
in
sodium
perfluorooctanoate
micelles:

a
multicomponent
self­
diffusion
study.
Colloid
Interface
Sci
103
:
332­
336.

~
Edwards,
PJB;
Jolley,
KW;
Smith,
MH;
et
al.
(
1997)
Solvent
isotope
effect
on
the
self­
assembly
liquid
crystalline
phase
behavior
in
aqueous
solutions
of
ammonium
pentadecafluorooctanoate.
Langmuir
13(
10):
2665­
2669.

12
Hansch,
C;
Leo,
A;
Eds.
(
1979)
The
fragment
method
of
calculated
partition
coefficients.
In:

Substituent
Constants
for
Correlation
Analysis
and
Chemistry
and
Biology,
Chapter
IV.
JohnWiley
and
Sons,
Inc.
