1
September
2005
EPA
738­
F­
05­
005
ENDOTHALL
RED
FACT
SHEET
Pesticide
Reregistration
All
pesticides
sold
or
distributed
in
the
United
States
must
be
registered
by
EPA,
based
on
scientific
studies
showing
that
they
can
be
used
without
posing
unreasonable
risks
to
people
or
the
environment.
Because
of
advances
in
scientific
knowledge,
the
law
requires
that
pesticides
which
were
first
registered
before
November
1,
1984,
be
reregistered
to
ensure
that
they
meet
today's
more
stringent
standards.

In
evaluating
pesticides
for
reregistration,
EPA
obtains
and
reviews
a
complete
set
of
studies
from
pesticide
producers,
describing
the
human
health
and
environmental
effects
of
each
pesticide.
To
implement
provisions
of
the
Food
Quality
Protection
Act
(
FQPA)
of
1996,
EPA
considers
the
special
sensitivity
of
infants
and
children
to
pesticides,
as
well
as
aggregate
exposure
of
the
public
to
pesticide
residues
from
all
sources,
and
the
cumulative
effects
of
pesticides
and
other
compounds
with
common
mechanisms
of
toxicity.
The
Agency
develops
any
mitigation
measures
or
regulatory
controls
needed
to
effectively
reduce
each
pesticide's
risks.
EPA
then
reregisters
pesticides
that
meet
certain
human
health
and
safety
standards
and
can
be
used
without
posing
unreasonable
risks
to
human
health
and
the
environment.

When
a
pesticide
is
eligible
for
reregistration,
EPA
explains
the
basis
for
its
decision
in
a
Reregistration
Eligibility
Document
(
RED)
document.
This
fact
sheet
summarizes
the
information
in
the
RED
document
for
the
pesticide
endothall,
case
number
2245.

Uses
 
Endothall
is
applied
as
either
a
dipotassium
salt
or
an
N,
N­
dimethylalkylamine
salt.
Endothall
acid
is
not
directly
applied
to
use
sites;
it
is
formed
as
a
breakdown
product
resulting
from
application
of
the
salt
forms.
 
Endothall
is
used
as
an
aquatic
herbicide
to
control
submerged
aquatic
vegetation
and
algae
in
lakes,
ponds,
and
irrigation
canals.
 
Endothall
is
also
used
as
a
desiccant
on
potatoes,
hops,
cotton,
clover,
and
alfalfa.
 
Endothall
has
one
biocide
use
to
control
mollusks
and
algae
in
cooling
towers/
systems.
 
In
terms
of
pounds
used,
endothall
is
most
readily
used
as
an
aquatic
herbicide.
For
terrestrial
uses,
the
majority
of
use
is
on
potatoes
(
approximately
5%
crop
treated)
and
cotton
(
less
than
2.5%
crop
treated).
Of
the
two
forms
of
endothall,
the
N,
N­
dimethylalkylamine
salt
accounts
for
the
most
use.
2
Health
Effects
 
Endothall
a
Toxicity
Category
I
by
the
oral
and
ocular
routes,
and
is
a
skin
sensitizer.
For
dermal
and
inhalation
toxicity,
endothall
is
categorized
as
mildly
toxic.
 
Endothall
is
not
a
neurotoxicant,
nor
does
it
induce
developmental
toxicity.
 
Endothall
is
classified
as
"
not
likely
to
be
carcinogenic
to
humans"
and
has
no
mutagenic
potential.
 
Endothall
does
not
bioaccumulate.
 
Chronic
dietary
risks
(
food
and
drinking
water)
do
not
exceed
the
Agency's
level
of
concern,
although
drinking
water
risk
for
infants
less
than
one
year
old
is
at
the
level
of
concern.
 
Several
occupational
exposure
scenarios
are
of
concern
to
the
Agency.
Mitigation
to
address
these
concerns
is
listed
below.

Risk
Mitigation
The
following
risk
mitigation
measures
are
required
for
endothall
to
address
risks
of
concern.
 
To
ensure
dietary
(
food
and
water)
risks
are
below
the
Agency's
level
of
concern,
600
foot
set
backs
from
drinking
water
intakes
are
required.
 
To
protect
workers,
the
following
mitigation
measures
are
required:
o
For
workers
mixing
and
loading
liquid
formulations
for
aerial
applications
to
terrestrial
sites,
workers
are
required
to
wear
an
80%
(
PF5)
respirator
(
NIOSH
TC­
21C).
o
For
workers
mixing,
loading,
and
applying
liquid
formulations
for
aquatic
applications,
workers
must
wear
an
80%
(
PF5)
respirator
(
NIOSH
TC­
21C).
o
For
workers
loading
and
applying
granular
formulations
for
aquatic
uses,
workers
are
required
to
wear
a
90%
(
PF10
elastomeric
half
face
respirator
with
appropriate
cartridge)
respirator
(
BIOSH
TC­
23C
or
NIOSH
TC­
14G).
Specific
label
language
will
include:


During
granular
applications,
the
respirator
need
not
be
worn,
provided
that
the
pesticide
is
applied
in
a
manner
(
such
as
aerial
application
or
subsurface
release
or
from
the
rear
of
a
vessel
that
is
moving
into
the
wind)
that
the
applicator
will
have
no
contact
with
the
pesticide.


During
liquid
applications,
the
respirator
need
not
be
worn,
provided
that
the
pesticide
is
applied
in
a
manner
(
such
as
direct
metering
or
subsurface
release
from
the
rear
of
a
vessel
that
is
moving
into
the
wind)
that
the
applicator
will
have
no
contact
with
the
pesticide.
o
For
residential
uses
of
endothall,
the
following
statement
is
required
on
labels:
"
Consult
local
fish
and
game
agency
and
water
control
authorities
before
applying
this
product.
Permits
may
be
required
to
treat
such
water."
3
o
The
Agency
is
requiring
that
labels
for
the
dipotassium
salt
form
of
endothall
specify
different
rates
for
different
size
applications.
The
language
is
as
follows:


"
Only
use
higher
rates
when
making
treatments
to
small
areas
with
an
increased
potential
for
rapid
dilution
or
when
making
long
and
narrow
applications
such
as
for
boat
lanes
or
shoreline
treatments
where
dilution
may
reduce
the
exposure
of
plants
and
the
herbicide."


"
Use
the
lower
rates
for
large
contiguous
treatment
blocks
or
in
protected
areas
such
as
coves
where
reduced
water
movement
will
not
result
in
rapid
dilution
of
the
herbicide
from
the
target
treatment
area
or
when
treating
entire
lakes
or
ponds."
o
The
Agency
is
requiring
that
N,
N­
dimethylalkylamine
products
used
in
lakes,
ponds,
streams,
and
other
bodies
of
water
are
limited
to
applications
to
control
algae,
Hygrophila,
Vallisneria,
Hydrilla,
Cabomba,
bur
weed,
Elodea
canadensis
and
Brazilian
elodea.

Regulatory
Decision
EPA
has
determined
that
all
products
containing
endothall
as
the
active
ingredient
are
eligible
for
reregistration,
provided
changes
specified
in
the
endothall
RED
are
incorporated
in
product
labeling
and
additional
data
identified
in
Section
V
of
the
RED
confirms
this
decision.

For
More
Information
For
more
information
about
EPA's
pesticide
reregistration
program,
the
endothall
RED,
or
reregistration
of
individual
products
containing
endothall,
contact
Anne
Overstreet
in
the
Special
Review
and
Reregistration
Division
(
7508C),
Office
of
Pesticide
Programs,
US
EPA,
Washington
DC
20460,
telephone
703­
308­
8068.

For
information
about
the
health
effects
of
pesticides,
or
for
assistance
in
recognizing
and
managing
pesticide
poisoning
symptoms,
please
contact
the
National
Pesticide
Information
Center
(
NPIC).
Call
toll­
free
1­
800­
858­
7378,
from
6:
30
am
to
4:
30
pm
Pacific
Time,
or
9:
30
am
to
7:
30
pm
Eastern
Standard
Time,
seven
days
a
week.
The
NPIC
internet
address
is
http:
npic.
orst.
edu.
