Page
1
of
7
United
States
Prevention,
Pesticides
EPA
738­
R­
05­
005
Environmental
Protection
and
Toxic
Substances
July
13,
2006
Agency
(
7508C)

Report
of
the
Food
Quality
Protection
Act
(
FQPA)
Tolerance
Reassessment
and
Risk
Management
Decision
(
TRED)
for
Sodium
Cyanide
Page
2
of
7
Report
of
the
Food
Quality
Protection
Act
(
FQPA)
Tolerance
Reassessment
and
Risk
Management
Decision
(
TRED)
for
Sodium
Cyanide
Approved
By:

___________________
Debra
Edwards,
Ph.
D.
Director,
Special
Review
and
Reregistration
Division
_________________________
Date
Abstract
Page
3
of
7
This
document
presents
EPA's
decision
regarding
the
tolerance
reassessment
of
the
registered
uses
of
sodium
cyanide.
The
Agency
has
determined
that
there
is
a
reasonable
certainty
that
no
harm
to
any
population
subgroup
will
result
from
exposure
to
sodium
cyanide.
Therefore,
the
one
tolerance
established
for
residues
of
the
insecticide
hydrogen
cyanide
as
a
result
of
application
of
sodium
cyanide
is
now
considered
reassessed
as
safe
under
section
408(
q)
of
the
Federal
Food,
Drug
and
Cosmetic
Act
(
FFDCA),
as
amended
by
the
Food
Quality
Protection
Act
(
FQPA).
EPA
issued
a
Reregistration
Eligibility
Decision
(
RED)
for
Sodium
Cyanide
in
September
1994.

As
an
insecticide,
sodium
cyanide
is
used
in
California
as
a
source
of
hydrocyanic
gas
for
quarantine
fumigation
of
surface
pests
on
citrus
bound
for
Arizona.
Sodium
cyanide
is
also
used
in
mining,
metal
finishing
and
organic
chemical
industries.
For
this
reason,
the
Agency
also
evaluated
potential
exposure
and
risk
from
cyanide
in
drinking
water
sources
in
Arizona.

This
TRED
addresses
the
FQPA
requirement
for
reassessment
of
the
tolerance
for
hydrogen
cyanide
and
provides
an
assessment
of
worker
exposure
associated
with
the
use
of
sodium
cyanide
as
a
source
of
hydrocyanic
gas
for
fumigation
of
surface
pests
on
citrus.
Although
a
TRED
typically
does
not
include
an
occupational
assessment,
this
document
addresses
occupational
exposures
that
were
not
addressed
in
the
September
1994
RED.

The
Agency
is
issuing
this
TRED
document
for
sodium
cyanide
as
announced
in
a
Notice
of
Availability
published
in
the
Federal
Register.
The
Agency
is
providing
a
60­
day
period
for
stakeholders
to
comment
on
the
risk
assessment
and
respond
to
this
risk
management
decision.
If
substantive
information
is
received
during
the
comment
period
that
indicates
a
need
to
reconsider
the
decisions
presented
in
this
document,
EPA
may
modify
these
decisions
as
appropriate
through
an
amendment.

I.
Introduction
This
is
the
Environmental
Protection
Agency's
(
hereafter
referred
to
as
EPA
or
the
Page
4
of
7
Agency)
"
Report
of
the
Food
Quality
Protection
Act
(
FQPA)
Tolerance
Reassessment
and
Risk
Management
Decision
for
Sodium
Cyanide."
This
document
is
also
known
as
a
Tolerance
Reassessment
Eligibility
Decision,
or
TRED.
EPA
issued
a
Reregistration
Eligibility
Decision
(
RED)
in
1994.
This
TRED
reassesses
the
tolerance
associated
with
sodium
cyanide
to
ensure
the
pesticide
meets
the
standards
of
FQPA.

The
Federal
Food,
Drug
and
Cosmetic
Act
(
FFDCA),
as
amended
by
FQPA,
requires
EPA
to
reassess
all
the
tolerances
for
registered
chemicals
in
effect
on
the
day
before
enactment
of
the
FQPA
on
August
3,
1996.
In
reassessing
these
tolerances,
the
Agency
must
consider,
among
other
things,
aggregate
risks
from
non­
occupational
sources
of
pesticide
exposure,
whether
there
is
increased
susceptibility
to
infants
and
children,
and
the
cumulative
effects
of
pesticides
with
a
common
mechanism
of
toxicity.
When
a
safety
finding
has
been
made
that
aggregate
risks
are
not
of
concern,
and
that
there
is
no
common
mechanism
of
toxicity
with
other
pesticides,
the
tolerances
are
considered
reassessed.
The
existing
tolerance
associated
with
sodium
cyanide
must
be
reassessed
in
accordance
with
FFDCA,
as
amended
by
FQPA.

II.
Background
Sodium
cyanide
is
not
currently
registered
for
any
food
or
feed
uses;
however,
there
is
one
Special
Local
Needs
(
SLN)
food/
feed
use
registration
under
Section
24(
C)
for
sodium
cyanide.
As
an
insecticide,
sodium
cyanide
is
used
in
California
as
a
source
of
hydrocyanic
gas
for
quarantine
fumigation
of
surface
pests
to
control
red
scale
on
fresh
market
citrus
bound
for
Arizona.
The
SLN
end­
use
product
is
formulated
as
a
granular
containing
98%
sodium
cyanide
as
the
active
ingredient.
It
is
applied
by
professional
applicators
only.
A
tolerance
for
residues
of
the
insecticide
hydrogen
cyanide
which
result
from
post­
harvest
fumigation
as
a
result
of
application
of
sodium
cyanide
is
established
at
50
ppm
in
or
on
citrus
fruit
under
40
CFR
§
180.130.
There
are
no
products
available
for
residential
application.

The
Agency
also
evaluated
the
potential
exposure
and
risk
from
cyanide
in
drinking
water
sources
in
Arizona
since
it
is
used
for
mining,
metal
finishing,
and
organic
chemical
industries.
The
Agency
obtained
monitoring
data
on
total
cyanide
levels
in
public
ground
and
surface
drinking
water
systems
throughout
the
State
of
Arizona
from
the
Arizona
Department
of
Environmental
Quality
(
ADEQ).
These
data
and
follow­
up
conversations
with
State
officials
indicate
that
total
cyanide
concentrations
are
non­
detectable
throughout
a
13­
year
period,
from
January
1993
through
June
2006.
Based
on
this
information,
drinking
water
exposure
is
expected
to
be
negligible
and
was
therefore
not
quantitatively
assessed
for
this
TRED.

Sodium
cyanide
is
used
as
a
predacide/
rodenticide
and
as
an
insecticide.
As
a
predacide/
rodenticide,
it
is
used
as
a
single
dose
poison
in
the
M­
44
ejector
device
to
control
animals
that
prey
upon
livestock
and
threatened
or
endangered
species
or
that
are
vectors
of
communicable
disease.
This
product
is
limited
to
use
only
by
trained
and
certified
applicators
under
the
direct
supervision
of
a
government
agency.

This
TRED
also
provides
an
assessment
of
and
risk
management
decision
for
worker
exposure
associated
with
the
use
of
sodium
cyanide
as
a
source
of
hydrocyanic
gas
for
fumigation
Page
5
of
7
of
surface
pests
on
citrus
which
was
not
addressed
in
the
1994
RED.
No
additional
mitigation
measures
are
required
for
workers
since
the
Agency's
occupational
assessment
resulted
in
MOEs
that
are
below
the
Agency's
level
of
concern.

III.
Links
to
the
Sodium
Cyanide
Assessments
Please
refer
to
the
human
health
and
drinking
water
risk
assessments
for
Sodium
Cyanide,
dated
July
10,
2006
and
February
7,
2006,
respectively,
for
details
on
the
risks
associated
with
the
use
of
Sodium
Cyanide.
These
documents
are
also
available
in
the
public
docket
EPA­
HQ­
OPP­
2006­
0352
located
on­
line
in
FDMS
at
http://
www.
regulations.
gov.

IV.
Regulatory
Determinations
A.
FQPA
Assessment
Supporting
Tolerance
Reassessment
Decision
The
FFDCA,
as
amended
by
FQPA,
directs
the
Agency
to
use
an
additional
tenfold
(
10X)
safety
factor
to
take
into
account
potential
pre­
and
post­
natal
toxicity
and
completeness
of
the
data
with
respect
to
exposure
and
toxicity
to
infants
and
children.
FFDCA
authorizes
the
Agency
to
modify
the
tenfold
safety
factor
only
if
reliable
data
demonstrates
that
the
resulting
level
of
exposure
would
be
safe
for
infants
and
children.

An
uncertainty
factor
(
UF)
of
100
was
applied
to
the
acute
RfD
based
on
application
of
a
10X
for
intraspecies
variation,
and
10X
for
lack
of
a
LOAEL,
steep­
dose­
response
curve,
and
severity
of
toxic
effect.
The
conventional
UF
of
10X
for
interspecies
extrapolation
was
not
applied
because
the
endpoint
selected
for
the
risk
assessment
was
from
a
human
study.

The
Agency
concluded
that
no
FQPA
Safety
Factor
is
necessary
to
protect
the
safety
of
infants
and
children
in
assessing
sodium
cyanide
exposure
and
risks
because
there
was
no
quantitative
increased
susceptibility
in
postnatal
offspring
toxicity
and
there
is
a
low
degree
of
concern
for
residual
uncertainties
for
pre
and/
or
post­
natal
susceptibility.

There
are
no
residual
uncertainties
identified
in
the
exposure
databases
and
the
Agency's
conservative
assessments
will
not
underestimate
the
potential
exposure
to
infants
and
children
resulting
from
the
use
of
sodium
cyanide.
Therefore,
the
FQPA
Safety
Factor
is
1X
for
the
hydrogen
cyanide
risk
assessment.

EPA
has
evaluated
the
dietary,
drinking
water,
residential,
and
occupational
risks
from
the
supported
registered
uses
of
sodium
cyanide
and
has
determined
that
there
is
a
reasonable
certainty
that
no
harm
to
any
population
subgroup
will
result
from
exposure
to
sodium
cyanide.
The
acute
dietary
exposure
estimates
for
food
for
the
U.
S.
population
and
all
population
subgroups
are
<
100
%
of
the
acute
Population
Adjusted
Dose
(
aPAD)
and
are
below
the
Agency's
level
of
concern
at
the
99.9th
percentile
of
exposure.
The
highest
estimated
exposure
was
to
children
1­
2
years
old
at
37%
of
the
aPAD.
A
chronic
dietary
exposure
assessment
was
not
performed
since
cyanide
is
extremely
acutely
toxic
at
doses
lower
than
those
at
which
chronic
toxicity
occurs.
Therefore,
the
tolerance
for
hydrogen
cyanide
established
at
40
CFR
§
180.300
is
now
considered
reassessed
Page
6
of
7
under
Section
408
(
q)
of
FFDCA.

EPA
has
determined
that
risk
from
exposure
to
sodium
cyanide
is
within
its
own
"
risk
cup."
In
other
words,
EPA
is
able
to
conclude
that
the
tolerance
residues
of
the
insecticide
hydrogen
cyanide
from
post­
harvest
fumigation
as
a
result
of
application
of
sodium
cyanide
meets
the
FQPA
safety
standards.
In
reaching
this
determination,
the
Agency
has
considered
the
available
information
on
the
potential
sensitivity
of
infants
and
children,
as
well
as
potential
aggregate
exposure
and
risk.
Because
there
are
no
residential
uses
and
exposure
through
drinking
water
is
negligible,
aggregate
exposure
is
equal
to
exposure
through
food.

B.
Cumulative
Assessment
Unlike
other
pesticides
for
which
EPA
has
followed
a
cumulative
risk
approach
based
on
a
common
mechanism
of
toxicity,
EPA
has
not
made
a
common
mechanism
of
toxicity
finding
as
to
hydrogen
cyanide
and
any
other
substances,
and,
hydrogen
cyanide
does
not
appear
to
produce
a
toxic
metabolite
produced
by
other
substances
which
have
tolerances
in
the
U.
S.
For
the
purposes
of
this
tolerance
reassessment
action,
therefore,
EPA
has
not
assumed
that
hydrogen
cyanide
has
a
common
mechanism
of
toxicity
with
other
substances.
For
information
regarding
EPA's
efforts
to
determine
which
chemicals
have
a
common
mechanism
of
toxicity
and
to
evaluate
the
cumulative
effects
of
such
chemicals,
see
the
policy
statements
released
by
EPA's
Office
of
Pesticide
Programs
concerning
common
mechanism
determinations
and
procedures
for
cumulating
effects
from
substances
found
to
have
a
common
mechanism
on
EPA's
website
at
http://
www.
epa.
gov/
pesticides/
cumulative/.

C.
Endocrine
Disruptor
Effects
EPA
is
required
under
the
FFDCA,
as
amended
by
FQPA,
to
develop
a
screening
program
to
determine
whether
certain
substances
(
including
all
pesticide
active
and
other
ingredients)
"
may
have
an
effect
in
humans
that
is
similar
to
an
effect
produced
by
a
naturally
occurring
estrogen,
or
other
such
endocrine
effects
as
the
Administrator
may
designate."
Following
recommendations
of
its
Endocrine
Disruptor
and
Testing
Advisory
Committee
(
EDSTAC),
EPA
determined
that
there
was
a
scientific
basis
for
including,
as
part
of
the
program,
the
androgen
and
thyroid
hormone
systems,
in
addition
to
the
estrogen
hormone
system.
EPA
also
adopted
EDSTAC's
recommendation
that
the
Program
include
evaluations
of
potential
effects
in
wildlife.
For
pesticide
chemicals,
EPA
will
use
FIFRA
and,
to
the
extent
that
effects
in
wildlife
may
help
determine
whether
a
substance
may
have
an
effect
in
humans,
FFDCA
authority
to
require
the
wildlife
evaluations.
As
the
science
develops
and
resources
allow,
screening
of
additional
hormone
systems
may
be
added
to
the
Endocrine
Disruptor
Screening
Program
(
EDSP).

In
the
available
toxicity
studies
on
hydrogen
cyanide,
there
was
no
estrogen
or
androgen,
mediated
toxicity.
Thyroid
effects
in
the
presence
of
liver
toxicity
were
seen
in
both
sexes
at
the
highest
dose
tested
in
the
chronic
dog
study.
When
additional
appropriate
screening
and/
or
testing
protocols
being
considered
under
the
Agency's
EDSP
have
been
developed,
hydrogen
cyanide
may
be
subjected
to
further
screening
and/
or
testing
to
better
characterize
effects
related
to
endocrine
disruption.
Page
7
of
7
D.
Tolerance
Reassessment
Summary
The
tolerance
for
residues
of
hydrogen
cyanide
in/
on
plant
commodities
that
is
currently
established
under
40
CFR
§
180.130
is
summarized
below.
The
tolerance
is
expressed
in
terms
of
hydrogen
cyanide
per
se.

Tolerance
Reassessment
Summary
for
Hydrogen
Cyanide
Commodity
Established
Tolerance
(
ppm)
Recommended
Tolerance
(
ppm)
Comment/
Correct
Commodity
Definition
Tolerances
listed
under
40
CFR
§
180.130
Fruit,
citrus
50
50
Fruit,
citrus,
group
10
Codex
Harmonization
Use
of
sodium
cyanide
as
a
fumigant
is
limited
to
citrus
treated
in
California
bound
for
Arizona
and
not
for
export.
Codex
maximum
residue
limits
(
MRLs)
do
not
currently
exist
for
hydrogen
cyanide.

V.
Data
Requirements
Residue
Chemistry
Data
Requirements
The
required
data
for
the
Sodium
Cyanide
TRED
are
as
follows:

 
860.1380
 
Storage
stability
data
for
citrus
 
860.1650
 
Analytical
standards
for
sodium
and
hydrogen
cyanide
are
not
currently
available
in
the
National
Pesticide
Standards
Repository.
Analytical
Reference
standards
of
sodium
and
hydrogen
cyanide
must
be
supplied
and
supplies
replenished
as
requested
by
the
Repository.

 
860.1500
 
Crop
Field
Trial
Residue
data
from
two
additional
studies
are
required
along
with
residue
data
on
whole
oranges.
A
detailed
explanation
of
the
modifications
to
EPA's
analytical
report
number
335.2
along
with
validation
of
this
method
at
the
reported
LOD
of
0.01
ppm
is
required.

Product
Chemistry
Data
Requirements
 
830.7050
 
Ultraviolet/
visible
Absorption
