1
American
Chemistry
Council
12/
4/
02
Comments
on
the
Fish
Lifecycle
DRP
Richard
A.
Becker,
Ph.
D.,
DABT
American
Chemistry
Council
2
American
Chemistry
Council
12/
4/
02
Work
Needed
°
Clarify
goals
&
objectives
of
the
protocol
to
be
developed
as
this
will
affect
the
measurement
of
successful
validation.

°
Compare
efficiency
and
predicitivty
of
2­
gen
versus
partial
life
cycle
protocols,
and
consider
partial
life
cycle
(
PLC)
test
in
rainbow
trout.

°
Adapt
protocol
for
use
of
4
species,
or
substantiate
empirically
that
fat
head
minnows
(
FHMs)
are
superior
to
other
species.

°
Address
serious
statistical
concerns
regarding
type
1
errors,
group
sizes
and
endpoint
redundancy.

°
Remove
redundancy
and
address
lack
of
mechanistic
specificity
for
various
recommended
endpoints.

°
Address
irrelevance
of
water
column
exposure
for
some
chemicals
and
incorporate
flexibility
for
using
food
route.
3
American
Chemistry
Council
12/
4/
02
General
Comments
On
The
DRP
°
Reproduction
in
a
2­
gen
test
can
be
affected
by
non­
endocrine
mechanisms.
The
DRP
should
discuss
the
specificity
of
the
recommended
responses
for
endocrine
mechanisms
versus
frank
toxicity
(
e.
g.,
narcosis),
if
known.

°
Apical
tests,
e.
g.,
full
life
cycle
2­
gen
or
partial
life
cycle
(
PLC)
tests,
should
incorporate
a
dose
level
targeted
as
a
No
Effect
concentration.
4
American
Chemistry
Council
12/
4/
02
Premature
Selection
of
Test
Species
°
Focusing
validation
on
one
species
­
the
fathead
minnow
(
FHM)
­
may
be
more
economical
than
validating
4
species,
but
a
premature
choice
may
trade
short­
term
economy
for
long­
term
expense.

°
Multigeneration
and
partial
life
cycle
test
periods
would
likely
be
weeks
or
months
shorter
in
sheepshead
minnow
(
SHM),
medaka
or
zebrafish
than
in
FHM.
5
American
Chemistry
Council
12/
4/
02
Species
Selection:
Key
Issues
°
No
indication
that
one
species
yields
the
most
consistent,
sensitive
and
specific
test
for
hormonally
active
agents
(
HAAs)

°
The
longer
reproductive
cycle
of
fathead
minnows
may
result
in
additional
assay
costs.

°
The
greater
variability
in
fathead
reproductive
parameters
likely
requires
larger
group
sizes
for
adequate
statistical
power.

°
The
proposed
2­
gen
protocol
should
allow
use
of
any
of
the
4
species
(
FHM,
SHM,
zebrafish,
medaka).
6
American
Chemistry
Council
12/
4/
02
What
is
Gained
from
a
Two­
Gen
Versus
One­
Gen
Test?

°
For
non­
endocrine
effects,
Partial
Life
Cycle
(
PLC)
tests
appear
to
be
nearly
as
useful
and
more
efficient
than
Full
Life
Cycle
(
FLC)
tests,
e.
g.
Macek
&
Sleight
(
1977);
Dionne
&
Kiamos
(
1994).

 
Reported
that
early
life
stage
exposure
correctly
predicted
effects
for
80%
of
chemicals
tested.

 
Were
the
remaining
20%
predicted
within
an
order
of
magnitude
dose?
7
American
Chemistry
Council
12/
4/
02
PLC
Versus
FLC
°
Partial
life­
cycle
(
e.
g.,
OECD)
versus
multi­
gen
tests
have
not
been
rigorously
compared
for
ability
to
detect
HAAs
or
for
predicting
effects
in
the
field.

°
Endocrine
endpoints
can
be
routinely
measured
in
standardized
PLC
protocols
(
e.
g.,
OECD)
and
may
identify
HAAs
as
effectively
and
more
efficiently
than
multigeneration
tests.

°
A
PLC
test
also
measures
endpoints
relevant
to
the
population,
such
as
the
number
of
eggs/
female/
day,
fertilization,
hatching
success,
and
GSI.
8
American
Chemistry
Council
12/
4/
02
PLC
Test
in
Rainbow
Trout
(
RT)
deserves
consideration
°
RT
have
a
long
history
of
regulatory
use
and
acceptance.

°
Endocrine
feedback
control
is
better
understood
in
salmonids
(
e.
g.,
RT)
than
in
species
considered
in
DRP.

°
Synchronous
reproduction
strategies
are
important
for
many
species
(
e.
g.,
RT)
but
ignored
in
species
considered
in
DRP.

°
VTG
analysis
is
fully
developed
in
RT.
9
American
Chemistry
Council
12/
4/
02
Statistical
Considerations
°
Great
variability
in
egg
production
reduces
the
statistical
power
of
the
2­
gen
test.
The
DRP
should
give
greater
consideration
to
the
use
of
regression
analysis
to
determine
percent
Effective
Concentrations
(
e.
g.,
EC20)
and
incorporate
such
methods
into
the
final
protocol.

°
The
DRP
should
discuss
the
type
1
error
rate
expected
at
typical
a
values
(
e.
g.,
0.05
or
0.01)
given
that
60
­
80
NOEC
determinations
are
recommended
for
the
2­
gen
test
in
FHM.
10
American
Chemistry
Council
12/
4/
02
Exposure
Considerations
°
Exposure
via
the
food
should
be
considered
for
hydrophobic,
bioaccumulative
chemicals.

 
Many
suspected
HHAs
are
hydrophobic
and
bioaccumulative
°
Maintenance
of
constant
exposure
concentrations
in
a
long­
term
test
is
environmentally
unrealistic,
especially
for
chemicals
that
hydrolyze
rapidly.
Flexibility
should
be
incorporated
into
the
protocol
to
allow
environmentally
relevant
exposures.
11
American
Chemistry
Council
12/
4/
02
Endpoint
Considerations
°
Sperm
quality,
egg
viability,
and
spawning
behavior
are
redundant
with
hatching
success
or
egg
production
­
those
endpoints
should
only
be
assessed
if
there
is
a
specific
indication
that
these
mechanisms
of
action
are
important.

°
Continuous
monitoring
of
embryonic
development
is
unnecessary
in
a
2­
gen
test.
Significant
effects
on
egg
hatchability
and
larval
survival
would
be
immediately
apparent.

°
Sex
steroid
and
thyroid
hormone
production
are
not
useful
in
a
FLC
test;
emphasis
should
be
on
reproductive
results.
12
American
Chemistry
Council
12/
4/
02
International
Cooperation
°
Must
have
international
cooperation
working
through
OECD
EDTA
°
Internationally
harmonized
standardized
&
validated
methods
 
Mutual
acceptance
of
data
 
Animal
welfare
