
Page
1
of
3
UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
MEMORANDUM
Date:
05­
JUL­
2006
Subject:
MGK­
264
Indoor
Handheld
Fogger
Applicator
Scenario:
Comparison
of
Prallethrin
Inhalation
Study
and
Florida
Greenhouse
Study.

DP
Barcode:
D327961
Decision
No.:
334944
PC
Code:
057001
Case
No.:
2430
From:
Steven
Weiss,
Industrial
Hygienist
Reregistration
Branch
3
Health
Effects
Division
(
7509P)

Through:
William
Donovan,
Acting
Branch
Senior
Scientist
Reregistration
Branch
3
Health
Effects
Division
(
7509P)

To:
Cathryn
O'Connell,
Chemical
Review
Manager
Reregistration
Branch
2
Special
Review
and
Reregistration
Division
(
7508P)
Page
2
of
3
MGK­
264
Indoor
Handheld
Fogger
Applicator
Scenario
There
are
no
data
in
ORETF
or
PHED
addressing
the
use
of
a
hand
held
fogger
for
outdoor
applications,
and
no
chemical
specific
data.
Due
to
insufficient
information,
two
different
handheld
fogging
studies
that
were
submitted
for
other
chemicals
were
used
for
inhalation
and
dermal
risk
assessment
for
MGK­
264.

The
exposure
values
estimated
from
the
two
studies
differ
greatly
depending
on
the
type
of
equipment,
duration
of
application,
size
of
fogging
area,
and
air
flow.
One
study
with
the
pyrethroid
prallethrin
(
MRID
45869301)
was
conducted
to
estimate
exposure
from
a
short
(
6
minute)
fogging
application
in
a
small
space.
Another
study
conducted
in
a
Florida
greenhouse
(
MRID
40350501)
may
be
more
appropriate
to
estimate
exposure
for
greenhouse
and
warehouse
applications.
The
estimated
MOE
from
inhalation
exposure
using
the
prallethrin
study
was
12,
while
the
MOE
was
5,700
using
the
Florida
greenhouse
study.
Additional
information
is
needed
to
assess
handheld
fogging
exposure
for
MGK­
264.

Table
1:
Handheld
Fogger
Applicator
Scenario
 
Inhalation
Exposure
Inhalation
Study
Inhalation
UE
Rate
Area
treated
lb
ai
handled
BW
Inhalation
dose
Inhalation
LOAEL
Inhalation
MOE
(
no
respirator)
Inhalation
MOE
(
PF
10
respirator)
mg/
lb
ai
(
lb
ai/
ft3)
ft3
lb
ai
kg
mg/
kg/
day
mg/
kg/
day
Prallethrin
91
0.000006
200,000
1.20
70
1.56
1.86
1.2
12
Nigg
0.19
0.000006
200,000
1.20
70
0.00326
1.86
570
5700
Table
2:
Handheld
Fogger
Applicator
Scenario
 
Dermal
Exposure
Dermal
Study
Inhalation
UE
Rate
Area
treated
lb
ai
handled
BW
Dermal
dose*
Dermal
LOAEL
Dermal
MOE
(
with
double
layers)
mg/
lb
ai
(
lb
ai/
ft3)
ft3
lb
ai
kg
mg/
kg/
day
mg/
kg/
day
Prallethrin
No
data
Nigg
14
0.000006
200,000
1.20
60
0.028
61
2200
*
Dermal
dose
is
based
on
10%
dermal
absorption
Data
Sources
Nigg
Study
Pesticide
Exposure
to
Florida
Greenhouse
Applicators
(
Nigg,
1987):
The
exposure
data
collected
in
this
study
reflect
the
dermal
and
respiratory
exposure
from
the
use
of
hand
held
backpack
foggers
in
a
greenhouse.
The
applicators
in
this
study
were
wearing
chemical
resistant
protective
clothing
(
Tyvek
coveralls)
over
long
sleeve
shirt
and
long
pants,
gloves,
boots,
goggles,
and
a
respirator.
The
workers
in
this
study
were
wearing
chemical
resistant
protective
clothing
and
dermal
patches
Page
3
of
3
were
placed
under
the
chemical
resistant
clothing.
The
Nigg
study
only
provides
three
usable
replicates.

Table
3:
Unit
Exposure
Values
Obtained
From
Pesticide
Exposure
to
Florida
Greenhouse
Applicators
Study
(
Nigg,
1987)
Unit
Dermal
Inhalation
mg
ai/
lb
ai
handled
14
0.19
Prallethrin
Data
The
Prallethrin
data
indicate
that
the
average
concentration
is
6.4
mg/
m3
while
fogging
with
a
2.0%
ai
solution
at
a
spray
volume
of
1
ounce
per
1000
ft3.
This
equates
to
unit
exposure
of
91
mg/
lb
ai
handled.
The
application
was
to
a
481
square
foot
chamber
that
had
an
11
foot
ceiling
and
an
interior
volume
of
5300
ft3.
It
took
6.25
minutes
to
make
the
application.
It
was
assumed
the
MGK­
264
maximum
fogging
rate
is
0.006
lb
ai/
1000ft3
and
the
daily
area
treated
is
200,000
ft3.
