1
UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
MEMORANDUM
DATE:
October
1,
2004
SUBJECT:
Zinc
Pyrithione
(
Zinc
Omadine
®
)
:
Response
to
Public
Comments
from
International
Coatings,
Ltd
on
the
AD
Preliminary
Risk
Assessment
for
the
Reregistration
Eligibility
Decision
(
RED)
Document.
Chemical
No.
088002.
Case
No.
2480.
DP
Barcode:

FROM:
Deborah
Smegal,
MPH,
Toxicologist/
Risk
Assessor
Antimicrobials
Division
(
7510C)

THRU:
Norm
Cook,
Chief
Risk
Assessment
and
Science
Support
Branch
Antimicrobials
Division
(
7510C)

TO:
Tony
Kish
Regulatory
Management
Branch
I/
Team
33
Antimicrobials
Division
(
7510C)
2
Comments
from
AKZO
NOBEL,
International
Coatings,
Ltd.

Comment:
Exposure
of
residents
applying
antifouling
boat
paints
to
zinc
pyrithione.
The
commentor
believes
that
exposure
data
from
test
subjects
applying
a
bathroom
paint
with
a
paint
brush
is
not
an
appropriate
surrogate
for
exposure
to
antifouling
paints
applied
to
hulls
of
pleasure
boats.
The
commentor
also
concurs
that
the
Garrod
(
2000)
data
are
not
of
sufficient
quality
for
a
dermal
risk
assessment.
The
commentor
has
commissioned
an
exposure
study
"
Determination
of
dermal
and
inhalation
exposure
to
hazardous
substances
during
amateur
use
of
yacht
antifouling
coatings,
which
is
expected
to
be
submitted
to
the
Agency
on
December
31st,
2004.

Agency
Response:
The
Agency
will
evaluate
the
exposure
study,
and
revise
the
exposure
estimates
and
risks
for
antifouling
paint
exposures,
as
appropriate.

Comment:
Estimates
of
exposure
and
risks
to
residential
handlers
of
zinc
pyrithione
The
commentor
believes
it
is
important
to
use
a
dermal
penetration
value
for
zinc
pyrithione
in
an
antifouling
paint,
rather
than
using
the
dermal
penetration
factor
for
zinc
pyrithione
powder.
The
commentor
has
submitted
a
dermal
penetration
study
that
the
Agency
should
consider
in
finalizing
the
risk
assessment
for
residential
application
of
antifouling
paints.

Agency
Response:
The
Agency
will
evaluate
the
dermal
penetration
study
upon
final
submission
to
the
Agency.
Upon
cursory
review,
this
study
appears
to
be
an
in
vitro
human
skin
study.
It
is
the
Agency's
experience,
that
this
study
protocol
could
significantly
underestimate
dermal
absorption.
Thus,
the
Agency
is
not
currently
using
in
vitro
human
skin
studies
in
risk
assessment.
A
final
determination
will
be
made
about
the
merits
of
this
study,
following
completion
of
the
data
evaluation
review
(
DER)
by
the
Agency.

Comment:
Labelling
directions
on
cans
of
antifouling
paints
containing
zinc
pyrithione
available
to
residential
users.
The
risk
assessment
raises
concerns
over
inhalation
exposure
to
residential
users
of
antifouling
products
containing
zinc
pyrithione.
Application
by
spray
of
International
Paint's
antifouling
products
containing
zinc
pyrithione
by
residential
users
is
not
recommended,
and
this
is
reflected
in
directions
on
product
labels.

Agency
Response:
As
part
of
risk
mitigation,
the
Agency
intends
to
ensure
the
labels
are
revised
to
preclude
application
via
airless
sprayer.

Comment:
Occupational
exposure
and
risk
 
primary
occupational
handlers.
The
commentor
outlines
procedures
that
must
be
taken
when
handling
zinc
pyrithione
in
the
manufacturing
facility.

Agency
Response:
The
Agency
acknowledges
the
procedures
outlined
by
the
commentor.
