Submission at the at the Workshop on Risk Assessment in Regulatory Policy Analysis (RIA), Session 10, Mexico, 9-11 June 2014. Further information is available at http://www.oecd.org/gov/regulatory-policy/

1. Comparing
Risks
–
Eating
Fish
In
2004,
the
U.S.
Food
and
Drug
Administration
(FDA)
and
the
U.S.
Environmental
Protection
Agency
(EPA)
issued
an
advisory
about
the
risks
of
methylmercury
(MeHg)
in
fish
and
shellfish1.
The
goal
was
minimizing
the
likelihood
that
women
of
childbearing
age
would
ingest
excessive
MeHg
while
still
benefiting
from
consumption
of
fish.
MeHg
is
a
potential
developmental
neurotoxicant,
causing
cognitive
deficits
in
children
exposed
in
utero
and
may
have
other
adverse
effects
including
heart
attacks
in
men.
At
the
same
time,
fish
consumption
provides
a
rich
source
of
omega-­‐3
fatty
acids.
Omega-­‐3
fatty
acids
are
linked
to
a
number
of
health
benefits
including
reduced
risk
of
heart
attack
and
stroke
(primarily
in
older
men)
and
improved
cognitive
function
in
infants.
EPA
and
FDA
did
not
conduct
a
formal
analysis
of
the
magnitude
of
the
benefits
(and
disbenefits)
that
might
occur
from
the
advisory.
The
impact
of
the
advisory
on
fish
consumption
by
women
of
childbearing
age
and
the
rest
of
the
population
was
unknown.
Evidence
for
MeHg
harm
to
the
developing
fetus
comes
from
prospective
epidemiologic
studies
for
populations
with
high
fish
consumption
in
New
Zealand,
the
Faroe
Islands
and
the
Seychelles
Islands.
The
studies
reach
different
conclusions
with
the
NZ
and
Faroe
Island
studies
finding
subtle
cognitive
deficits
in
the
children
of
mothers
with
the
greatest
MeHg
exposure
and
the
Seychelles
study
finding
no
effects.
Some
epidemiology
studies
link
MeHg
to
heart
attacks,
although
the
findings
are
mixed.
The
benefits
of
omega-­‐3
fatty
acids
are
based
on
both
epidemiologic
studies
and
clinical
trials
(for
the
benefit
to
infant
cognitive
function).
The
results
are
quite
consistent
across
studies.
If
you
were
asked
to
conduct
an
impact
assessment
of
a
fish
consumption
advisory2:
• How
would
you
decide
which
health
outcomes
to
include
and
which
to
exclude?
• Would
it
matter
to
you
that
some
health
outcomes
have
consistent
evidence
for
causality
and
some
do
not?
If
so,
how
would
you
incorporate
this
into
your
analysis?
• How
would
you
think
about
quantitatively
comparing
very
different
health
outcomes
like
heart
attacks,
strokes
or
cognitive
effects
in
infants?
• Does
it
matter
that
different
populations
bear
the
risks
or
get
the
benefits
of
fish
consumption?
1
http://www.fda.gov/food/resourcesforyou/consumers/ucm110591.htm
2
Cohen,
J.T.
,
Bellinger,
D.,
Connor,
W.E.,
Kris-­‐Etherton,
P.M.
,
Lawrence,
R.S.
,
Savitz,
D.S.
,
Shaywitz,
B.
,
Teutsch,
S.M.
,
Gray,
G.
(2005)
A
Quantitative
Risk-­‐Benefit
Analysis
of
Changes
in
Population
Fish
Consumption.
American
Journal
of
Preventive
Medicine
29:325-­‐334