Reference
Chemicals
Used
in
EDSP
Tier
1
Prevalidation
Studies
Prepared
for
the
Endocrine
Methods
Validation
Subcommittee
August
19,2003
NOTE:
The
chemicals
contained
in
this
document
were
selected
as
reference
chemicals
for
prevalidation
studies
in
the
EDSP
assay
validation
program
because
they
produced
a
well­
documented
positive
response
in
one
or
more
Tier
1
assays
by
an
identified
mode
of
action.
Some
chemicals
may
act
by
more
than
one
mode
of
action.
It
should
be
noted
that
this
is
not
intended
to
be
a
list
of
endocrine
disruptors,
and
it
should
not
be
concluded
a
chemical
on
this
list
is
necessarily
an
endocrine
disruptor
since
that
designation
also
requires
an
association
with
an
adverse
effect
identified
in
a
Tier
2
study.
Although
some
chemicals
on
this
list
have
been
studied
extensively,
others
have
not
been
studied
in
tier
2
assays.

For
the
most
part,
test
results
from
the
literature
have
not
been
included
in
these
tables
as
such
studies
raise
questions
about
comparability
of
protocols
and
data.
Thus,
the
entries
in
the
tables
represent
studies
conducted
in
the
EDSP
validation
program,
EPA
ORD
laboratories,
and
the
OECD
assay
validation
program.
The
exception
to
this
are
the
studies
shown
for
the
adult
or
intact
male
assay,
which
was
developed
by
the
US
chemical
industry
and
tested
in
various
industry
laboratories.

The
chemicals
used
in
prevalidation
appear
in
the
following
tables
grouped
into
five
modes
of
action:
estrogen
receptor
binding,
androgen
receptor
binding
and
5"­
reductase
inhibition,
inhibition
of
steroidogenesis,
inhibition
of
aromatase,
and
neuroendocrine.
Some
chemicals
appear
more
than
once
because
they
act
by
more
than
one
mode
of
action.
Questions
for
the
EDMVS
Regarding
Reference
Chemicals
1.
Does
the
EDMVS
agree
with
the
EPA's
decision
to
limit
consideration
of
data
to
the
studies
conducted
in
the
EDSP
validation
program,
EPA
ORD
laboratories,
the
OECD
assay
validation
program,
and
for
the
adult
male,
the
US
chemical
industry
laboratories?

2.
The
ensure
that
the
assays
selected
to
comprise
the
tier
1
battery
cover
the
known
modes
of
action
in
a
comprehensive,
complementary
and
efficient
fashion,
EPA
has
grouped
the
chemicals
used
in
prevalidation
into
five
modes
of
action.
How
many
chemicals
should
be
selected
to
compare
assays
across
modalities?

3.
What
additional
chemicals
should
be
chosen
for
specific
assays
during
validation
to
facilitate
comparisons?
