Kind: captions
Language: en
one single scientist created three
inventions that accidentally caused the
deaths of millions of people including
himself not only that they decreased the
average intelligence of people all
around the world increased crime rates
and caused two completely separate
environmental disasters that we are
still dealing with
Today part of this video is sponsored by
Ren more about them at the end of the
show
in 1944 as a young chemist who had just
finished his Masters Claire Patterson
went to work on the Manhattan Project
building the first nuclear weapons his
job was to concentrate uranium 235 the
fizo fuel for bombs from the much more
common uranium 238 and this required
huge machines Mass spectrometers which
separated the two types of uranium by
their slight difference in Mass
after the war Patterson went back to
grad school to get his PhD he picked a
research project that would take
advantage of his experience with mass
spectrometers measuring the age of the
Earth radioactive rocks are effectively
clocks uranium 238 for example decays
into thorium and then protactinium and
then 12 more decays until it ends up as
lead 206 which is stable the rate of
this Decay is consistent and can be
measured it takes 42 billion years for
half of a sample of u238 to Decay into
lead
206 Patterson's PhD project was to
determine the age of the Earth by
measuring the ratio of uranium to lead
in primordial rocks but to calibrate his
instrument first he used ziron crystals
whose Ages were known ziron is ideal for
this purpose because when it forms it
contains Trace Amounts of uranium but
absolutely no lead so any lead that you
later find inside a ziron you know must
be the product of a uranium Decay now
Patterson was tasked with measuring the
lead content and another student George
Tilton measured
uranium Tilton's uranium measurements
were fine they matched predictions but
Patterson's lead measurements were all
over the place and they were many many
times higher than they expected we take
George's uranium and my lead not right
Patterson there was lead there that
didn't belong
there so where was all this extra lead
coming from that mystery would take over
the rest of Clare Patterson's life and
bring him to the literal ends of the
Earth in 1908 a woman was driving across
the Bell Isle bridge in Detroit when her
car car stalled a passing motorist
stopped to help in those days cars
needed to be hand cranked to start he
knelt down and turned the crank and the
engine roared to life a little too
suddenly the man couldn't get out of the
way the crank handle hit him in the face
and broke his
jaw he died as a result of his injuries
his name was Byron Carter and he was the
founder of his own car company so he was
well connected in the Detroit autoc
scene he counted among his close friends
the founder of Cadillac Henry Leland
Leland was so distraught over his
friend's death that he resolved to
eliminate hand cranks from his Vehicles
Leland hired Charles karing to create a
self-starting car and by 1911 he had a
working prototype hand cranking was
difficult and dangerous and best left to
men but a car that started itself
changed everything the world's first
crankers car was the Cadillac Model 30
it was much more powerful than cars
before it it had a top speed of 45 mph
and 40 horsepower double the Ford Model
T the model 30 was a huge success for
Cadillac doubling the company's annual
sales but it had a problem it was
deafeningly
loud in internal combustion engines a
piston compresses the fuel air mixture
which is then ignited by a spark from
the spark plug the expanding hot gases
push the Piston back down the problem
with the model 30 engine was it
compressed the fuel air mixture more
than previous models so much in fact
that often the fuel would spontaneously
combust before the spark from the spark
plug so rather than orderly perfectly
timed explosions you'd get multiple
halfhazard combustions leading to
turbulent pressure waves inside the
cylinder the resulting sound led the
problem to become known as engine
knocking knocking wasn't just hard on
the ears it hurt the engine's
performance it reduced power output and
lowered fuel efficiency the vibrations
also damaged the piston and walls of the
cylinder shortening the life of the
engine the good news was that engine
knocking could be corrected by changing
the fuel different fuels can withstand
different levels of compression before
detonating and heane for example will
spontaneous ly combust under only a
little compression ISO Octane on the
other hand can withstand a much higher
compression ratio before it auto ignites
so it's much less likely to cause
knocking to quantify how much
compression a fuel can withstand
scientists came up with the octane
rating system they arbitrarily set ISO
octane to have a rating of 100 and nane
a rating of zero now real fuels aren't
made up of only these two ingredients
they're a mix of lots of different
hydrocarbons but the the octane rating
tells you what mixture of octane and
heptane gives equivalent performance for
example 98 octane fuel can understand
the same compression as a mixture of 98%
Octane and 2% heptane now I'm going to
take a little bit of 98 octane fuel and
put it in this piston and when I
compress
it nothing happens which is exactly what
you'd expect this fuel can withstand a
lot of compression diesel has an OCT
rating of 20 so it acts like a mixture
of 20% isooctane and 80% and heane if I
put a little bit of diesel in there
let's see what happens with the same
compression
ratio there you go you get a little
explosion in there that's because this
is a low octane fuel I mean that's what
diesel is meant to do you compress it
and it ignites but you don't want this
sort of fuel in an engine with spark
plugs the reason fancy cars demand high
octane fuel is to prevent knocking in
their high compression high performance
engines karing wanted to find an
additive which would increase the octane
rating of ordinary Fuel and eliminate
knocking in high compression engines so
he hired 27-year-old engineer Thomas
Midgley Jr Midgley experimented with all
sorts of compounds from melted butter
and cam for to ethylacetate and aluminum
chloride he later wrote most most of
them had no more effect than spitting in
the Great
Lakes ethanol was an interesting
exception it did stop the knocking but
you needed a lot of it about 10% of the
fuel mixture for it to be effective that
much ethanol would be expensive and hard
to turn a profit on and mle was really
after an additive that was cheap easy to
produce and effective even at low
concentrations so he kept trying then he
hit on tum it worked wonderfully as an
anti agent but it had a terrible smell
you couldn't get rid of it by changing
clothes or bathing his wife was so
offended by the stench that he had to
sleep in the basement for 7 months mgy
wrote I don't think that although this
doubled the fuel economy Humanity would
suffer this
smell on December 3rd 1921 after 5 years
of working on the problem Midgley found
what he thought was the perfect solution
tetraethyl lead that's a lead atom right
there in the center this additive was
exactly what he was looking for it
stopped the knocking it didn't smell it
was cheap to produce and readily
available best of all you only needed
one part in a thousand for it to be
effective in a call to ketering Midgley
said can you imagine how much money
we're going to make with this we're
going to make $200 million maybe even
more that is over 3 billion in today's
dollar now for his Discovery the
American Chemical Society gave him the
prestigious Nichols award and they asked
him to do a series of public talks but
midgely declined he and kering patented
the process for making tetraethyl and
they called their new additive ethyl
perhaps so it might be confused with
another common additive ethyl alcohol
they made no mention of lead then they
teamed up with three of America's
largest corporations General Ms Dupont
and standard oil of New Jersey to form
the Ethel
Corporation their marketing was
brilliant no man can look at the amazing
record of accomplishment here in this
research division without confidence
that these men are going ahead with an
eye to the Future looking for new facts
and principles which will make things
better and make life easier for all of
us
[Music]
[Applause]
[Music]
at the 1923 Indianapolis 500 the top
three finishers all used Ethel and the
demand for Leed gasoline took off to
keep up ethyl Corporation had to build a
new chemical plant in New Jersey but the
project began terribly within 2 months
of operating dozens of workers fell ill
with lead poisoning five of them
died to address the public outcry midley
held a press conference and there he
poured tetraethyl lead onto his hands
and he inhaled it for a full minute he
claimed he could do this daily without
harm but mgle knew the dangers the
reason he had turned down the public
talks was because he spent much of 1923
in Florida where he himself was
recovering from lead poisoning he didn't
go anywhere near his company's product
if he could help it
lead is dangerous even in small doses it
mimics calcium in our bodies so there's
no efficient way to get rid of it and
like calcium lead can be stored in bones
for years meaning it can continue to
poison the body long after the initial
exposure the organ most sensitive to
lead is the brain lead breaks down the
myin sheath around axons and prevents
the release of neurotransmitters that's
why common symptoms of lead poisoning
are headaches memory loss and tingling
in the hands and feet and children are
particularly susceptible lead exposure
can cause permanent learning disorders
and behavioral problems and the dangers
of lead had been known for hundreds of
years already in 1786 Benjamin Franklin
remarked that lead had been used for far
too long considering its known toxicity
you will observe with concern how long a
useful truth may be known and exist
before it is generally received and
practiced on he would have been a g
asked to learn that nearly 150 years
later scientists plan to add lead to
fuel doctors and public health officials
from Mi Harvard Yale and the US Health
Service wrote to midley and warned them
against producing tetraethyl lead they
called lead a creeping and malicious
poison and a serious menace to Public
Health their concerns were
dismissed this model shows how just the
right amount of fluid containing
tetraethyl lead and dye is added to the
gasoline no one doubted that a lot of
lead was bad for you but how much harm
could a little lead
do by the 1950s millions of motorists
globally were burning lead in their cars
and releasing it into the air some of
that lead ended up on Clare Patterson's
ziron samples preventing him from
determining their age in 1952 he moved
to Caltech where he built a new lab from
scratch susp icious of environmental
contamination he tore the electrical
cables out of the walls to remove the
lead solder he cleaned the floors and
benches daily with ammonia and made sure
that air was always being blown out of
the lab to go inside you had to wear a
plastic bunny suit Patterson basically
invented the clean room inside that room
he turned his attention to the oldest
rocks in the solar system meteorites all
the original rocks on Earth had long
since been destroyed by tectonic
activity but meteorites come from
asteroids which formed around the same
time as Earth they have just been
drifting through space until they
entered the Earth's atmosphere so the
best way to measure the age of the Earth
was to measure the age of meteorites
Patterson measured five meteorites each
with three different radiometric dating
techniques and he found they were all
4.55 billion years old that number is
within
0.15% of the currently accepted value
for the age of the Earth you know before
Patterson's experiment people thought
the Earth was a billion years younger so
Patterson had done it he measured the
age of the Earth but he wasn't done
getting rid of lead
contaminants public concern about lead
exposure had continued to grow but
president of Standard Oil Frank Howard
pushed back saying we do not feel
justified in giving up what has come to
the industry like a gift from Heaven on
the possibility that a hazard may be
involved in
it scientists funded by the Ethel
Corporation claimed that lead was a
natural part of our environment and
therefore not harmful to people but
Patterson wondered just how natural is
the lead in our environment and he had
just the skills to find
out he began by measuring measuring lead
in the oceans if it were natural he
expected the concentration of lead to be
the same regardless of depth but if lead
pollution had increased recently it
would be more concentrated near the
surface he took samples in the Pacific
and Atlantic Oceans down to a depth of 4
km and sure enough lead concentrations
were nearly 10 times higher near the
surface lead pollution was clearly
recent but when exactly had it
occurred to find out out Patterson had
to go to Greenland and Antarctica ice
cores record the level of lead in the
air going back thousands of years the
levels of lead in the atmosphere have
been elevated for the last 4,500 years
all of it is due to human activity
mainly smelting ores to make metal you
can see the rise and fall of the Greek
and Roman Empires the dip caused by the
Black Death in the 1300s and of course
the spike in the 20th century due to
indust rization and tetraethyl
Lead so what did this do to people well
Patterson looked at the lead levels in
the teeth and bones of recently deceased
Americans and for comparison he measured
the lead in bones and teeth of Peruvian
and Egyptian mummies since they lived
over 1600 years ago they would have been
exposed to much less lead in their
lifetimes he expected to find modern
Americans had about a 100 times as much
lead in their bones but results showed
it was closer to a factor of a thousand
20th century Americans had a thousand
times more lead in their bones than
their
ancestors studies of baby teeth revealed
that even lead exposure well below the
level considered safe resulted in
delayed learning decreased IQ and
increased behavioral problems and
there's a a broad consensus on the part
of everybody except the lead industry
and its spokesman that lead is extremely
toxic at extremely low doses a follow-up
study showed that those with higher
levels of lead in their baby teeth were
many times more likely to fail out of
high school as a result of studies like
these the cdc's guidelines for the
acceptable level of lead in children's
blood dropped from 60 micrograms per
deciliter down to
3.5 and as far as we know today there is
no safe level of lead globally lead is
believed to be responsible for nearly
2/3 of all unexplained intellectual
disability according to a study
published in 2022 more than half of the
current US population that's 17 million
people were exposed to high levels of
lead in early childhood those born
between 1951 and 1980 are
disproportionately affected the authors
estimate that in aggregate lead caused a
loss of more than 800 million IQ points
the world is less intelligent today
because of leaded
gasoline but there are even more
troubling
correlations the US saw a steady rise in
crime from the 1970s to the
1990s then it abruptly declined this
graph looks eily similar to a plot of
preschool blood Le levels just offset by
20 years the obvious question is did
kids who were exposed to higher levels
of LED grow up to commit more crimes
than they otherwise would have you might
think this is just a spous correlation
but the same pattern appears in many
countries including Britain Canada and
Australia and we know there's a causal
connection between lead exposure and
antisocial or violent Behavior a study
of 340 teenagers found that those who
were arrested were four times as likely
to have elevated lead in their bones
than similar demographic controls who
didn't have run-ins with the laws now
this doesn't mean that lead is
responsible for all of the increase in
crime but it's very likely responsible
for some of it
now it's tough to estimate the precise
death toll of lead one of its lesser
known effects is a hardening of the
arteries leading to increased
cardiovascular disease a study from 2018
found lead was likely responsible for
250,000 heart disease deaths per year in
the US assuming a constant rate over the
past Century that amounts to 25 million
deaths in the us alone globally the
figure may approach 100 million
most of those deaths are due to mle's
decision to put lead in gasoline a
substance he knew firsthand was toxic
but he did it anyway to maximize profits
and the problem is not over current
estimates of deaths caused by lead range
from 500 to 900,000 per year a 2020
UNICEF report warns that one in three
children globally that's over 800
million children have blood lead levels
at or above 5 microG per deciliter a lot
of this lead now comes from batteries
and Industrial processes but some is
still due to mle's
invention now after mle's success with
Ethel he was put in charge of another
engineering project GM wasn't just
making cars but also household
appliances and fridges had a problem the
two most common gases used as
refrigerants were methyl formate and
sulfur dioxide one is highly toxic the
other is flammable Midgley was tasked
with creating a safer alternative and in
1928 he developed a non-toxic and
non-flammable refrigerant Doro Doro
methane GM called this new product Freon
and to demonstrate Freon safety during
the unveiling at the American Chemical
Society Midgley inhaled a lung full of
this gas and blew out a
candle in the following decades cfc's
like Freon became very popular and were
used as as solvents and aerosols the
problem is cfc's are light and stable
when released into the atmosphere they
climb up into the stratosphere where
they can remain for 50 to 100 years but
if a CFC molecule is hit by an
UltraViolet Photon of just the right
energy it breaks apart releasing a
chlorine atom and this chlorine atom can
then react with ozone breaking it apart
into chlorine monoxide and oxygen gas
the result was another environmental
disaster the hole in the ozone layer
with less ozone more UV light penetrates
the atmosphere increasing the rates of
skin cancer and cataracts plus cfc's are
potent greenhouse gases per kilogram
they produce 10,000 times more warming
than CO2 the historian John mcneel wrote
that mgle had more impact on the
atmosphere than any other single
organism in Earth's history an agreement
to phase out cfc's the Montreal protocol
went into effect in 1989 and the ozone
layer is now showing signs of recovery
although it'll take many more decades to
fully recover in 1940 at the age of 51
Midgley contracted polio and became
physically disabled so to help him get
up he devised a mechanical bed
controlled by a series of ropes and
pulleys on November 2nd 1944 while using
the contraption he became Tangled in the
ropes and died of strangulation
thanks to the work of CLA Patterson it
became clear that the lead in our
environment is not natural burning lead
and combustion engines spread the toxic
element across the planet into the air
oceans the snow at the South Pole and
even our bones Japan was the first to
ban Leed fuel in cars in 1986 but other
countries soon followed suit Algeria was
the last to do so in
2021 the UN calculates that the
elimination of lead from gas saves over
a million lives per year and $2.45
trillion but leted gas is still used by
the way in piston driven airplane
engines that's now the largest source of
lead emissions into the air in the
US you will observe with concern how
long a useful truth may be known and
exist before it is generally received
and practiced on
when I first learned about Thomas
Midgley and Clare Patterson I was amazed
by how much harm or how much good a
single person could do to the
environment which brings me to the
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