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NEIL DEGRASSE TYSON:
Once there was a man
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who went searching
for the true age of the Earth.
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In his struggles
to discover it,
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he stumbled on a grave threat.
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Beautiful spring day,
Pasadena, California.
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1966.
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Business is booming,
life's good.
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Except for one man,
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a geochemist named
Clair Patterson,
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known as Pat.
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He knows that everyone he sees
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is in danger
from an invisible menace.
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And he's determined
to put a stop to it,
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no matter what the cost.
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¶ ¶
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¶ ¶
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¶ ¶
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You can't really tell
Pat Patterson's story
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without going all the way back
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to the time long
before the Earth,
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our home, was built,
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when the stars brought forth
its substance.
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Iron.
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For the planet's molten core.
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Oxygen.
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For the rocks and the water
and the air.
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Carbon.
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For diamonds. And life.
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(boom)
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A star is born,
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ours.
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For the first few million
years, things ran smoothly
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as dust grains snowballed into
progressively larger objects.
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But once these objects
grew massive enough
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to have sufficient gravity...
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...they began pulling each
other into crossing orbits.
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This is how our world looked
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when it was new.
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No part of the Earth's surface
could survive intact
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from that time to the present.
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So, with all its birth and
early childhood records erased,
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how could we ever hope to know
with any certainty
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the true age of our world?
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People have been wondering
about this since antiquity.
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In 1650 Archbishop
James Ussher of Ireland
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made a calculation
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that seemed
to settle the question.
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Like almost everyone else
of his time and his world,
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he accepted the biblical
account of creation
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as authoritative.
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But the Bible does not give
exact years,
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so Ussher searched for an event
in the Old Testament
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that corresponded
to a known historical date.
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He found it
in the Second Book of Kings,
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the death of the Babylonian
ruler Nebuchadnezzar
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in 562 B.C.
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Ussher added up the generations
of the prophets
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and the patriarchs,
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the 139 "begats"
of the Old Testament,
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between Adam and the time
of Nebuchadnezzar,
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and discovered
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that the world began
on October 22
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in the year 4004 B.C.
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at 6:00 p.m.
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It was a Saturday.
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Archbishop Ussher's chronology
was taken as gospel
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in the Western world
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until we turned to another book
to find the age of the Earth,
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the one that was written
in the rocks themselves.
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Most of the rock layers
in the walls of the Grand Canyon
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are made of sediments,
deposited as fine grains
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in a time when this part
of the world was a sea.
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Over eons, the sediments
were compressed into rock
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under the weight
of succeeding layers,
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with the oldest ones
at the bottom.
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Pick a layer, any layer.
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(rumbling)
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How about that one?
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Once upon a time, there must
have been shallow water here.
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Back in the Precambrian period,
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about a billion years ago,
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there was only one kind
of life.
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These blue-green bacteria
were busy harvesting sunlight
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and making oxygen.
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For them, it was just
a waste product,
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but for the animals who evolved
later, including us,
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it was the breath of life.
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Okay. Pick another layer.
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How about that one?
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This layer is known
as the Bright Angel Shale.
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It formed
about 530 million years ago.
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These tracks were left
260 million years ago.
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So you want to know
the age of the Earth?
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Just figure out how long
it took to deposit each layer
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and then, instead
of counting the "begats,"
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add up all the layers.
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Easy, right?
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Just one problem: we know
from observing this process--
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because it still happens today
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in oceans and lakes
around the world--
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that sediments can be laid down
at widely different rates.
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It usually happens very slowly,
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say a foot of sediment
per 1,000 years.
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But when there's
a rare catastrophic flood,
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it can happen much faster,
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as much as a foot
in just a few days.
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Many geologists tried
this method
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to calculate
the age of the Earth.
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They used the Grand Canyon
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and other sedimentary sequences
around the planet.
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But their answers ranged
too widely to be of much use,
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anywhere between three million
years and 15 billion.
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And there were other problems
with this method:
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even the deepest layers of rock
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are not the oldest things
on Earth.
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Why? Because not even rocks
could survive
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the Earth's violent infancy.
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In space it's another story.
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DEGRASSE TYSON:
Are there any mementos
from when the Earth was born,
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objects that could possibly
tell us its true age?
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I know a place where the unused
bricks and mortar left over
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from the creation of
our solar system can be found.
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It lies between the orbits
of Jupiter and Mars.
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Here is the stuff
of the newborn Earth,
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adrift in cold storage,
unchanged
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ever since that time.
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A million or so years ago,
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a large asteroid happened
to jostle a much smaller one,
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sending it on a new trajectory,
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a collision course
that ended one night
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some 50,000 years ago.
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(hooting)
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It must have shattered
the peace of the Grand Canyon
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as it sailed overhead...
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...to blast out this crater
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in what would one day be known
as Arizona.
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Fragments of the iron asteroid
that made this crater
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have survived intact.
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If we just knew how long ago
that iron was forged,
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we'd know the age
of the solar system.
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Including the Earth.
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But how could we know that?
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Pick a rock.
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Any rock.
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How about that one?
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Some atoms in this rock
could be radioactive,
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which means they
spontaneously disintegrate
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and become other elements.
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A uranium atom
first becomes a thorium atom.
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On average, it takes
a few billion years.
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The thorium
is much more unstable.
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In less than a month
it turns into protactinium.
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A minute later, protactinium
becomes something else.
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The atom undergoes ten more
nuclear transmutations...
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until it reaches the last stop
on the decay chain:
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a stable atom of lead.
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And lead it will remain...
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for eternity.
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In the 20th century there was
a huge effort, lasting decades,
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to measure the time it takes
for each radioactive element
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to transmute
into another element.
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Physicists discovered that the
atoms of each unstable element
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decay at a constant rate.
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The nucleus of an atom
is a kind of sanctuary,
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immune to the shocks and
upheavals of its environment.
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Hit it with a hammer.
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(clang)
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Boil it in oil.
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Vaporize it.
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The nuclear clock
goes on ticking,
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keeping an absolute
standard of time
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that does not look
to the Sun and the stars.
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What better way to find
the true age of the Earth
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than with the uranium atom?
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If you knew what fraction
of the uranium in a rock
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had turned into lead,
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you could calculate
how much time had passed
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since the rock was formed.
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But there's a problem.
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The rocks in the Earth that
were present when it was formed
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are no more.
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They've all been crushed,
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melted, remade.
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There is a way to calculate
the amount of lead
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that was present
from the beginning.
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It's a gift from the heavens:
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meteorites.
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This one-- a fragment of the one
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that made this giant crater--
was ideal.
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The amount of lead
deep inside this meteorite
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is exactly the same
as when Earth formed.
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Since you know the constant
rate of uranium decay,
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that should give you
the age of the meteorite,
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which was made
at the same time as the Earth.
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All you had to do was measure
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the amount of lead
in meteorites.
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Easy, right?
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A scientist named
Harrison Brown,
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at the University of Chicago,
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first understood this in 1947.
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He chose a young graduate
student, Clair Patterson,
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to do the work.
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Patterson couldn't possibly
know how this assignment
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would alter
the course of his life...
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and ours.
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What seemed
like pure scientific research
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turned out to be so much more.
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(crying)
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DEGRASSE TYSON:
Clair Patterson, son
of a letter carrier from Iowa,
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was rebellious by nature
and not very good in school.
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But he was
a natural born scientist.
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A geologist
named Harrison Brown
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gave Patterson what seemed
like a straightforward
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scientific assignment.
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First off, Pat...
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You mind if I
call you Pat?
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Now, I know you're
no geologist--
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probably couldn't tell
granite from feldspar--
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but I hear you really
know your way
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00:15:04,770 --> 00:15:06,871
around a mass
spectrometer, Pat.
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Good. You married, Pat?
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Yeah, Laurie. Yeah,
she-she's a chemist, too.
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Uh, we worked on
the Manhattan Project together,
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at Oak Ridge.
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Good. Okay, well, first
thing you need to know:
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there are these tiny
crystals called zircons.
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Real small, size of a pinhead,
tight as a drum and tough.
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Nothing gets in
or out of 'em.
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And I'm talking for
billions of years.
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We know how old these grains are
because we've already
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dated the rocks they came from.
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00:15:35,367 --> 00:15:38,503
Each little zircon has only
a few parts per million
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of uranium inside, and that
uranium is decaying
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00:15:41,807 --> 00:15:44,776
to even tinier amounts of lead.
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Now, you figure out how
to measure that lead,
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and you'll know how to
do it for a meteorite.
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You think you can do that, Pat?
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Yeah. Yeah,
I-I don't see why not.
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Good, because when you do,
you'll be the first man
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to know the age
of the Earth.
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And you'll be famous.
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And you'll see:
it'll be easy.
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Duck soup.
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While Patterson tried to measure
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the trace amounts of lead
in the zircon grains,
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00:16:32,758 --> 00:16:35,093
another grad student,
George Tilton,
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was measuring the amount
of uranium in the same grains.
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All Patterson had to do
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was measure the amount of lead
with equal accuracy.
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She's all yours, Pat.
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Measured it six
times. Same result:
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00:16:48,307 --> 00:16:49,874
3.2 parts per million.
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Yeah, nice going,
George, thanks.
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DEGRASSE TYSON:
Tilton's results
were always the same.
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But Patterson's results on the
lead content of the same grains
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were wildly inconsistent.
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This made no sense.
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Could the lab have
been contaminated
259
00:17:23,309 --> 00:17:26,477
by previous experiments
with lead?
260
00:17:26,512 --> 00:17:28,512
Maybe it was
the naturally high amounts
261
00:17:28,514 --> 00:17:32,250
of lead in the environment that
were messing up his results.
262
00:17:37,456 --> 00:17:39,123
Patterson did
everything he could
263
00:17:39,158 --> 00:17:42,360
to cleanse the lab of any lead.
264
00:17:46,331 --> 00:17:48,316
(electric whirring)
265
00:17:52,171 --> 00:17:55,807
There was still
100 times too much lead.
266
00:17:55,841 --> 00:17:58,776
He had been at it
for more than two years.
267
00:17:58,811 --> 00:18:01,512
Duck soup, my ass.
268
00:18:08,987 --> 00:18:11,656
(bubbling)
269
00:18:11,690 --> 00:18:14,492
Patterson realized he would
have to boil his containers
270
00:18:14,494 --> 00:18:17,595
and tools in acid and purify
all his chemicals
271
00:18:17,629 --> 00:18:19,697
to further reduce
the lead in his lab.
272
00:18:19,731 --> 00:18:20,965
(door opens)
273
00:18:20,999 --> 00:18:22,467
Hey, you...
Oh, I...
274
00:18:22,501 --> 00:18:23,701
No!
I'm new here.
275
00:18:23,735 --> 00:18:24,936
Uh, where's the men's room?
276
00:18:24,970 --> 00:18:27,672
Ugh, damn it.
(groans)
277
00:18:27,706 --> 00:18:32,343
All of Patterson's obsessive
scouring and sterilizing
278
00:18:32,377 --> 00:18:34,879
had still not
solved the problem.
279
00:18:34,913 --> 00:18:38,049
He would need to design his own
lab and build it from scratch.
280
00:18:38,083 --> 00:18:41,419
The opportunity arose
when Harrison Brown moved
281
00:18:41,486 --> 00:18:44,555
to the California Institute
of Technology in Pasadena
282
00:18:44,590 --> 00:18:47,692
and invited Patterson
to join him.
283
00:19:00,372 --> 00:19:01,806
Okay, Tom, that's enough.
284
00:19:01,840 --> 00:19:04,542
We can move through
the interlock, now.
285
00:19:04,576 --> 00:19:08,179
Patterson had now
been at it for six years,
286
00:19:08,213 --> 00:19:10,047
doggedly tracking down
and eliminating
287
00:19:10,082 --> 00:19:11,549
the many sources of lead
288
00:19:11,583 --> 00:19:14,018
that were compromising
his instruments.
289
00:19:14,052 --> 00:19:18,189
He had built the world's
first ultra-clean room.
290
00:19:18,223 --> 00:19:20,525
He was finally able
to measure how much lead
291
00:19:20,559 --> 00:19:22,527
was actually in the rock.
292
00:19:22,561 --> 00:19:25,363
One whose age
had already been established.
293
00:19:25,397 --> 00:19:28,766
Now, at last,
Patterson was ready
294
00:19:28,800 --> 00:19:31,469
to tackle the iron meteorite,
295
00:19:31,503 --> 00:19:36,374
to find the true age
of the Earth.
296
00:19:36,408 --> 00:19:38,175
He brought
his meteorite specimen
297
00:19:38,210 --> 00:19:41,746
back to the Argonne
National Laboratory...
298
00:19:41,780 --> 00:19:44,448
where the world's most
accurate mass spectrometer
299
00:19:44,550 --> 00:19:46,450
had just become operational.
300
00:19:49,321 --> 00:19:52,039
Doc, this can't wait
till tomorrow?
301
00:20:09,007 --> 00:20:13,578
Okay, little buddy, we're
gonna have to vaporize you.
302
00:20:14,813 --> 00:20:16,581
(electric whirring)
303
00:20:23,421 --> 00:20:26,924
DEGRASSE TYSON:
A mass spectrometer
uses magnets
304
00:20:26,926 --> 00:20:29,293
to separate the elements
contained in a sample,
305
00:20:29,328 --> 00:20:32,597
so that the amounts of each
element can be quantified.
306
00:20:32,631 --> 00:20:35,299
This would provide
the last missing piece
307
00:20:35,334 --> 00:20:37,802
in the puzzle
of the Earth's true age.
308
00:20:42,040 --> 00:20:45,776
PATTERSON:
Now I'm gonna ionize you, yeah.
309
00:20:45,811 --> 00:20:47,945
Sounds worse than it is.
310
00:20:47,980 --> 00:20:50,314
What's an electron
between friends?
311
00:20:50,349 --> 00:20:55,486
DEGRASSE TYSON:
Having isolated the sample from
any outside lead contamination,
312
00:20:55,520 --> 00:20:58,906
Patterson was, at last,
ready to measure the amount
313
00:20:58,957 --> 00:21:01,626
of lead and uranium
in the sample
314
00:21:01,660 --> 00:21:05,696
and calculate how many years
before it had formed.
315
00:21:05,731 --> 00:21:08,265
The true age of the Earth.
316
00:21:08,300 --> 00:21:13,604
PATTERSON:
Thank you to all the scientists
who came before.
317
00:21:13,639 --> 00:21:17,375
Thank you, geologists.
318
00:21:17,409 --> 00:21:20,878
Thank you, Charles Lyell.
319
00:21:23,181 --> 00:21:25,549
Thank you, Michael Faraday.
320
00:21:32,357 --> 00:21:34,725
J.J. Thomson.
321
00:21:40,699 --> 00:21:42,867
Ernest Rutherford.
322
00:21:51,276 --> 00:21:55,012
Thank you, Harrison Brown.
323
00:22:00,752 --> 00:22:06,590
The world is four
and a half billion years old.
324
00:22:06,592 --> 00:22:10,094
We did it.
325
00:22:20,572 --> 00:22:22,506
Mom?
326
00:22:22,541 --> 00:22:24,341
Mom.
327
00:22:24,376 --> 00:22:26,043
DEGRASSE TYSON:
Patterson wanted
his mother to be
328
00:22:26,078 --> 00:22:27,912
the first person to know
what he had struggled
329
00:22:27,946 --> 00:22:30,915
for so many years to discover--
330
00:22:30,949 --> 00:22:33,451
the true age of the Earth.
331
00:22:36,822 --> 00:22:38,756
His reward for this discovery?
332
00:22:38,790 --> 00:22:40,858
A world of trouble.
333
00:22:40,892 --> 00:22:44,528
He didn't know it, but he was
on a collision course
334
00:22:44,563 --> 00:22:48,599
with some of the most powerful
people on the planet.
335
00:23:05,467 --> 00:23:07,902
(whooshing)
336
00:23:12,941 --> 00:23:15,309
DEGRASSE TYSON:
To the ancient Romans,
337
00:23:15,343 --> 00:23:18,312
the majestic ringed planet
Saturn was not a real place,
338
00:23:18,346 --> 00:23:21,148
not a world, but a god-king,
339
00:23:21,183 --> 00:23:24,151
a son of the marriage
of Heaven and Earth,
340
00:23:24,186 --> 00:23:28,456
the God of Lead.
341
00:23:28,523 --> 00:23:31,826
These columns are
all that remain
342
00:23:31,860 --> 00:23:34,261
of this oldest temple
in the Roman Forum,
343
00:23:34,296 --> 00:23:37,832
first consecrated to Saturn
2,500 years ago.
344
00:23:37,866 --> 00:23:40,501
It also served
as Rome's treasury
345
00:23:40,535 --> 00:23:43,003
and its bureau of weights
and measures.
346
00:23:45,440 --> 00:23:48,442
Tonight is Saturnalia,
347
00:23:48,477 --> 00:23:50,845
the wild December holiday
in Saturn's honor.
348
00:23:50,879 --> 00:23:53,280
And everyday life
will be turned upside down.
349
00:23:53,315 --> 00:23:55,616
The masters will serve
the slaves,
350
00:23:55,650 --> 00:23:58,085
no wars or executions
will be allowed,
351
00:23:58,120 --> 00:23:59,987
and gifts will be exchanged.
352
00:24:00,021 --> 00:24:01,689
A couple of hundred years
from now,
353
00:24:01,723 --> 00:24:03,924
when the early church fathers
look for a way
354
00:24:03,926 --> 00:24:05,626
to attract more pagans,
355
00:24:05,660 --> 00:24:08,662
they'll decide to turn
Saturnalia into Christmas,
356
00:24:08,697 --> 00:24:10,698
making it the latest
in a long line
357
00:24:10,732 --> 00:24:12,800
of winter solstice holidays
to be repurposed.
358
00:24:20,842 --> 00:24:24,512
This towering wooden statue
of Saturn was dressed
359
00:24:24,546 --> 00:24:28,349
in red woolen underwear
on only one night of the year.
360
00:24:28,383 --> 00:24:33,220
But in ancient Rome, this god
had another, darker side.
361
00:24:33,255 --> 00:24:38,325
That other Saturn is a cold
and sullen, sluggish ghoul,
362
00:24:38,360 --> 00:24:41,395
given to irrational bouts
of rage.
363
00:24:41,429 --> 00:24:45,499
He committed an unspeakable act
of violence against his father,
364
00:24:45,534 --> 00:24:48,035
and devoured his own children.
365
00:24:48,069 --> 00:24:49,904
Of all the planets visible
366
00:24:49,938 --> 00:24:52,239
to the unaided eyes
of the ancients,
367
00:24:52,274 --> 00:24:54,708
Saturn is the slowest,
368
00:24:54,743 --> 00:24:56,911
which could explain
why it's named
369
00:24:56,945 --> 00:24:58,946
after the God of Lead.
370
00:25:01,583 --> 00:25:03,250
But there's no denying
371
00:25:03,285 --> 00:25:05,553
that the more negative aspects
of Saturn's personality
372
00:25:05,587 --> 00:25:09,557
reflect the age-old knowledge of
the symptoms of lead poisoning.
373
00:25:09,591 --> 00:25:11,058
Funny thing about the Romans.
374
00:25:11,092 --> 00:25:12,693
Even though they knew
375
00:25:12,727 --> 00:25:15,196
that contact with lead
inevitably poisoned people,
376
00:25:15,230 --> 00:25:17,598
rendered them sterile
and drove them mad,
377
00:25:17,632 --> 00:25:19,767
what metal did they use
to make the pipes
378
00:25:19,801 --> 00:25:22,336
that carried the water through
their legendary aqueducts?
379
00:25:22,370 --> 00:25:24,338
I'll give you a hint.
380
00:25:24,372 --> 00:25:26,140
The word "plumbing" comes
381
00:25:26,174 --> 00:25:30,077
from the Latin word for lead,
"plumbum."
382
00:25:40,989 --> 00:25:44,558
What metal did they use
to line their famous baths?
383
00:25:44,593 --> 00:25:48,562
And how did they sweeten their
wines when they were too sour?
384
00:25:48,597 --> 00:25:52,099
What did they use to line
their vats and cooking pots?
385
00:25:52,133 --> 00:25:54,235
There are some historians
who believe
386
00:25:54,269 --> 00:25:57,605
that the widespread use of lead
was a major cause
387
00:25:57,639 --> 00:26:00,407
in the decline and fall
of the Roman Empire.
388
00:26:00,442 --> 00:26:02,810
Why did they continue
to use lead
389
00:26:02,844 --> 00:26:05,079
long after they knew
it was toxic?
390
00:26:06,681 --> 00:26:11,085
It was cheap, very malleable,
easy to work with,
391
00:26:11,119 --> 00:26:14,154
and the ones who were exposed to
it at its most lethal levels--
392
00:26:14,189 --> 00:26:16,557
the miners and workers
who processed the lead--
393
00:26:16,559 --> 00:26:18,592
were considered expendable.
394
00:26:18,627 --> 00:26:20,594
Their lives didn't matter.
395
00:26:20,629 --> 00:26:22,463
They were slaves.
396
00:26:22,497 --> 00:26:25,432
Most of the Earth's lead
started off at a safe distance
397
00:26:25,467 --> 00:26:28,068
from living things,
down below the surface,
398
00:26:28,103 --> 00:26:30,437
but about 8,500 years ago,
399
00:26:30,472 --> 00:26:33,574
humans began figuring out
how to dig into the Earth
400
00:26:33,641 --> 00:26:35,175
and extract metals from rock.
401
00:26:35,210 --> 00:26:37,344
By the time this villa was new,
402
00:26:37,379 --> 00:26:39,647
just a couple
of thousand years ago,
403
00:26:39,681 --> 00:26:44,084
the Romans were producing
80,000 tons of lead a year.
404
00:26:44,119 --> 00:26:48,922
Why is lead so poisonous to us?
405
00:26:48,957 --> 00:26:51,592
Because when it gets
into our bodies,
406
00:26:51,626 --> 00:26:55,296
lead mimics other metals,
like zinc and iron,
407
00:26:55,330 --> 00:26:59,199
the ones our cells actually
need to grow and flourish.
408
00:27:01,903 --> 00:27:04,938
Enzymes in the cell are fooled
by the lead's masquerade,
409
00:27:04,973 --> 00:27:07,274
and they begin to dance.
410
00:27:07,309 --> 00:27:10,811
But it's a dance of death,
because the lead is an imposter
411
00:27:10,813 --> 00:27:13,547
that can't fulfill
the cell's vital needs.
412
00:27:13,581 --> 00:27:17,217
Lead also blocks
neurotransmitters,
413
00:27:17,252 --> 00:27:20,220
the communication network
between the cells.
414
00:27:22,424 --> 00:27:24,858
It interferes
with the molecular receptors
415
00:27:24,893 --> 00:27:26,994
that are vital
to memory and learning.
416
00:27:27,028 --> 00:27:29,963
This is especially damaging
to children,
417
00:27:29,998 --> 00:27:33,534
but lead poisoning
spares no one.
418
00:27:33,568 --> 00:27:36,904
Starting at the turn
of the 20th century,
419
00:27:36,938 --> 00:27:39,640
the makers of leaded paint
hired the fledgling
420
00:27:39,674 --> 00:27:42,509
advertising industry
to persuade the consumer
421
00:27:42,544 --> 00:27:45,045
that lead was child-friendly.
422
00:27:45,080 --> 00:27:48,215
MAN:
A little toy lead soldier
once to the Dutch Boy said,
423
00:27:48,249 --> 00:27:51,218
"We have some fine relations
who all contain some lead.
424
00:27:51,252 --> 00:27:54,421
"Why don't you give a party
so folks can meet and see
425
00:27:54,456 --> 00:27:57,157
the other happy members
of the great lead family?"
426
00:27:57,192 --> 00:27:59,993
The first one at the party
was Gay Electric Light.
427
00:28:00,028 --> 00:28:01,829
He said, "I'm very brilliant.
428
00:28:01,863 --> 00:28:03,664
"I always shine at night.
429
00:28:03,698 --> 00:28:06,734
"No little of my brilliance
is due to my glass head,
430
00:28:06,768 --> 00:28:08,268
"which gives a light
much brighter
431
00:28:08,303 --> 00:28:10,337
because it's made with lead."
432
00:28:10,372 --> 00:28:13,374
A pair or rubbers entered
and took the Dutch Boy's arm.
433
00:28:13,408 --> 00:28:17,077
They said, "We are protectors
who keep you dry and warm.
434
00:28:17,112 --> 00:28:20,013
"You knew when we were molded,
the man who made us said,
435
00:28:20,048 --> 00:28:21,749
"we're strong
and tough and lively
436
00:28:21,783 --> 00:28:24,184
because in us, there's lead."
437
00:28:24,219 --> 00:28:27,354
DEGRASSE TYSON:
But lead production didn't
really shift into high gear
438
00:28:27,389 --> 00:28:29,590
until the early 1920s
439
00:28:29,624 --> 00:28:31,959
when chemist Thomas Midgley
and inventor
440
00:28:31,993 --> 00:28:34,027
Charles Kettering
of General Motors
441
00:28:34,062 --> 00:28:36,764
found that tetraethyl lead
could be marketed
442
00:28:36,798 --> 00:28:40,467
as an anti-knock additive
to gasoline.
443
00:28:42,437 --> 00:28:46,056
They formed a new company
called the Ethyl Corporation.
444
00:28:46,107 --> 00:28:48,876
It had once been considered
for use
445
00:28:48,910 --> 00:28:52,312
as a poison gas
by the U.S. War Department.
446
00:28:52,347 --> 00:28:56,150
Unlike the lead in paint,
tetraethyl lead was fat soluble.
447
00:28:56,184 --> 00:28:59,286
A half a cup of it
on your skin could kill you.
448
00:28:59,320 --> 00:29:01,388
The manufacturers calculated
449
00:29:01,423 --> 00:29:04,391
that they could sell
60 million tons of it a year.
450
00:29:04,426 --> 00:29:06,660
Only problem was,
451
00:29:06,694 --> 00:29:08,796
some of the workers
who processed the stuff
452
00:29:08,830 --> 00:29:13,584
in factories in Delaware and
New Jersey were going insane,
453
00:29:13,635 --> 00:29:17,337
hallucinating,
jumping out of windows.
454
00:29:17,372 --> 00:29:19,239
They died screaming.
455
00:29:19,274 --> 00:29:21,074
(screaming)
456
00:29:21,109 --> 00:29:23,977
This was a selling job
that would require a lot more
457
00:29:23,995 --> 00:29:25,479
than dancing light bulbs.
458
00:29:25,513 --> 00:29:29,082
(laughing)
459
00:29:29,117 --> 00:29:32,152
(cackling)
460
00:29:32,187 --> 00:29:36,290
What was needed was a man
of science
461
00:29:36,324 --> 00:29:40,294
to calm the public's fears
and improve lead's image.
462
00:29:40,328 --> 00:29:43,430
They found the right man
for the job.
463
00:29:43,465 --> 00:29:45,966
This was one of the first times
464
00:29:46,000 --> 00:29:48,135
that the authority
of science was used
465
00:29:48,169 --> 00:29:51,171
to cloak a threat to public
health and the environment.
466
00:29:51,206 --> 00:29:54,341
Robert Kehoe,
a young doctor from Cincinnati,
467
00:29:54,375 --> 00:29:56,343
was hired by GM.
468
00:29:56,377 --> 00:29:59,213
He raised scientific doubts
in the public mind
469
00:29:59,247 --> 00:30:02,032
about the dangers of lead.
470
00:30:02,083 --> 00:30:05,452
Lead was naturally occurring
in the environment, he said.
471
00:30:05,553 --> 00:30:07,955
Yes, there might be
occupational hazards
472
00:30:07,989 --> 00:30:10,858
for the people
who worked with lead, but
473
00:30:10,892 --> 00:30:14,528
that could be best handled
by industry self-regulation.
474
00:30:14,562 --> 00:30:16,797
And there was no evidence
to suggest
475
00:30:16,831 --> 00:30:20,033
that lead posed any threat
to the consumer.
476
00:30:20,068 --> 00:30:23,971
For decades
no one challenged him...
477
00:30:24,005 --> 00:30:28,041
until Clair Patterson
went searching
478
00:30:28,076 --> 00:30:31,445
for the age of the Earth.
479
00:30:33,698 --> 00:30:36,166
on the age of the Earth
480
00:30:36,201 --> 00:30:37,968
had made him
the world's leading expert
481
00:30:38,002 --> 00:30:39,770
on measuring trace amounts
of lead.
482
00:30:39,804 --> 00:30:41,705
And like everyone else
at the time,
483
00:30:41,739 --> 00:30:44,942
he assumed the prevalence
of lead occurred naturally.
484
00:30:44,976 --> 00:30:47,945
(thunder cracks)
485
00:30:48,012 --> 00:30:51,215
True scientist that he was,
he set out
486
00:30:51,249 --> 00:30:53,016
to discover everything he could
487
00:30:53,051 --> 00:30:56,854
about how lead circulates
through the environment.
488
00:30:56,888 --> 00:30:59,256
On a grant from the American
Petroleum Institute,
489
00:30:59,290 --> 00:31:02,192
he carefully measured
the concentrations of lead
490
00:31:02,227 --> 00:31:04,261
in deep and shallow seawater.
491
00:31:04,295 --> 00:31:06,763
Once again, Patterson found
492
00:31:06,765 --> 00:31:08,899
that his initial data
made no sense.
493
00:31:08,933 --> 00:31:11,702
There were only minuscule
concentrations of lead
494
00:31:11,736 --> 00:31:13,370
in the deep ocean water.
495
00:31:13,404 --> 00:31:15,906
But in shallow waters
and at the surface,
496
00:31:15,940 --> 00:31:19,626
the concentrations of lead
were hundreds of times greater.
497
00:31:19,677 --> 00:31:22,112
In any ocean,
it takes a few hundred years
498
00:31:22,130 --> 00:31:24,147
for the shallow waters
to mix with the deep.
499
00:31:24,215 --> 00:31:27,150
This told Patterson
that the large amount of lead
500
00:31:27,252 --> 00:31:30,353
in the surface waters
had arrived recently.
501
00:31:30,355 --> 00:31:33,290
Otherwise it would have been
more evenly distributed.
502
00:31:33,357 --> 00:31:35,759
Knowing the quantity of lead
in the shallow seas
503
00:31:35,793 --> 00:31:38,729
and the time needed to mix it
into the deeper layers,
504
00:31:38,763 --> 00:31:41,765
he was able to estimate
the rate of lead contamination
505
00:31:41,799 --> 00:31:43,767
at the surface.
506
00:31:43,801 --> 00:31:46,637
Patterson asked himself
507
00:31:46,671 --> 00:31:49,706
what could possibly supply lead
to the world's oceans
508
00:31:49,741 --> 00:31:51,875
at such a rate.
509
00:31:53,511 --> 00:31:56,513
¶ ¶
510
00:32:04,022 --> 00:32:07,157
¶ ¶
511
00:32:11,829 --> 00:32:14,665
Where's all that lead
coming from?
512
00:32:14,682 --> 00:32:16,533
I think I know, Harrison.
513
00:32:16,567 --> 00:32:19,703
It's from leaded gasoline.
514
00:32:19,737 --> 00:32:22,606
Well, then we've got
a problem, Pat,
515
00:32:22,640 --> 00:32:26,843
because that's the same
place the money comes from.
516
00:32:26,878 --> 00:32:30,547
But Patterson
would not give in.
517
00:32:30,581 --> 00:32:33,617
He went right to work on
publishing the scientific paper
518
00:32:33,651 --> 00:32:37,554
that would make the case
against leaded gasoline.
519
00:32:37,588 --> 00:32:40,724
When he sent the paper to the
prestigious scientific journal
520
00:32:40,758 --> 00:32:43,727
Nature, Patterson put
his own name second.
521
00:32:43,761 --> 00:32:45,729
He often did that
with his students
522
00:32:45,763 --> 00:32:47,698
to advance their reputations.
523
00:32:47,732 --> 00:32:50,901
He made a lifelong point
of shunning the limelight
524
00:32:50,935 --> 00:32:53,236
and the privileges
that come with it.
525
00:32:56,274 --> 00:32:58,575
Only three days
after publication...
526
00:33:00,778 --> 00:33:03,246
...the push-back began.
527
00:33:12,757 --> 00:33:15,258
Hello, Dr. Patterson.
Pleasure to meet you.
528
00:33:15,293 --> 00:33:16,860
Very impressed
by your work.
529
00:33:16,894 --> 00:33:19,596
Your work is
of great interest
530
00:33:19,630 --> 00:33:22,766
to us in the petroleum
and chemical industries.
531
00:33:22,800 --> 00:33:25,936
Well, it wouldn't have been
possible without your funding.
532
00:33:25,970 --> 00:33:29,940
Precisely. And there's so much
more we'd like to do for you.
533
00:33:29,974 --> 00:33:33,944
Well, I've been thinking about
measuring lead in polar ice
534
00:33:33,978 --> 00:33:37,447
to see if it shows the same kind
of pattern as the oceans.
535
00:33:37,482 --> 00:33:40,117
Lead? But you've
already done that.
536
00:33:40,151 --> 00:33:44,121
We're thinking it's time you
move on to other trace elements.
537
00:33:44,155 --> 00:33:46,456
In fact,
Dr. Patterson,
538
00:33:46,491 --> 00:33:50,627
our ability to fund you in
any other line of research is...
539
00:33:50,661 --> 00:33:52,396
virtually limitless.
540
00:33:53,431 --> 00:33:56,133
Lead is a neurotoxin.
541
00:33:56,167 --> 00:33:59,870
When you ship your tetraethyl
lead from the factory--
542
00:33:59,887 --> 00:34:01,705
before you add it
to the gasoline--
543
00:34:01,806 --> 00:34:03,774
it's handled
just like a chemical weapon.
544
00:34:03,808 --> 00:34:05,242
There's a reason for that.
545
00:34:05,276 --> 00:34:07,778
Where do you suppose
all that lead goes
546
00:34:07,812 --> 00:34:10,247
after it leaves
the tailpipe?
547
00:34:10,281 --> 00:34:14,084
Think about what it might
be doing to us and our kids.
548
00:34:14,118 --> 00:34:17,721
Dr. Kehoe has shown
that the level of lead
549
00:34:17,755 --> 00:34:22,059
in the environment is
as natural as snow in December.
550
00:34:22,093 --> 00:34:25,796
(sighs) Then why doesn't it
show up in the deep water? Here,
551
00:34:25,830 --> 00:34:28,098
let me just show you.
552
00:34:28,132 --> 00:34:30,567
Thanks for your time.
553
00:34:30,601 --> 00:34:32,636
Wait, you're just
gonna keep on putting
554
00:34:32,670 --> 00:34:35,472
millions of tons of poison
into the air we breathe?
555
00:34:35,506 --> 00:34:38,809
If my research doesn't
put you out of business,
556
00:34:38,843 --> 00:34:40,543
some future
scientist will.
557
00:34:40,545 --> 00:34:43,080
Patterson's funding
from the oil industry
558
00:34:43,147 --> 00:34:44,648
vanished overnight.
559
00:34:44,682 --> 00:34:47,651
In fact, they tried
to get him fired.
560
00:34:47,685 --> 00:34:52,122
But the U.S. government--
the Army, the Navy,
561
00:34:52,156 --> 00:34:55,625
the Atomic Energy Commission,
the Public Health Service,
562
00:34:55,660 --> 00:34:58,829
and the National Science
Foundation-- stood by him,
563
00:34:58,863 --> 00:35:01,331
supporting his research
on lead pollution.
564
00:35:01,365 --> 00:35:05,469
His investigations took him
from Greenland in the far north
565
00:35:05,503 --> 00:35:07,471
to Antarctica in the far south,
566
00:35:07,505 --> 00:35:11,541
and to rivers, mountains
and valleys in between.
567
00:35:11,576 --> 00:35:14,010
(wind whistling)
568
00:35:14,045 --> 00:35:15,979
In even the most
hostile conditions,
569
00:35:16,080 --> 00:35:18,615
Patterson and his team
worked to replicate
570
00:35:18,649 --> 00:35:21,451
the immaculate environment
of the clean room.
571
00:35:21,486 --> 00:35:24,271
Their plastic suits
were replaced daily.
572
00:35:24,322 --> 00:35:28,125
Working ten- to 12-hour days
in subzero weather,
573
00:35:28,159 --> 00:35:30,293
they dug a 200-foot-long shaft
574
00:35:30,328 --> 00:35:32,829
into the ice of Antarctica.
575
00:35:32,864 --> 00:35:34,831
It was a form of time travel,
576
00:35:34,866 --> 00:35:38,034
to recover snow that
had fallen three centuries ago,
577
00:35:38,069 --> 00:35:41,204
before the start
of the Industrial Revolution.
578
00:35:42,240 --> 00:35:44,007
Nose!
579
00:35:44,041 --> 00:35:46,143
Wipe your nose, damn it!
580
00:35:46,145 --> 00:35:48,245
There's a thousand times
more lead in you
581
00:35:48,279 --> 00:35:49,679
than in this ice!
582
00:35:49,714 --> 00:35:52,716
You want to contaminate
the whole damn sample?!
583
00:35:56,420 --> 00:35:59,256
DEGRASSE TYSON:
After four grueling weeks
584
00:35:59,323 --> 00:36:01,258
of painstaking
sample collection,
585
00:36:01,292 --> 00:36:04,194
Patterson was ready
to go back to the lab.
586
00:36:04,228 --> 00:36:05,862
(wind whistling)
587
00:36:05,897 --> 00:36:09,766
As with the oceans,
he found that the amount of lead
588
00:36:09,800 --> 00:36:13,570
was much lower in the snow
of a few hundred years before.
589
00:36:13,604 --> 00:36:15,872
No matter where
he searched on Earth,
590
00:36:15,907 --> 00:36:18,708
no matter how far
he traveled back in time,
591
00:36:18,743 --> 00:36:21,678
the results always told
the same story:
592
00:36:21,712 --> 00:36:25,415
the naturally occurring levels
in the air and water in the past
593
00:36:25,449 --> 00:36:27,884
were far lower.
594
00:36:27,919 --> 00:36:31,755
¶ ¶
595
00:36:31,789 --> 00:36:34,558
For thousands of years,
lead had been known
596
00:36:34,592 --> 00:36:37,727
to cause brain damage,
developmental impairment,
597
00:36:37,762 --> 00:36:41,264
violent behavior,
and even death.
598
00:36:41,299 --> 00:36:43,266
In searching
for the age of the Earth,
599
00:36:43,301 --> 00:36:45,101
Patterson had stumbled
on the evidence
600
00:36:45,136 --> 00:36:48,972
for a mass poisoning
on an unprecedented scale.
601
00:36:52,944 --> 00:36:54,911
But Kehoe
and the other scientists
602
00:36:54,946 --> 00:36:57,113
employed by the lead industry
603
00:36:57,148 --> 00:37:01,051
persuaded the public they
had nothing to worry about.
604
00:37:01,085 --> 00:37:03,620
Everyone thought
Patterson was a crank
605
00:37:03,687 --> 00:37:07,290
until one man started
to pay attention.
606
00:37:10,912 --> 00:37:13,914
Patterson went public
with his discoveries
607
00:37:13,948 --> 00:37:15,582
about lead in a big way.
608
00:37:15,616 --> 00:37:17,017
He published his findings
609
00:37:17,051 --> 00:37:18,919
in a major
environmental health journal
610
00:37:18,953 --> 00:37:21,254
and sent copies
to various government leaders,
611
00:37:21,289 --> 00:37:24,925
including one
highly influential senator.
612
00:37:24,959 --> 00:37:27,294
(gavel banging)
613
00:37:29,330 --> 00:37:32,599
Edmund Muskie of Maine
was the chairman
614
00:37:32,633 --> 00:37:36,036
of the Senate Subcommittee
on Air and Water Pollution.
615
00:37:36,070 --> 00:37:40,106
In 1966 he held hearings
on the lead question.
616
00:37:40,141 --> 00:37:42,042
The first witness
617
00:37:42,076 --> 00:37:45,946
was Dr. Robert Kehoe,
longtime scientific advocate
618
00:37:45,980 --> 00:37:48,081
for leaded gasoline.
619
00:37:48,115 --> 00:37:51,284
Is it, uh, your conclusion
that, in 1937
620
00:37:51,319 --> 00:37:53,653
to the present time,
there has been
621
00:37:53,688 --> 00:37:56,122
no increase
in the amount of lead
622
00:37:56,157 --> 00:37:59,993
taken in from the atmosphere by
the average traffic policeman,
623
00:38:00,027 --> 00:38:03,363
service station attendant,
or... or motorist?
624
00:38:03,397 --> 00:38:05,298
There is not
the slightest evidence
625
00:38:05,300 --> 00:38:07,934
that there has been a change
in this picture
626
00:38:07,969 --> 00:38:09,936
during this period of time.
627
00:38:09,971 --> 00:38:12,272
Not the slightest.
628
00:38:12,306 --> 00:38:14,507
DEGRASSE TYSON:
The hearings were scheduled
to take place
629
00:38:14,525 --> 00:38:17,277
when their fiercest critic,
Clair Patterson,
630
00:38:17,344 --> 00:38:20,013
was off in Antarctica.
631
00:38:20,047 --> 00:38:22,082
But he unexpectedly appeared
632
00:38:22,116 --> 00:38:25,652
on the fifth day of testimony.
633
00:38:25,686 --> 00:38:27,854
Uh, looks like there
seems to be an increase
634
00:38:27,888 --> 00:38:30,857
in the concentration
of lead in people
635
00:38:30,891 --> 00:38:33,293
as a result of exposure
to the environment.
636
00:38:33,327 --> 00:38:34,995
Is that correct?
637
00:38:35,029 --> 00:38:36,796
That is correct.
638
00:38:36,831 --> 00:38:39,466
In identifying
typical lead levels,
639
00:38:39,500 --> 00:38:44,037
you use actual measurements
you've taken in the field?
640
00:38:44,071 --> 00:38:45,505
Yes.
641
00:38:45,539 --> 00:38:48,041
A-Are these
observations different
642
00:38:48,075 --> 00:38:51,511
from the ones we've been hearing
about from other witnesses?
643
00:38:51,545 --> 00:38:55,515
No, th-they're
the same observations.
644
00:38:55,549 --> 00:38:58,684
You-You've testified
that there has been
645
00:38:58,686 --> 00:39:01,654
no change in natural
lead levels, is that correct?
646
00:39:01,689 --> 00:39:02,889
That is correct.
647
00:39:02,923 --> 00:39:04,624
You're sure about that?
648
00:39:04,658 --> 00:39:06,292
Absolutely.
649
00:39:06,327 --> 00:39:09,162
The levels we see
in people today may be typical.
650
00:39:09,196 --> 00:39:11,698
(chuckling):
But they are not
by any means natural.
651
00:39:11,732 --> 00:39:15,368
So you don't disagree
with Dr. Kehoe's numbers?
652
00:39:15,403 --> 00:39:16,870
Uh, no, no.
653
00:39:16,887 --> 00:39:18,838
You're saying that
the same numbers
654
00:39:18,873 --> 00:39:21,374
are leading to
different conclusions?
655
00:39:21,409 --> 00:39:22,842
Yes.
656
00:39:22,877 --> 00:39:25,345
You know, this is
the kind of thing
657
00:39:25,379 --> 00:39:29,682
we expect to hear from
lawyers, not scientists.
658
00:39:29,717 --> 00:39:31,317
(people laughing)
659
00:39:31,352 --> 00:39:34,054
I would agree with that, yes.
660
00:39:34,088 --> 00:39:37,524
You seem to be very sure
of your conclusions, Dr. Kehoe.
661
00:39:37,558 --> 00:39:41,061
It so happens that I have
more experience in this field
662
00:39:41,095 --> 00:39:43,263
than anyone else alive.
663
00:39:43,297 --> 00:39:47,734
At these levels, lead
is a severe chronic insult
664
00:39:47,768 --> 00:39:49,669
to the human body.
665
00:39:49,703 --> 00:39:52,672
There is no medical evidence
that lead has introduced
666
00:39:52,706 --> 00:39:55,008
a danger to public health.
667
00:39:55,042 --> 00:39:58,511
It's irresponsible
to mine millions of tons
668
00:39:58,546 --> 00:40:01,648
of toxic material and disperse
it into the environment!
669
00:40:01,749 --> 00:40:05,018
If there was proof of harm,
we would have found it.
670
00:40:05,052 --> 00:40:07,420
Not if your purpose
is to sell lead.
671
00:40:07,455 --> 00:40:11,925
DEGRASSE TYSON:
Patterson fought the industry
for another 20 years
672
00:40:11,959 --> 00:40:15,795
before lead was finally banned
in U.S. consumer products.
673
00:40:15,830 --> 00:40:18,264
The man who figured out
the age of the Earth
674
00:40:18,299 --> 00:40:20,266
was also responsible for one
675
00:40:20,301 --> 00:40:24,104
of the greatest public health
victories of the 20th century.
676
00:40:24,138 --> 00:40:27,340
In just a few years,
average lead levels
677
00:40:27,342 --> 00:40:31,144
in the blood of children
plummeted by some 75%.
678
00:40:31,146 --> 00:40:34,314
Today, the medical consensus
is unanimous--
679
00:40:34,316 --> 00:40:37,350
there's no such thing
as a nontoxic level
680
00:40:37,352 --> 00:40:40,653
of lead in humans,
however small.
681
00:40:40,655 --> 00:40:42,288
Today, scientists
sound the alarm
682
00:40:42,290 --> 00:40:44,491
on other environmental dangers.
683
00:40:44,493 --> 00:40:46,793
Vested interests still hire
their own scientists
684
00:40:46,795 --> 00:40:48,828
to confuse the issue.
685
00:40:48,830 --> 00:40:50,796
But in the end,
686
00:40:50,798 --> 00:40:53,533
nature will not be fooled.
687
00:40:53,535 --> 00:40:55,935
¶ ¶
688
00:41:02,676 --> 00:40:55,935
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