UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
April
13,
2006
OFFICE
OF
PREVENTION
PESTICIDES
AND
TOXIC
SUBSTANCES
Memorandum
SUBJECT:
Biological
and
Economic
Analysis
of
Dichlorvos
for
Pet
Collars
FROM:
Don
Atwood,
Entomologist
Biological
Analysis
Branch
Biological
and
Economic
Analysis
Division
(
7503C)

THRU:
Arnet
Jones,
Chief
Biological
Analysis
Branch
Tim
Kiely,
Acting
Chief
Economic
Analysis
Branch
Biological
and
Economic
Analysis
Division
(
7503C)

TO:
Dayton
Eckerson/
Eric
Olson,
Chemical
Review
Manager
Reregistration
Branch
1
Special
Review
and
Reregistration
Division
(
7508C)

PRP
REVIEW
DATE:
March
31,
2006
SUMMARY
Flea/
Tick
collars
only
represent
20%
of
the
total
pet
pest
control
market.
Recent
trends,
1997­
2001,
indicate
market
movement
away
from
pest
collars
towards
rub­
in/
spot­
on
products
and
veterinarian
medications.
Numerous
alternative
active
ingredients
are
currently
marketed
as
pest
collars
for
flea
and
tick
control.
Taking
into
account
the
availability
of
alternative
insecticides,
both
pest
collar
and
other,
and
the
changing
trend
in
residential
flea
and
tick
control,
BEAD
concludes
that
their
would
be
no
biological
impact
from
the
absence
of
dichlorvos
in
the
pest
collar
market.
As
dichlorvos
is
not
currently
marketed
as
a
flea/
tick
collar
product,
no
economic
analysis
was
conducted
in
the
course
of
this
assessment.
2
I.
SCOPE
AND
LIMITATIONS
OF
ASSESSMENT
The
scope
of
this
assessment
is
at
the
national
level.
The
scope
of
this
analysis
includes
an
examination
of
impacts
associated
with
no
longer
allowing
the
use
of
dichlorvos
in
flea
and
tick
colars.
This
mitigation
scenario
reflects
the
health
risks
as
identified
by
the
Health
Effects
Division
of
the
Office
of
Pesticide
Programs.

There
are
limits
to
this
assessment.
The
primary
limit
is
the
lack
of
data
associated
with
dichlorvos
use
in
flea
and
tick
collars.
Although
registered
for
this
use,
no
products
containing
dichlorvos
are
currently
marketed.
The
lack
of
usage
and
economic
data
makes
the
benefit
analysis
rely
chiefly
on
alternative
insecticides.

BEAD
assessment
is
based
on
the
best
professional
judgement
of
BEAD
analysts
when
estimates
are
not
available
from
other
sources.
BEAD
has
relied
largely
on
state
pesticide
recommendations
and
proprietary
usage
data.
In
the
absence
of
efficacy
data,
is
assumed
that
the
recommended
alternative
insecticides
are
efficacious
against
the
target
pests.

II.
INSECTICIDE
USAGE
FOR
FLEA
/
TICK
CONTROL
ON
DOGS
AND
CATS
Usage
data
for
dichlorvos
to
kill
fleas
and
ticks
on
dogs
and
cats
is
not
available.
However,
usage
data
is
available
for
other
currently
marketed
pet
products.
Insecticidal
flea/
tick
treatments
for
pets
is
available
as
collars,
on­
animal
sprays,
shampoos,
dips,
powder,
liquid
rubin
spot­
on,
and
veterinarian
medication.
Use
of
insecticides
is
greatest
on
dogs
and
for
flea
control,
each
accounting
for
approximately
70%
of
revenues.
Flea/
tick
collars
,
veterinary
medication,
and
shampoo
all
have
similar
usage
patterns
by
dog
owners,
approximately
20%
of
product
use.
Usage
pattern
for
cat
owners
is
similar
to
that
with
dogs
but
with
liquid
rub­
in/
spot­
on
replacing
shampoos.
Pet
collars
for
flea
and
tick
control
amounts
to
less
than
10%
of
all
total
flea/
tick
control
revenues.
However,
trends
indicate
a
greater
number
of
pet
owners,
both
dog
and
cat,
switching
away
from
collars.
In
addition,
revenues
generated
by
liquid
rub­
in/
spot­
on
products
increased
by
more
than
350%
between
1997
and
2000.

III.
INSECTICIDES
AVAILABLE
FOR
FLEA/
TICK
CONTROL
ON
PETS
Flea
control
is
best
achieved
with
a
simultaneous,
coordinated
effort
involving
strict
sanitation,
pet
treatment
and
premise
treatment
(
both
indoors
&
outdoors).

A.
INSECTICIDE
ALTERNATIVES
1.
Collars
­
There
is
a
great
variety
of
flea/
tick
collars
available
to
pet
owners.
Control
can
extend
from
4­
12
months
depending
on
the
active
ingredient.
Collars
represent
less
than
10%
of
total
revenues
for
flea/
tick
control.
The
3
leading
active
ingredients
include
propoxur,
carbaryl,
and
naled.
Other
active
ingredients
in
flea/
tick
collars
include;
tetachorvinphos
+
methoprene,
d­
limonene
+
linalool,
rotenone,
allethrin,
methoprene,
permethrin
(
dog
use
only),
and
amitraz
(
dog
use
only).

2.
Sprays
­
Sprays
are
one
of
the
most
common
flea/
tick
control
products
available.
The
most
common
active
ingredient
in
use
for
sprays
is
pyrethrum.
Numerous
collars
may
also
include
an
insect
growth
regulator
(
IGR)
such
as
methoprene
in
combination
with
pyrethrum
to
provide
adult
flea
and
tick
control
as
well
as
larval
flea
control.

3.
Shampoos
­
As
with
sprays,
most
shampoos
are
based
on
pyrethrum
as
the
active
ingredient.
There
has
been
a
move
away
from
shampoo
use
for
flea/
tick
control
for
both
dogs
and
cats
(
though
more
pronounced
for
cats).
A
few
natural
products
are
also
marketed
as
shampoos
containing
dlimonen
a
citrus
extract,
for
flea/
tick
control.

4.
Dips
­
Dips
are
no
longer
widely
used
by
pest
owners
even
though
they
are
highly
effective.
This
is
largely
due
to
the
fact
that
they
are
hard
to
use
and
are
messy.
Most
dips
provide
immediate
control
with
residual
activity
of
up
to
7
days.
The
leading
active
ingredients
for
use
in
dips
are
permethrin
and
pyrethrum.

5.
Powders
­
As
with
dips,
powders
for
flea/
tick
control
only
have
limited
use
as
the
difficult
to
apply
and
are
unattractive
on
the
pet's
coat.
Active
ingredients
most
commonly
used
in
powders
are
carbaryl
and
pyrethrum.

6.
Rub­
in/
Spot­
on
­
Use
of
rub­
in/
spot­
ons
has
increased
by
over
350%
in
the
last
3
years.
This
market
has
grown
specifically
at
the
expense
of
the
more
traditional
treatments.
Rub­
in/
Spot­
ons
account
for
the
second
largest
sales
revenue
for
the
flea
and
tick
market,
less
than
15%.
The
active
ingredients
most
commonly
used
in
rub­
in/
spot­
on
treatments
are
fipronil
and
imidacloprid.

7.
Veterinarian
medications
­
Since
1997,
veterinarian
medications
to
control
fleas
and
ticks
has
increased
by
approximately
7%
annually.
Veterinarian
medications
account
for
over
60%
of
sales
revenue.
Active
ingredients
commonly
found
in
veterinarian
medications
include
lufenuron,
selamectin,
and
nitenpyram.

IV.
ALTERNATIVE
NONCHEMICAL
CONTROL
OF
FLEAS
AND
TICKS
No
alternative
nonchemical
controls
are
available
that
would
provide
acceptable
control
of
4
fleas
and
ticks.
Control
must
include
pet
treatment,
premise
treatment,
and
sanitation.
Insecticides
are
an
integral
part
residential
flea/
tick
control
program.

V.
BIOLOGICAL
IMPORTANCE
OF
DICHLORVOS
FOR
FLEA/
TICK
CONTROL
No
biological
impact
would
be
expected
in
the
absence
of
dichlorvos
for
use
in
flea/
tick
collars
on
pets.
Flea
collars
only
represent
20%
of
total
pet
insecticide
use
and
only
account
for
10%
of
total
pet
insecticide
revenues.
The
recent
trend
for
pet
pest
control
products
has
been
away
from
collars
and
towards
rub­
in/
spot­
on
products
and
veterinarian
medications.
Due
to
the
large
number
of
active
ingredients
currently
available
in
flea/
tick
collars
and
the
move
toward
other
pet
treatment
methods,
the
absence
of
dichlorvos
from
the
flea/
tick
collar
market
will
have
no
biological
impact.

VI.
ECONOMIC
IMPORTANCE
OF
DICHLORVOS
FOR
FLEA/
TICK
CONTROL
As
dichlorvos
currently
has
no
market
for
pet
collars,
no
economic
impacts
are
expected.

VII.
REFERENCES
1.
EPA
Proprietary
Data.
2001.

2.
Pet
Products
to
Control
Pests.
2001.
FDA
http://
www.
fda.
gov/
fdac/
features/
2001/
petchart.
html
3.
Veterinary­
Prescribed
Products
.
Ohio
State
University.
Extension
Bulletin
586
http://
ohioline.
osu.
edu/
b586/
b586_
5.
html
4.
Fighting
Fleas
and
Ticks.
1996.
FDA.
http://
www.
fda.
gov/
fdac/
features/
696_
flea.
html
