1
of
5
DRAFT
FIFRA
SCIENTIFIC
ADVISORY
PANEL
(
SAP)
OPEN
MEETING
AUGUST
24
­
25,
2004
FIFRA
SAP
WEB
SITE
http://
www.
epa.
gov/
scipoly/
sap/
OPP
Docket
Telephone:
(
703)
305­
5805
Docket
Number:
OPP­
2004­
0240
TUESDAY,
AUGUST
24,
2004
Holiday
Inn
­
National
Airport
2650
Jefferson
Davis
Highway
Arlington,
VA
22202
Telephone:
(
703)
684­
7200
FUMIGANT
BYSTANDER
EXPOSURE
MODEL
REVIEW:
PROBABILISTIC
EXPOSURE
AND
RISK
MODEL
FOR
FUMIGANTS
(
PERFUM)
USING
IODOMETHANE
AS
A
CASE
STUDY

8:
30
AM
Introduction
and
Identification
of
Panel
Members
 
Stephen
M.
Roberts,
Ph.
D.
(
FIFRA
SAP
Chair)


8:
45
AM
Administrative
Procedures
by
Designated
Federal
Official
­
Ms.
Myrta
Christian

8:
50
AM
Welcome
­
Mr.
Joseph
J.
Merenda,
Jr.
(
Director,
Office
of
Science
Coordination
and
Policy.
EPA)


8:
55
AM
Opening
Remarks
­
Mr.
Jim
Jones
(
Director,
Office
of
Pesticide
Programs,
EPA)


9:
00
AM
Introduction,
Goals
and
Objectives
 
Mr.
Jeffrey
Dawson
(
Office
of
Pesticide
Programs,
EPA)


9:
15
AM
Probabilistic
Exposure
and
Risk
Model
for
Fumigants
(
PERFUM)
­
Dr.
Richard
Reiss
on
behalf
of
the
Arvesta
Corporation

10:
00
AM
BREAK

10:
15
AM
Probabilistic
Exposure
and
Risk
Model
for
Fumigants
(
PERFUM)
­
Dr.
Richard
Reiss
on
behalf
of
the
Arvesta
Corporation

11:
30
AM
LUNCH

12:
30
PM
Public
Comments

1:
30
PM
Questions
to
the
Panel
Critical
Element
1:
Documentation
Question
1:
The
background
information
presented
to
the
SAP
panel
by
the
PERFUM
developers
provides
both
user
guidance
and
a
technical
overview
of
the
system.
Please
2
of
5
comment
on
the
detail
and
clarity
of
this
document.
Are
the
descriptions
of
the
specific
model
components
scientifically
sound?
Do
the
algorithms
in
the
annotated
code
perform
the
functions
as
defined
in
this
document?
Please
discuss
any
difficulties
encountered
with
respect
to
loading
the
software
and
evaluating
the
system
including
the
presented
case
study?

Critical
Element
2:
System
Design/
Inputs
Question
2:
In
Section
2.3:
Development
of
the
PERFUM
Modeling
System
of
the
background
document,
a
series
of
detailed
individual
processes
and
components
included
in
PERFUM
are
presented.
The
key
processes
include
(
1)
incorporation
of
ISCST3
into
PERFUM,
(
2)
probabilistic
treatment
of
flux
rates;
and
(
3)
development
of
a
receptor
grid.
Please
comment
on
these
proposed
processes,
the
nature
of
the
components
included
in
PERFUM
and
the
data
needed
to
generate
an
analysis
using
PERFUM?
Are
there
any
other
potential
critical
sources
of
data
or
methodologies
that
should
be
considered?


3:
00
PM
BREAK

3:
15
PM
Questions
to
the
Panel
(
continued)

Question
3:
The
determination
of
appropriate
flux/
emission
rates
is
critical
to
the
proper
use
of
the
PERFUM
model
as
these
values
define
the
source
of
fumigants
in
the
air
that
can
lead
to
exposures.
Upon
its
review
of
how
flux
rates
can
be
calculated,
the
Agency
has
identified
a
number
of
questions
it
would
like
the
panel
to
consider.
In
PERFUM,
flux
rates
were
treated
as
a
probabilistic
variable
with
an
uncertainty
developed
from
the
statistical
bounds
of
the
flux
calculation.
For
each
measurement
period
a
standard
error
is
generated
that
reflects
the
measurement
uncertainty
of
the
flux
rate.
PERFUM
then
perturbs
the
concentration
estimates
within
each
period
by
the
standard
error
using
Monte
Carlo
methods
to
simulate
the
uncertainty
in
the
flux
estimates.
What,
if
any,
refinements
are
needed
for
this
process
including
the
manner
in
which
flux
values
were
calculated
for
each
monitoring
period
to
generate
the
standard
error
estimates?
How
appropriate
is
it
to
use
a
flux/
emission
factor
from
a
single
monitoring
study
(
or
small
number
of
studies)
and
apply
it
to
different
situations
such
as
for
the
same
crop
in
a
different
region
of
the
country?
Please
comment
on
PERFUM's
capability
to
adequately
consider
multiple,
linked
application
events
as
well
as
single
source
scenarios?
Does
PERFUM
appropriately
address
situations
where
data
are
missing?
In
the
backcalculation
approach
used
for
estimating
emission
rates,
the
regression
of
measured
versus
modeled
values
can
be
forced
through
the
origin
or
not.
Which
approach
does
the
panel
prefer
and
what
are
the
implications
of
each
approach?


4:
30
PM
ADJOURNMENT
3
of
5
DRAFT
FIFRA
SCIENTIFIC
ADVISORY
PANEL
(
SAP)
OPEN
MEETING
AUGUST
24
­
25,
2004
FIFRA
SAP
WEB
SITE
http://
www.
epa.
gov/
scipoly/
sap/
OPP
Docket
Telephone:
(
703)
305­
5805
Docket
Number:
OPP­
2004­
0240
WEDNESDAY,
AUGUST
25,
2004
Holiday
Inn
­
National
Airport
2650
Jefferson
Davis
Highway
Arlington,
VA
22202
Telephone:
(
703)
684­
7200
FUMIGANT
BYSTANDER
EXPOSURE
MODEL
REVIEW:
PROBABILISTIC
EXPOSURE
AND
RISK
MODEL
FOR
FUMIGANTS
(
PERFUM)
USING
IODOMETHANE
AS
A
CASE
STUDY

8:
30
AM
Introduction
and
Identification
of
Panel
Members
 
Stephen
M.
Roberts,
Ph.
D.
(
FIFRA
SAP
Chair)


8:
35
AM
Administrative
procedures
by
Designated
Federal
Official
­
Ms.
Myrta
Christian

8:
40
AM
Follow­
up
from
Previous
Day's
Discussion
 
Mr.
Jeffrey
Dawson
(
Office
of
Pesticide
Programs,
EPA)


9:
00
AM
Questions
to
the
Panel
(
continued)

Question
4:
The
integration
of
actual
time­
base
meteorological
data
into
ISCST3
is
one
of
the
key
components
that
separates
the
PERFUM
methodology
from
that
being
employed
by
the
Agency
in
its
current
assessment.
There
are
several
potential
sources
of
these
data
including
the
National
Weather
Service,
Federal
Aviation
Administration,
California
Irrigation
Management
Information
System
(
CIMIS),
and
the
Florida
Automated
Weather
Network
(
FAWN).
The
Agency
is
also
aware
that
there
are
several
approaches
that
can
be
used
to
process
meteorological
data
and
acknowledges
that
PERFUM
used
PCRAMMET
which
is
a
standard
Agency
tool
for
this
purpose
as
well
as
other
techniques
in
some
cases
(
e.
g.,
for
the
FAWN
&
CIMIS
data).
Various
datasets
from
both
California
and
Florida
were
used
as
the
basis
for
the
PERFUM
case
study.
Please
comment
on
the
methods
used
to
select
monitoring
station
locations?
What
criteria
should
be
used
to
identify
meteorological
regions
for
analysis
and
how
should
specific
monitoring
data
be
selected
from
within
each
region?
Please
comment
on
the
manner
that
data
from
the
selected
various
stations
were
processed?
Data
quality
and
uncertainty
associated
with
these
data
vary
with
the
source.
Does
the
panel
agree
with
the
approaches
used
to
characterize
these
factors?
Anemometer
sampling
height
has
been
identified
as
a
concern
by
the
Agency
in
preparation
for
this
meeting.
What
are
the
potential
impacts
of
using
data
collected
with
different
anemometer
heights
in
an
analysis
4
of
5
of
this
nature?
Does
PERFUM
treat
stability
class
inputs
appropriately?
Does
PERFUM
appropriately
calculate
bounding
air
concentration
estimates
by
concurrently
using
upperbound
meteorological
and
emission/
flux
inputs?


10:
30
AM
BREAK

10:
45
AM
Questions
to
the
Panel
(
continued)

Question
5:
The
Agency
model,
ISCST3
is
the
basis
for
the
PERFUM
approach.
This
model
has
been
peer
reviewed
and
is
commonly
used
for
regulatory
purposes
by
the
Agency.
PERFUM
also
uses
other
Agency
systems
such
as
PCRAMMET.
Please
recommend
any
parameters
that
should
be
altered
to
optimize
the
manner
that
they
are
used
in
PERFUM?
Does
the
panel
agree
with
the
manner
in
which
the
receptor
grid
was
developed,
and
if
not,
please
provide
suggestions
for
improving
this
approach?
ISCST3,
as
integrated
into
PERFUM,
was
run
assuming
rural,
flat
terrain
which
would
be
typical
of
treated
farm
fields
but
might
not
be
typical
of
surrounding
residential
areas.
Does
the
panel
concur
with
this
approach?
What
are
the
implications
of
such
an
approach?
What
improvements
can
be
made
to
this
approach?
ISCST3,
as
integrated
into
PERFUM,
was
run
in
regulatory
mode
which
includes
the
use
of
the
"
calms"
processing
routine.
Does
the
panel
concur
with
this
approach?
If
not,
please
suggest
a
suitable
alternative?



12:
00
AM
LUNCH

1:
00
PM
Questions
to
the
Panel
(
continued)

Critical
Element
3:
Results
Question
6:
Soil
fumigants
can
be
used
in
different
regions
of
country
under
different
conditions
and
they
can
be
applied
with
a
variety
of
equipment.
Please
comment
on
whether
the
methodologies
in
PERFUM
can
be
applied
generically
in
order
to
assess
a
wide
variety
of
fumigant
uses?
What
considerations
with
regard
to
data
needs
and
model
inputs
should
be
considered
for
such
an
effort?

Question
7:
Please
comment
on
whether
PERFUM
adequately
identifies
and
quantifies
airborne
concentrations
of
soil
fumigants
that
have
migrated
from
treated
fields
to
sensitive
receptors?
The
Agency
is
particularly
concerned
about
air
concentrations
in
the
upper
ends
of
the
distribution.
Are
these
results
presented
in
a
clear
and
concise
manner
that
would
allow
for
appropriate
characterization
of
exposures
that
could
occur
at
such
levels?
The
PERFUM
model
calculates
the
concentration
distributions
both
in
all
directions
and
for
only
the
maximum
concentration
direction.
Can
the
panel
comment
on
how
accurately
the
model
approximates
both
of
these
distributions?



2:
30
PM
BREAK

2:
45
PM
Questions
to
the
Panel
(
continued)
5
of
5
Question
8:
A
sensitivity/
uncertainty
analysis
has
been
conducted
and
is
described
in
the
PERFUM
background
document.
What
types,
if
any,
of
additional
contribution/
sensitivity
analyses
are
recommended
by
the
panel
to
be
the
most
useful
in
making
scientifically
sound,
regulatory
decisions?
What
should
be
routinely
reported
as
part
of
a
PERFUM
assessment
with
respect
to
inputs
and
outputs?
Are
there
certain
tables
and
graphs
that
should
be
reported?
What
types
of
further
evaluation
steps
does
the
panel
recommend
for
PERFUM?


3:
30
PM
ADJOURNMENT
Please
be
advised
that
agenda
times
are
approximate.
For
further
information,
please
contact
the
Designated
Federal
Official
for
this
meeting,
Ms.
Myrta
Christian,
via
telephone:
(
202)
564­
8450;
fax:
(
202)
564­
8382;
or
email:
christian.
myrta@
epa.
gov
