Document ID: EPA-HQ-OPPT-2003-0016-0011
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2003-06-03T04:00Z

2003
OECD
Activities
Gary
Timm
and
Les
Touart
OECD
ED
Test
Guideline
Roles
Endocrine
Disrupters
Testing
and
Assessment
TF
Government
and
major
stakeholders
VMG­
Eco
Technical
experts
VMG­
Mam
Technical
experts
TEST
GUIDELINES
PROGRAM
National
Coordinators
Fish
Amphibian
Invertebrate
Bird
VMG
in
vitro
OECD
Activity
EDTA/
VMG
U.
S.
Member
countries
Stakeholders
(
BIAC,
ICAPO,
WWF)

EDMVS
U.
S.
experts
Possible
Modes
of
OECD
Involvement
in
Test
Method
Validation
1.
Coordinates
prevalidation
and
validation
2.
Lead
country
develops
prevalidation
data;

OECD
coordinates
and
directs
validation.

3.
Lead
country
develops
all
prevalidation
and
validation
data
for
OECD
guideline
development
4.
OECD
facilitates
information
exchange;
no
OECD
test
guideline
development.
Process
for
International
Guidelines
Follow
ICCVAM
requirements
for
method
validation
OECD's
Endocrine
Disruptor
Testing
and
Assessment
workgroup
will
be
primary
vehicle
for
deliberation
and
stakeholder
input
for
modes
1
and
2
on
previous
slide
EDMVS
will
be
kept
informed
and
will
be
asked
for
input
for
US
position
Process
for
International
Guidelines
US
will
be
lead
country
on
most
guidelines
Lead
country
coordinates
technical
work
US
volunteering
for
lead
country
because
we
have
resources
and
are
mandated
to
meet
schedule
Peer
review
by
letter
National
Coordinator
comment
process
Role
of
EDTA
Plan
and
execute
pre­
validation
and
validation
of
endocrine
test
procedures
Oversee
the
development
of
test
guidelines
based
on
the
validated
procedures
Provide
review
and
quality
control
of
documents
prior
to
submission
to
National
Coordinators
2003
OECD
Meeting
Schedule
VMG
non
animal
(
March
17­
18)

VMG
mammalian
(
April
14­
15)

VMG
eco
(
May
2)

Amphibian
Expert
Group
(
June
26­
27)

Fish
Drafting
Group
(
May
3,
September)

Invertebrate
Expert
Group
(
October)

Avian
Expert
Group
(
Spring
'
04)

EDTA
(
May
22­
23)
VMG
non
animal
(
VMG­
NA)
Agenda
Receptor
Binding
Assays
Aromatase
and
Steroidogenesis
Assays
Reporter
Gene/
Transcriptional
Activation
Assays
Discussion
of
QSARs
In
Vitro
Cell/
Tissue
Assays
VMG­
NA
Conclusions
and
Commitments
Receptor
binding
assays:

US
will
coordinate
the
development
and
validation
of
recombinant
ER
and
AR
assays
Switzerland
and
CERI
(
Japan)
are
interested
in
participating
in
the
validation
of
this
assay.

Steroidogenesis
and
aromatase:

US
will
pursue
development
of
a
cell­
based
assay
using
H295R
cell
line.

Japan
will
continue
the
development
of
an
aromatase
assay
with
the
KGN
cell
line.
VMG­
NA
Conclusions
and
Commitments
(
2)

Reporter
gene
assays:

Japan
has
completed
prevalidation
of
ERTA
system.
Protocol
for
validation
and
chemical
list
will
be
available
at
next
VMG
meeting.

Patent
issues.
What
would
validation
consist
of?

Japan
also
developing
ER 
and
AR
assays.

Thyroid:

US
will
revise
and
complete
ICAPO
DRP
on
in
vitro
thyroid
methods
CERI
will
run
a
version
of
the
FRLP­
5
cell
line
with
T3
VMG
mammalian
Agenda
Validation
of
the
uterotrophic
assay
Validation
of
the
Hershberger
Validation
of
the
enhanced
OECD
407
Thyroid
hormone
testing
Sharing
the
work
on
testing
and
assessment
Logic
of
OECD
Mammalian
Validation
Approach
VMG
adopts
initial
protocol
Lead
lab
and
participating
labs
identified
Phase
1
design
All
labs
perform
protocol
with
strong
positive
chemical
Check
lab
competence
and
endpoint
responsiveness
Refine
protocol
as
necessary
for
phase
2
trials
Phase
2
design
Challenge
protocol
with
weak
acting
chemicals
and
negatives
Conduct
blind
trials
Measure
interlaboratory
variability
Uterotrophic
Assay
An
in
vivo
assay
to
detect
estrogens
Phase
1
4
protocols
tested:
immature
oral,
immature
sc,

ovariectomized
3
day
sc,
OVX
7
day
sc.

19
laboratories;
ethynyl
estradiol
(
EE).

Phase
2
EE
was
used
as
reference
positive
at
two
doses
Dose
response
study
using
5
weak
estrogens:

bisphenol
A,
o,
p'­
DDT,
genistein,
methoxychlor,

nonylphenol
Uterotrophic
Assay
(
2)

Coded
single­
dose
study
 
Used
same
five
weak
agonists
 
Dibutyl
phathalate
included
as
negative
chemical
 
EE
included
as
strong
positive
Conclusions
The
uterotrophic
assay
is
reliable
and
relevant
 
All
protocols
detected
each
of
the
five
weak
estrogens
 
Four
different
comparisons
of
intra
and
interlaboratory
variability
were
made
Uterotrophic
Assay
(
3)

No
protocol
was
consistently
superior
 
SC
usually
more
sensitive
than
oral
except
when
first
pass
metabolism
was
required
for
activation
 
No
strain
differences
or
differences
in
diet
noted
so
long
as
phytoestrogen
intake
did
not
exceed
50
mg/
kg/
day
(
sensitivity
to
phytoestrogens:
OVX
rats<
immature
rats<
mice)

Recommend
peer
review
Independent
peer
review
panel;
solicited
by
NC
Review
by
mail
and
conference
call
Transparent
process
Hershberger
Assay
An
in
vivo
assay
to
detect
androgens
and
antiandrogens
Phase
1
17
laboratories;
testosterone
propionate
(
androgen),
flutamide
(
antiandrogen)

Phase
2
Testosterone
propionate
is
the
reference
androgen
AR
agonists:
TP,
17 ­
methyltestosterone,

trenbolone
AR
antagonists:
vinclozolin,
procymidone,
linuron,

p,
p'­
DDE,
flutamide
Hershberger
Assay
(
2)

5 ­
Reductase
Inhibitor:
Finasteride
Status
Phase
1
completed
2001
Phase
2
completed
May
2003
Phase
3
planned
to
complete
validation
by
Dec
2003
Peer
review
planned
for
March
2004
Phase
3
Testing
coded
chemicals
Testing
a
negative
chemical
Compare
weanling
males
with
castrated
males
Enhanced
OECD
407
OECD
407
28
day
repeat­
dose
study
in
adult
rodents
3
dose
levels
plus
control
Used
in
EU
and
Japan
for
new
chemicals
and
as
general
tox
screen
in
tiered
testing
ED
endpoints
Organ
wts.
(
sex
organs,
accessory
tissues,

thyroid)
Histopathology
Spermatology
(
motility,
morphology,
number)

Hormone
measurements
Enhanced
OECD
407
(
2)

Phase
1
7
laboratories
performed
phase
1
studies.

Flutamide
or
other
strong
endocrine
disruptor
Conclusions
from
phase
1
were
to
drop
sperm
motility
and
non­
thyroid
hormone
measures
Phase
2
10
chemicals
each
to
be
tested
in
2
laboratories:

 
6
strong:
Ethynyl
estradiol,
tamoxifen,
methyl
testosterone,
flutamide,
L­
thyroxine,
and
PTU
 
4
weak:
CGS
18320B1;
p,
p ­
DDE;
genestein,
nonyl
phenol
Split
design:
two
groups
of
5
animals
Enhanced
OECD
407
(
3)

Status
and
next
steps
Laboratory
studies
complete
Dec
2002
Data
compilation
complete
May
2003
Draft
final
report
December
2003
VMG
ecotoxicity
Agenda
Validation
of
the
Fish
Screen
Fish
Testing
(
Tier
II)

Validation
of
an
Amphibian
Screen
Thyroid
testing
Avian
Testing
Invertebrates
Fish
Screen
Vitellogenin
method
comparisons
Fathead
minnow
method
survey
completed
Zebrafish
and
medaka
method
surveys
in
progress
OECD
Phase
1A
All
three
species
(
fathead
minnow,
zebrafish,
medaka)

Non­
spawning
method
(
21­
day)

Three
endpoints
(
Vtg,
GSI,
gonad
histopathology)

Test
chemicals
­
17 ­
estradiol
and
trenbolone
Comparative
Evaluation
of
Assay
Methods
Fathead
minnow
only
Reproduction
assays
(
14
day
&
21
day)
and
Non­
spawning
(
14
day)

Test
chemicals
 
methoxychlor,
trenbolone,
flutamide,
fadrozole
Partial
life
cycle
assay
Proposed
by
Denmark,
given
high
priority
by
NCs
60­
90
day
test,
key
endpoint
=
sexual
differentiation
Fish
Screen
 
next
steps
Fish
Drafting
Group
meeting
in
September
Decide
on
assay
method
Plan
Phase
1B
 
multichemical
evaluation
of
selected
assay
Select
chemicals
for
Phase
1B
Fish
Testing
(
Tier
II)

Fish
Two­
generation
Test
DRP
(
US)
and
Fish
Two­
generation
TG
(
US)
circulated
for
comment
Fish
Life
Cycle
TG
(
Japan)
circulated
for
comment
Fish
Drafting
Group
(
meeting
in
September)

Plan
Phase
1A
of
validation
for
fish
testing
Amphibian
Screen
Revision
of
the
amphibian
screen
DRP
International
workshop
to
discuss
amphibian
methods
(
24­
25
June)

Amphibian
Expert
Group
meeting
(
26­

27
June)
Recommend
single
assay
to
advance
through
validation
Thyroid
Hormone
Disruption
Assays
DRP
Purpose
to
consider
the
applicability
of
existing
assays
under
development,

suggest
alternative
approaches,
and
identify
additional
data
needs
to
facilitate
a
consensus
direction.
Avian
Testing
Avian
two­
generation
toxicity
test
DRP
circulated
for
comment
Avian
dosing
study
in
progress
Additional
activities
One
generation
(
proven
breeder)
method
Two
generation
species
comparison
study
(
Japanese
quail
&
bobwhite
quail)

Avian
embryo
assay
(
range
finding
method)
Invertebrates
Recommend
revising
Mysid
Life
Cycle
DRP
to
include
Crustaceans
in
general
Recommend
invertebrate
testing
assays
be
expanded
to
include
annelids,
molluscs,
and
echinoderms
in
addition
to
arthropods
Recommend
considering
appropriate
invertebrate
screening
assays
 
focus
on
the
"
most
sensitive"
taxa