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Unit two
Text:
Cancer & Chemicals
-Are We
Going Too Far?
Marla Cone
Last
year,
California
governor
George
Deukmejian
called
together
many
of
the
state's
best
scientific
minds
to
begin
implementing
Proposition
65,
the
state's
Safe
Drinking
Water
and Toxic Enforcement
Act. This new law bans industries from
discharging chemical suspected of
causing cancer (carcinogens)
or
birth
defects
into
water
supplies.
Some
claim
it
will
also
require warning labels
on everything that might cause cancer.
A day of esoteric science and
incomprehensible jargon was
predicted.
But
Bruce
Ames,
chairman
of
the
department
of
biochemistry
at
the
University
of
California
at
Berkeley,
had
plans to liven the proceedings.
Walking into the room, Ames looked like
the quintessential
scientist: wire-
rimmed bifocals, rumpled suit, tousled hair and a
sallow
complexion
that
showed
he
spent
more
time
in
his
laboratory
than
in
the
California
someone
intoned
about
the
mechanisms
of
carcinogenesis,
Ames
began
to
interject his own views.
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whole
world
is
chock-full
of
carcinogens,
Ames
declared.
“
A beer, with its 700 parts per billion
of formaldehyde
and
five
parts
per
100
of
alcohol
is
a
thousand
times
more
hazardous than anything
in the water. If you have beer on your
breath, does that mean you have to warn
everyone who comes
within ten feet of
you?
In an era when
headlines shout about the latest cancer scare,
Ames
has
a
different
message:
the
levels
of
most
man-made
carcinogens
are
generally
so
low
that
any
danger
is
trivial
compared with the levels of natural
carcinogens.
Ames is
not a
quack. At age 59, he is
one of the
nation's
most
respected
authorities
on
carcinogenesis.
His
resume
is
packed
with honors, including the Charles. Mott Prize
from the
General
Motors
Cancer
Research
Foundation,
one
of
the
most
prestigious
awards
in
cancer
research,
and
membership
in
the
National Academy of his critics say
the Ames test
—
his
simple,
inexpensive
laboratory
procedure
that
helps
determine
whether
a
substance
might
cause
cancer
—
is
a
remarkable achievement.
But
Ames
slaughters
sacred
cows.
He's
taking
on
the
environmental
movement,
which
some
have
called
the
single
most
important
social
movement
of
the
20th
century.
In
April
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1987,
for
instance,
he
and
two
colleagues,
Renae
Magaw
and
Lois Swirsky Gold, published a report
in Science magazine that
ranked
various
possible
cancer
on
animal
tests
of
nearly 1,000 chemicals, the data show
that daily consumption of
the
average
peanut-butter
sandwich,
which
contains
traces
of
aflatoxin
(a
naturally
occurring
mold
carcinogen
in
peanuts),
is 100 times more
dangerous than our daily intake of DDT from
food,
and
that
a
glass
of
the
most
polluted
well
water
in
the
Silicon
Valley is 1,000 times less of cancer
risk than a glass of
wine
or
beer
's
not
advising
people
to
stop
consuming
peanut-butter,
beer
and
wine.
What
he's
saying
is
that
most
cancer
risks created by man are trivial compared with
everyday
natural risks, and it's not
clear how many of these are real risks.
Both types distract
attention from such enormous risk
factors
as tobacco.
Ames's
cancer
research
began
about
25
years
ago
over
a
bag
of
potato
chips.
Ames,
then
conducting
research
for
the
National
Institutes
of
Health
in
Maryland,
was
reading
the
ingredients on the bag. It struck him
that no one knew what each
chemical did
to human genes, and there was no easy way to find
out.
At that time,
scientists testing for carcinogenicity had to set
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