MEMORANDUM
TO:
Najm
Shamim
cc.
11.0248.5000.001.03
Wanda
Jacob
Cletis
Mixon
Pat
Wood
FROM:
Jignasha
Patel/
Traci
Brody/
Ron
Lee,
Versar
Inc.

DATE:
January
23,
2006
SUBJECT:
DDAC
Dietary
Risk
Assessment
Attached
below
is
the
dietary
risk
assessment
for
DDAC.

Please
note
the
following:

 
Product
#
10324­
117
may
be
used
in
potato
storage
areas
where
the
potatoes
are
used
as
food/
feed.
When
treating
potato
storage
areas,
the
label
states
that
all
potatoes
should
be
removed
from
the
premises
before
application,
and
returned
following
air­
drying
of
treatment
solution.
Since
the
product
is
not
to
be
used
directly
on
potatoes,
it
was
assumed
that
exposures
associated
with
this
use
are
smaller
than
the
exposures
associated
with
food
that
comes
into
contact
with
treated
utensils
or
countertops.
 
According
to
the
Chlorine
Dioxide,
Sodium
Chlorite
Memorandum
(
USEPA,
2005),
a
method
for
assessing
treated
mushroom
facilities
has
already
been
designed
by
USEPA.
Versar,
Inc.
did
not
have
more
information
regarding
this
method;
therefore
the
assessment
of
treated
mushroom
facilities
has
not
been
incorporated
into
our
assessment.
It
was
assumed
that
dietary
exposures
from
general
agricultural
premise
use,
poultry
hatcheries,
mushroom
houses
and
hydroponic
uses
are
much
lower
than
the
dietary
exposures
resulting
from
surface
disinfectant
and
sanitizing
uses.

Please
contact
us
if
you
have
any
questions.
DIDECYL
DIMETHYL
AMMONIUM
CHLORIDE
DIETARY
RISK
ASSESSMENT
(
OPPTS
248.5000)

Prepared
for:
Office
of
Pesticide
Programs
Antimicrobial
Division
U.
S.
Environmental
Protection
Agency
1921
Jefferson
Davis
Highway
Arlington,
VA
22202
Prepared
by:
Versar,
Inc.
6850
Versar
Center
Springfield,
VA
22151
EPA
Contract
Number:
68­
W­
01­
036
Work
Assignment
No.
0248.5000.001.03
TAF:
1­
3­
13
Date:
January
20,
2006
Executive
Summary
Didectyl
dimethyl
ammonium
chloride
(
DDAC)
can
be
used
as
a
disinfectant
or
sanitizer
on
counter
tops,
utensils,
appliances,
tables,
refrigerators,
on
animal
premises
and/
or
farms,
and
in
mushroom
premises.
The
use
of
antimicrobial
on
food
or
feed
contact
surfaces,
agricultural
commodities,
in
animal
premises
and
poultry
premises
including
hatcheries
and
application
to
food­
grade
eggs
may
result
in
pesticide
residues
in
human
food.
Residues
from
treated
surfaces,
such
as
utensils,
countertops,
equipment,
and
appliances
can
migrate
to
food
coming
into
contact
with
the
treated
and
rinsed
surfaces
and
can
be
ingested
by
humans.

In
the
absence
of
data
for
residues
of
DDAC
on
treated
food
contact
surfaces,
the
Agency
estimated
residue
levels
that
may
occur
in
food
from
the
application
rates
on
food
contact
surfaces.
Dietary
exposures
from
general
agricultural
premise
use,
poultry
hatcheries,
mushroom
houses
and
hydroponic
uses
are
expected
to
be
much
lower
than
the
dietary
exposures
resulting
from
the
surface
disinfectant
and
sanitizing
uses;
therefore,
these
uses
were
not
assessed.

To
estimate
the
Estimated
Daily
Intake
(
EDI)
to
treated
food
contact
surfaces
and
food
utensils,
an
FDA
(
FDA,
2003)
model
was
used
in
lieu
of
residue
data.
The
maximum
application
rate
for
DDAC
in
food
handling
establishments
from
the
various
labeled
ready­
to­
use
products
is
0.0043
pounds
per
gallon
of
treatment
solution.
The
EDI
calculations
presented
in
this
assessment
assumes
that
food
can
contact
2,000
cm2
or
4,000
cm2
(
50%
and
100%
of
the
FDA
worst
case
scenario)
of
treated
surfaces,
and
that
10%
of
the
pesticide
migrate
to
food,
based
on
the
Agency
Residential
SOPs.
The
use
of
the
10%
transfer
rate,
instead
of
the
use
of
a
100%
transfer
rate
that
is
used
in
the
FDA
Sanitizer
Solution
Guidelines,
requires
the
submission
of
confirmatory
data
to
establish
the
reliability
of
the
use
of
the10%
transfer
rate.
These
daily
estimates
were
conservatively
used
to
assess
both
acute
and
chronic
dietary
risks.
None
of
the
calculated
%
aPad
or
%
cPad
values
exceeded
100%.

The
maximum
application
rate
for
DDAC
for
bottling/
packing
of
food
is
0.0020
lbs
a.
i
per
gallons
of
treatment
solution.
EDI
values
were
calculated
using
an
approach
similar
to
that
used
for
treated
food­
contact
surfaces
and
food
utensils.
Exposure
was
assumed
to
occur
through
the
ingestion
of
three
food
products
that
might
be
packaged
with
treated
material:
milk,
egg
products,
and
beverages
(
alcoholic
and
non­
alcoholic).
None
of
the
calculated
%
aPad
or
%
cPad
values
exceeded
100%.
1.
Dietary
Toxicity
The
acute
or
chronic
Population
Adjusted
Dose
(
aPAD
or
cPAD)
is
presented
in
Table
1.
The
aPAD
and
cPAD
were
both
0.1
mg/
kg/
day
(
Versar,
2006).

Table
1:
DDAC
Dietary
Toxicity
Exposure
Scenario
Dose
Used
in
Risk
Assessment
(
mg/
kg/
day)
Target
MOE/
UF,
Special
FQPA
SF
for
Risk
Assessment
Study
and
Toxicological
Effects
NOAEL
(
developmental)
=
10
mg/
kg/
day
FQPA
SF
=
1
UF
=
100
(
10x
interspecies
extrapolation,
10x
intra­
species
variation)
Prenatal
Developmental
Toxicity
­
Rat
MRID
41886701
LOAEL
=
20
mg/
kg/
day
based
on
increased
incidence
of
skeletal
variations.
Acute
Dietary
(
Females
13­
50)

aPAD
=
0.1
mg/
kg/
day
(
for
Females
age
13­
50)

NOAEL
=
10
mg/
kg/
day
FQPA
SF
=
1
UF
=
100
(
10x
interspecies
extrapolation,
10x
intra­
species
variation
Chronic
Toxicity
Study
­
Dog
MRID
41970401
LOAEL
=
20
mg/
kg/
day
based
on
decreased
total
cholesterol
levels
in
females.
Chronic
Dietary
(
general
population)

cPAD
=
0.1
mg/
kg/
day
a.
cPAD
or
aPAD=
the
RfD/
FQPA
SF
(
acute
RFD
and
FQPA
for
aPAD
and
chronic
RFD
and
FQPA
SF
for
the
cPAD)

2.
Use
Information
Seven
DDAC
products
were
identified
that
have
uses
that
could
lead
to
incidental
ingestion.
These
uses/
products
are
presented
in
Table
2.
The
labels
with
the
maximum­
listed
application
rate
for
each
use
are
presented
in
bold.
Table
2:
Use
Site
Categories
and
Application
Rates
Use
Site
Product
Label
(
Registration
No.)
Method
of
Application
Range
of
Application
Rates
(
lb
a.
i./
gal)
Egg
handling
equipment:
Incubator
and
hatchers
10324­
80
1839­
173
10324­
81
10324­
108
10324­
117
Fogger
0.0223­
0.0563
Hatchery:
hatchery,
settlers,
trays,
racks,
carts,
sexing
tables,
delivery
trucks,
and
other
hard
surfaces
10324­
80
1839­
173
10324­
81
10324­
108
10324­
117
Mop,
cloth,
sponge,
hand
pump
trigger
sprayer,
or
low
pressure
coarse
sprayer
0.0014­
0.0043
Egg
handling
rooms:
hatcheries
10324­
80
1839­
173
10324­
81
10324­
108
10324­
117
10324­
134
Fogger
0.0007­
0.2193
Egg
packing
plants:
food
grade
eggs
1839­
173
10324­
81
10324­
117
Immersion,
low
pressure
coarse
sprayer,
or
swabs
0.0007­
0.0020
Food
handling
establishments:
utensils
and
equipment
1839­
173
10324­
81
10324­
117
Immersion,
low
pressure
coarse
sprayer,
or
swabs
0.0020
Food
handling
establishments:
countertops,
appliances,
and
tables
10324­
81
10324­
108
10324­
117
1839­
173
10324­
80
Mop,
cloth,
sponge,
hand
pump
trigger
sprayer,
or
low
pressure
coarse
sprayer
0.0023­
0.0043
Food
processing
plants:
(
poultry,
meat,
fish,
tobacco
etc.):
hard
surfaces
and
equipment,
including
utensils,
dishes,
silverware,
glasses,
sink
tops,
countertops,
refrigerated
storage,
display
equipment,
storage
shelves,
appliances,
conveyers
(
fruits/
vegetables
or
meat/
poultry)
etc.
10324­
81
10324­
108
10324­
117
10324­
80
1839­
173
10324­
134
Mop,
cloth,
sponge,
hand
pump
trigger
sprayer,
or
low
pressure
coarse
sprayer,
feeding
equipment
0.0020­
0.0043
Use
Site
Product
Label
(
Registration
No.)
Method
of
Application
Range
of
Application
Rates
(
lb
a.
i./
gal)
Bottling/
packaging
sanitizer:
food
contact
surface
sanitizer
(
i.
e.
bottle
sanitizing,
beer
storage
tanks,
and
beverage
dispensing
unit)
1839­
173
10324­
81
10324­
117
Towel,
circulation,
liquid
pour
­
mechanical
or
automated
systems
0.0020
Mushroom
facilities
10324­
80
10324­
81
10324­
108
10324­
117
Mop,
cloth,
sponge,
hand
trigger
sprayer,
or
coarse
spray
device
0.0023­
0.0086
Farm
(
poultry,
swine,
dairy)
premises,
feed
storage
areas,
and
cows
(
uters,
flanks,
and
teats)
1839­
173
10324­
81
10324­
80
1839­
173
10324­
108
10324­
117
Towel,
mop,
cloth,
sponge,
hand
trigger
sprayer,
or
coarse
spray
device
0.0007­
0.0043
3.
Quantitative
Dietary
assessment
3.1
Egg
handling
equipment,
Agricultural
Premise
Use,
and
Poultry
Hatcheries
DDAC
products
may
be
used
on
egg
shells
in
both
poultry
hatcheries
and
food
gradeeggs
Although
it
is
possible
that
some
of
sanitizer/
disinfectant
chemicals
may
penetrate
the
egg
shells,
at
this
time
the
Agency
believes
that
the
amount
of
the
chemical
transferred
into
food
is
likely
to
be
minimal.
Dietary
exposures
from
general
agricultural
premise
use,
poultry
hatcheries,
mushroom
houses
and
hydroponic
uses
are
expected
to
be
much
lower
than
the
dietary
exposures
resulting
from
the
surface
disinfectant
and
sanitizing
uses;
therefore,
these
uses
were
not
assessed.

3.2
Food
Handling
Establishments
and
Food
Processing
Plants
To
calculate
the
EDI
associated
with
use
of
a
DDAC
product
as
a
food
utensil
sanitizer
in
food
handling
establishments,
a
number
of
assumptions
have
been
made
based
on
the
FDA
guidelines
(
FDA,
2003).

1.
When
a
surface
is
treated
with
a
disinfectant,
a
quantity
of
the
disinfectant
remains
on
the
surface
(
Residual
Solution).
The
FDA
recommended
worst­
case
concentration
for
this
quantity
is
1
mg
of
solution
per
square
centimeter
of
treated
surface
area.
In
the
absence
of
any
other
data,
this
value
has
been
used.

2.
The
FDA
suggests
that,
as
a
worst­
case
scenario,
all
food
that
an
individual
consumes
will
come
into
contact
with
4,000
cm2
of
sanitized
non­
porous
food­
contact
surfaces.
This
contact
area
represents
all
the
surface
area
from
silverware,
china,
and
glass
used
by
a
person
who
regularly
eats
three
meals
per
day
at
an
institutional
or
public
facility.

3.
It
is
assumed
that
10%
of
the
active
material
present
on
food
contact
surfaces
will
migrate.

4.
The
body
weights
used
for
this
assessment
are:
adult
man
=
70
kg;
adult
woman
=
60
kg,
and
3­
yr
old
toddler
=
15
kg
(
USEPA,
1997).

For
use
of
a
DDAC
product
as
a
counter
top
disinfectant
in
food
handling
establishments,
the
same
assumptions
as
listed
above
were
used,
and
one
additional
assumption
was
added:

1.
The
amount
of
counter
top
surface
area
that
comes
in
contact
with
food
should
be
much
smaller
than
the
amount
of
food
utensil
area
that
comes
into
contact
with
food.
As
a
conservative
estimate,
it
is
assumed
that
50%
of
the
FDA
value,
or
2,000
cm2
of
treated
counter
top
surface
area,
comes
into
contact
with
an
individual's
food
per
day.

The
above
assumptions
and
the
following
equations
were
used
to
calculate
EDI
and
Dietary
Daily
Dose
(
DDD):

EDI
(
mg/
p/
day)
=
AR
x
RS
x
SA
x
F
x
10­
6
(
1)
DDD
(
mg/
kg/
day)
=
AR
x
RS
x
SA
x
F
x
10­
6/
BW
(
2)

Where:
AR
=
Application
rate
(
ppm)
RS
=
Residual
solution
(
mg/
cm2)
SA
=
Surface
area
of
the
treated
surface
which
comes
into
contact
with
food
(
cm2)
F
=
Fraction
of
the
pesticide
transferred
or
migrated
to
food
(
unitless)
BW
=
Body
weight
(
kg)

The
input
parameters
listed
in
Table
4
and
equations
1
and
2
were
used
to
calculate
the
output
parameters
listed
in
Table
5.

Table
4:
Input
Parameters
for
Food
Handling
Establishments
and
Food
Processing
Plants
Hard
Surface
Sanitizer
Parameter
Value
Rationale
Food
Utensil
Countertop
Residual
Solution
on
Surface
1
mg/
cm2
FDA
worst­
case
assumption
Area
of
Treated
Surface
4,000
cm2
2,000
cm2
100%
and
50%
of
FDA
worstcase
assumption
for
food
utensils
DDAC
concentration
in
diluted
Solutiona
0.0020
lb
a.
i./
gal
or
240
ppm
0.0043
lb
a.
i./
gal
or
515
ppm
Diluted
Solution
concentration,
based
on
maximum
concentration.

Fraction
Transferred
10%
EPA
Assumption
Body
Weight
(
kg)
Adult
man
=
Adult
woman
=
Child
=
70
60
15
EPA,
1997
a.
Maximum
application
rates
for
food
utensils
were
from
product
labels
1839­
173,
10324­
81,
and
10324­
117
for
Utensils
and
product
label
10324­
80
for
counter­
tops.
Table
5:
Calculated
EDIs,
aPAD,
and
cPAD
for
Utensils
and
Countertops
Utensils
Countertops
Aggregate
Exposure
Group
EDI
(
mg/
p/
d)
DDD
(
mg/
kg/
d)
%
PADa
EDI
(
mg/
p/
d)
DDD
(
mg/
kg/
d)
%
PADa
EDI
(
mg/
p/
d)
DDD
(
mg/
kg/
d)
%
PADa
(
mg/
kg/
d)
Adult
males
0.0959
0.00137
1.37
0.103
0.00147
1.47
0.199
0.00284
2.84
Adult
females
0.0959
0.00160
1.60
0.103
0.00172
1.72
0.199
0.00332
3.32
Children
0.0959
0.00639
6.39
0.103
0.00687
6.87
0.199
0.0133
13.3
a.
%
PAD
=
exposure
(
DDD)
/(
aPAD
or
cPAD)
x
100.
The
acute
and
chronic
population
average
dose
is
the
same;
therefore
the
%
PADs
are
the
same.

For
DDAC
treatments
of
food
processing
plants,
the
application
rates
are
similar
to
food
handling
establishments
presented
above,
and
hence
the
exposure,
EDIs,
DDDs,
and
%
aPAD
and
cPADs
are
also
similar.

3.4.
Food
Bottling/
Packaging
DDAC
may
also
be
used
as
a
sanitizer
or
disinfectant
in
processing
equipments,
utensils
in
dairies,
breweries,
canning
operations,
meat
and
vegetable
processing
plants.
In
assessing
this
use,
the
following
assumptions
were
made,
based
on
USEPA
(
2005):

1.
The
DDAC
concentration
in
the
treatment
solution
is
0.0020
lb
a.
i./
gal,
or
240
ppm
(
0.00024
wt/
wt)

2.
When
a
surface
is
treated
with
a
disinfectant,
a
quantity
of
the
disinfectant
remains
on
the
surface
(
Residual
Solution).
The
FDA
recommended
worst­
case
concentration
for
this
quantity
is
1
mg
of
solution
per
square
centimeter
of
treated
surface
area.
In
the
absence
of
any
other
data,
this
value
has
been
used.

3.
For
the
fraction
of
pesticide
that
migrates
from
the
residue
to
the
food
(
F
in
equations
3
and
4),
a
transfer
rate
of
100%
was
used
instead
of
10%
because
the
food
is
in
contact
with
the
treated
surfaces
for
potentially
very
long
periods
of
time.

4.
For
a
given
person,
the
grams
of
food
per
surface
area
of
container
were
as
follows
(
g/
cm2):
a.
Milk
(
dairy):
6.6
b.
Egg/
mayonnaise:
64.0
c.
Beer,
beverages:
150
5.
The
daily
intake
rates
for
an
adult
(
g/
person/
day)
were
as
follows:

a.
Beverages,
alcoholic/
beer:
182
b.
Beverages,
non­
alcoholic:
240
c.
Egg
products:
9.0
d.
Milk:
124
6.
A
child
will
consume
a
smaller
quantity
of
calories
in
a
given
day.
To
account
for
differences
between
intake
values
among
children
and
adults
a
calorie
intake
modification
factor
of
0.64
was
applied
to
the
EDI
for
a
child.
Recommended
energy
allowances
measured
in
kilocalories
per
body
weight
for
different
age
groups
and
genders
were
taken
from
the
National
Research
Counsil's
Recommended
Energy
Allowances.
The
values
are
based
on
the
resting
energy
expenditure
and
the
energy
required
for
light
to
moderate
levels
of
activity,
as
determined
by
the
World
Health
Organization
(
USAID,
2005).
The
calculation
of
the
factor
is
presented
in
Table
6
below.

The
above
assumptions
and
the
following
equations
were
used
to
calculate
EDI
and
Dietary
Daily
Dose
(
DDD):

EDI
(
mg/
p/
day)
=
AR
x
RS
x
DIR
x
MSA­
1
x
F
x
10­
6
x
CMF
(
3)

DDD
(
mg/
kg/
day)
=
AR
x
RS
x
DIR
x
MSA­
1
x
F
x
10­
6
x
CMF/
BW
(
4)

Where:
AR
=
Application
rate
(
ppm)
RS
=
Residual
solution
(
mg/
cm2)
MSA
=
Mass­
surface
area
ratio
(
the
treated
surface
that
comes
into
contact
with
food)
(
g/
cm2)
DIR
=
Daily
intake
rate
of
food
in
a
given
day
(
g/
p/
day)
F
=
Fraction
of
the
pesticide
transferred
or
migrated
to
food
(
unitless)
BW
=
Body
weight
(
kg)
CMF
=
Calorie
intake
modification
factor
(
100%
adults;
64.4%
Children)

Assumptions
1­
4,
inputs
from
Table
6
and
7,
and
equations
3
and
4
were
used
to
calculate
the
dietary
rates
and
doses
presented
in
Table
8.

Table
6:
Toddler
(
3­
yr
old)
and
Adult
Calorie
Intake
Comparison
Group
(
Age)
Body
Weight
(
kg)
Kilocalories
per
kga
Kilocaloriesb
Child
(
1­
3)
15.0
102
1,530
Female
(
25­
50)
60.0
36.0
2,160
Male
(
25­
50)
70.0
37.0
2,590
Output
Child
Modification
Factor
(
CMF)
c
0.644
a.
USAID,
2005
b.
Kilocalories
=
Kcal/
Kg
x
BW
c.
CMF
=
Kcal­
child
÷
[(
Kcal­
female
+
Kcal­
male)/
2]
Table
7:
Input
Parameters
for
Food
Bottling/
Packaging
Hard
Surface
Sanitizer
Parameter
Input
Rational
Milk
6.6
Egg/
Mayonnaise
64
Food
mass/
surface
(
g/
cm2)
Beer,
beverages
150
USEPA,
2005
Milk
124
Egg
products
9
Beer,
beverages
182
Intake
rates
(
g/
p/
d)
Beverages/
nonalcoholic
240
USEPA,
2005
Fraction
Transferred
100%
FDA
worst
case
assumption
Residual
Solution
on
Surface
1
mg/
cm2
FDA
worst
case
Assumption
Quantity
DDAC
0.0020
lb
ai
or
240
ppm
Diluted
solution
concentration,
based
on
maximum
concentration.
Body
Weight
(
kg)
Adult
man
=
Adult
woman
=
Child
=
70
60
15
USEPA,
1997
a.
Maximum
application
rates
for
food
utensils
were
from
product
labels
1839­
173,
10324­
81,
and
10324­
117.

Table
8:
Calculated
EDIs,
aPAD,
and
cPAD
for
Representative
Dairy
and
Beverage
Consumption
Food
Type
Exposure
Group
EDI
(
mg/
p/
d)
DDD
(
mg/
kg/
d)
%
PAD
Adult
Male
6.44x10­
5
0.0644
Adult
Female
0.00451
7.52x10­
5
0.0752
Milk
Childa
0.00290
1.94x10­
4
0.194
Adult
Male
1.16x10­
10
1.16x10­
7
Adult
Female
8.10x10­
9
1.35x10­
10
1.35x10­
7
Egg
product
Child
a
5.22x10­
9
3.48x10­
10
3.48x10­
7
Adult
Male
3.29x10­
4
0.329
Adult
Female
0.0230
3.84x10­
4
0.384
Beverages,
non­
alcoholic
Childa
0.0148
9.90x10­
4
0.990
Adult
Male
4.16x10­
6
0.00416
Beverages,
alcoholic,
beer
Adult
Female
2.91x10­
4
4.85x10­
6
0.00485
a.
Child
EDI
values
are
multiplied
by
a
modification
factor
of
0.644
4.0
References
FDA.
2003.
"
Sanitizing
Solutions:
Chemistry
Guidelines
for
Food
Additive
Petitions."
http://
www.
cfsan.
fda.
gov/~
dms/
opa­
cg3a.
html.
Last
accessed
June
9,
2003.

USAID.
2005.
"
ANNEX
III:
Recommended
Energy
Allowance
Tables."
November
2005.
http://
www.
usaid.
gov/
our_
work/
humanitarian_
assistance/
ffp/
crg/
annex­
3.
htm.
Last
viewed
January
23,
2006.

USEPA.
1997.
Exposure
Factors
Handbook.
Volume
I­
II.
Office
of
Research
and
Development.
Washington,
D.
C.
EPA/
600/
P­
95/
002Fa.
August
1997.

USEPA.
2005.
Dietary
Assessment
of
Chlorine
Dioxide,
Sodium
Chlorite
From
Their
Use
As
Indirect
Food
Contact
Sanitizers/
Disinfectants
(
Hard
Surface
Sanitizers).
Memorandum
from
Najm
Shamim,
USEPA
to
Melba
Morrow
and
Jennifer
Slotnick,
USEPA.
Dates
August
15,
2005.

Versar.
2006.
DDAC
Occupational
and
Residential
Exposure
Assessment.
Memorandum
from
Adria
Diaz/
Karie
Riley/
Kelly
McAloon,
Versar,
Inc.,
to
Laura
Bailey,
USEPA
dated
January
20,
2006.
