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 fissile fuel for bombs from the much more common uranium-238 and this required huge machines, mass spectrometers, separated 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, wait which uh it takes the mass of one and one that is really closer and it boom or 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 four and a half billion years for half of a sample of u-238 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 that's but he's his instrument.

First, he used zircon crystals, whose ages were known. Zircon 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 zircon, you know, must be the product of a uranium. Oh and they apply, the ratio. Patterson was tasked with measuring the lead content and another student.

George tilton, measured uranium tilton's uranium measurements were fun. Sadly, but patterson's lead measurements were all over the place and they were many many times higher than they expected. We take georgia'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 claire patterson's life and bring him to the literal ends of the earth soil. So soil and has led to no weight vitamin driving across the belle isle bridge. In detroit, when her 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 auto 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. Jesus dude, cleveland, hired charles kettering, 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 crankless car was the cadillac model 30.. It was much more powerful than cars before it.

It had a top speed of 45 miles per hour. 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 definitely loud.

Oh 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, pushed the piston back down the problem. With the model 30 engine was it compressed the fuel air mixture? Oh wow, i get it in 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, haphazard, combustions, leading to turbulent pressure waves inside the cylinder, the resulting sound Led the problem to become known as engine 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 heptane, for example, will spontaneously combust under only a little compression iso octane, on the other hand, can withstand. I know that it is a very simple ratio before it auto ignites, so it's much less likely to cause knocking to quantify how much compression a fuel came up with the octane rating system. They arbitrarily set iso-octane to have a rating of 100 and n-heptane 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 octane rating tells you what mixture of octane and heptane gives equivalent performance.

For example, 98 octane fuel can withstand the same compression as a mixture of 98 octane and 2 percent 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 oh jesus christ, nothing happens which is exactly what you'd expect this fuel can withstand. A lot of compression diesel has an octane rating of 20.. So it acts like a mixture of 20 percent iso.

I was going to block 50 and heptane. If i put a little bit of diesel in there, let's see what happens with the same compression ratio. Wait just with compression 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. Yeah you got ta keep track, which would increase the octane rating of ordinary fuel and eliminate knocking in high capacity, because how much dollar is it to fuel your car to full, when it's like almost out entirely how much dollar i'm just wondering? 70 bucks. 80 bucks. 60.

40.. Damn that varies a lot: 175 dollar eddie, interesting, 110 euros yeah, but you're also like. Why not believe money dude euros they're everywhere your heroes are pretty much free, so he hired 27 year old engineer, thomas midgley jr midgley experimented with all sorts of compounds from melted butter and camphor to ethyl acetate and aluminum chloride. He later wrote down no more effect than spitting in the great lakes.

Ethanol was an interesting usd euro, oh exception. It did stop the knocking, but you needed a lot of it about 10 percent of the fuel mixture for it to be effective. That much ethanol would be expensive and hard to turn a profit on and midge. Trustley 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 tellurium. It worked wonderfully as an anti-knock agent. Oh, no, it had a terrible, i missed it, it was gbp sorry. Yes, i missed it, you guys usd gbp sorry.

I forgot my number ah see wait a minute, we'll 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 why he said what now then he hit on tellurium. It worked wonderfully as an anti-knock 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 seven months. Midgley wrote. I don't think that, although this doubled the fuel economy, humanity would suffer this smell on december 3rd 1921, after five 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 affected and the rest binds to it in a call to kettering midgley said: can you imagine how much Money we're gon na make with this we're gon na make 200 million dollars, maybe even more, that is over three billion in today's dollars. 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 midgley declined. He and kettering patented the process for making tetraethyl lead and they called their new additive ethyl.

Perhaps so it might be confused with another additive ethanol, alcohol. They made no mention of lead. Then they teamed up with three of america's largest corporations: general motors dupont and standard oil, new jersey dupont 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, the top three finishers all used ethel and the demand for leaded gasoline took off to keep up. Ethel corporation had to build a new chemical plant in new jersey. But the project began terribly within two months of operating, dozens of workers fell ill with lead poisoning.

Five of them died. That's not a joke, led poisoning, a public outcry, midgley 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 midgley 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, no yeah, whatever island 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 have been known for health. Is that alzheimer's or um, because there's uh failed signals or whatever the signal doesn't get there properly, because uh you need the sheet to protect it or whatever. The right 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 aghast to learn that nearly 150 years later, scientists planned to add lead to fuel doctors and public health officials from mit harvard yale and the u.s health service wrote to midgley and warned them against producing tetraethylene. They called lead a creeping and malicious poison and a serious menace to public health. Their concerns were dismissed. Huh.

This model shows how just the right amount of fluid containing tetraethyl, lead and dye is. Are you playing video game today? We're just studying content today, i'm um. So i ordered some some ski masks, i'm about to put that on and i'm about to go robbed in it of all its riches and that's all it's videos, dude i got gloves. I got the whole thing i might encrypt the broadcast, so don't get caught with all this robbery.

You shut the up to the gasoline. No one doubted that a lot of lead was bad for you, but how much harm could a little lead? Do millions of motorists globally were burning, lead in their cars and releasing it into the air? Some of that lead ended up on claire patterson's zircon samples preventing him from determining their age. In 1952, he moved to caltech where he built a new lab from scratch. Suspicious 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 well, i mean - were there at the very very beginning of everything.

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. They could be. 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. What scientists, okay, that makes literally no sense, you guys don't normally work backwards.

Chin claimed that lead was a natural part of our environment. We can do this if it's safe, not we're rolling it. We're rolling really hard we'll continue uh, but maybe it's unsafe, but whatever we'll stick it out for 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 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, i'm confused about some of this guys is it. I won't make this a weird discussion, but isn't it most like the drugs and like? Oh, don't do this health concern blah blah blah, but right right right, but isn't this kind of like the same, doesn't like the if they has to approve this or something like that? Like hey man, this is poisonous this just like any any drug or other compounds are right. Nope.

He expected the concept. This technically is it's just worse. Creation of lead to be the same regardless of depth, but if lead pollution had increased recently, it would be more concentrated near the surface. It was the 70s samples in the pacific and atlantic oceans down to a depth of four kilometers 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, 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 oars, 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 industrialization and wait, that's insane, that's so cool! They could see a history in in a graph 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 guys it's almost like some, some completely unrelated topic. Whatever will tell you literally world history, no, i think it's cool 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 all made up in their lifetime.

Dude go outside, i'm gon na get my little. If you go him up, he expected to find modern americans having 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 is a broad consensus on the part of everybody, except the lead industry and its spokesman. That led is extremely toxic in 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 guys guys still down Sit down: okay, i'm gon na i'm gon na go get a test or some i'm gon na go. I'm gon na go check the lead in my teeth and you know what they're gon na say: it's a gift from heaven, so we don't know what's gon na happen, there's none zero.

How did it happen? Grams per deciliter, down to 3.5 non-zero, and as far as we know today, there is no safe level of lead globally led is believed to be responsible for nearly two-thirds of all unexplained intellectual disability. According to a study published in 2022, more than half of the current u.s population - that's 170 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 let it go yeah guys. Do you think if you think that my stream does more than that, if you were to check it iq points, the world is less intelligent today because of leaded gasoline, but there are even more troubling correlations. The u.s saw a steady rise in crime from the 1970s to the 1990s. Then it abruptly declined.

This graph looks eerily similar to a plot of preschool blood. Lead levels just offset by 20 years. Wait a minute. The obvious question is: did kids, who were exposed to higher levels of lead grow up to commit more crimes than they otherwise would have? You might think this is just a spurious 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 anti-social 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 law. 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 u.s, assuming a constant rate over the past century. That amounts to 25 million deaths in the u.s alone. Globally, the figure may approach a hundred million. Does that most of you guys guys i mean if you have a a mother and she's pregnant or whatever anything that is lead related is like super bad because it it it affects the baby by a long shot or is it more like as a kid or Whatever are due to midgley's decision to put lead in gasoline a substance, he knew was toxic, but he did it anyway.

That's really bad then, and the problem is not over. Current estimates of deaths caused by lead range from 500 to 900 000 per year. The 2020 unicef report warns that one in three children globally - that's over 800 million children, have blood lead levels at or above 5 micrograms per deciliter. A lot of this lead now comes from batteries and industrial processes, but some is still due to midgley's invention after midgley's success with ethel, he was put in charge of another engineering project.

Gm wasn't just making cars. Oh, no, please hold appliances, the pens, the two most common gases used as refrigerants were methyl formate and sulfur dioxide. One is highly toxic. The other is qcc because of your recent tests.

Your lead levels are way above what should be level? How the are you still alive, executing a safer alternative and in 1928 he developed a non-toxic and non-flammable refrigerant dichlorodifluoromethane 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 oh, my god, this guy popular and we're used as solvents and aerosols. The problem is, cfcs, 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 cfcs are potent greenhouse gases per kilogram. They produce 10 000 times more warming than co2. The historian john mcneil, wrote that midgley had more impact on the atmosphere than any other single organism in earth's history.

An agreement to phase out cfcs, the montreal protocol went into effect in 1989 and the ozone layer is not any 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 claire 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 with the south pole and even guys our bone guys. At the time you guys didn't, i don't think they had the the stuff um to fully test everything.

I think the guy was trying to make products that worked that were needed. I don't think he tried to purposely hide stuff. Did he? Japan was the first to ban leaded 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 dollars, but leaded 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 claire 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 sponsor of this video ren, an organization, that's taking action on climate change. I think it's important that we tackle the climate crisis both by lobbying for systemic change and by making more environmentally friendly choices. I think we could truly appreciate these ads. Okay um.

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I feel bad watching this video better. You guys, i didn't mean pay attention um. Oh my god. I banned some guy eight times there you go.

Give me a like and boom apparent with photos and details of every tree planted every acre reforested. Every ton i don't have an it just it just is a bad newser and i just kept spending it in the description. I will personally pay for the first month of your subscription, so i want to thank ren for supporting veritasium, and i want to thank you for watching. I enjoyed it.

That was a good video yeah. I watched a little bit of the of the dupont evil, where they're like, like completely covering it up and being really um crazy and dumb. So i knew like lead was really bad. I didn't know it was that bad though give me tonight,.