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Sadly, it’s no longer possible to purchase this lethally radioactive element for fifteen cents and a cereal boxtop.
Featured above: Two of the brightest minds in the history of science, even disregarding any radioluminescence.
Update 2021-07-20: Alas, for the same reason that I’m on a slower schedule, I’m afraid I have no show notes for this episode. Similarly, I can’t provide the nicely footnoted references that I usually do. However, I think it’s irresponsible to not provide them somehow, so if you’re interested, I invite you to visit the Sources at the bottom of this page (above the comments). They are messy, they are disorganized, but they are there and they are comprehensive. Thankfully, the URLs provide some hint about the information contained therein.
Group 16 elements have a reputation for causing unpleasant odors. Usually not oxygen, but the next three elements are sulfur, selenium, and tellurium. Those are responsible for some of the foulest molecules on the planet.
The next one down the line is polonium. And its odor… well, no one really knows what its odor is. It’s so incredibly radioactive that it would kill anyone who tried to find out, long before they could catch a good whiff.
Not every element from here on out is quite that bad, but they can get pretty nasty.
This might sound like a problem for a person who’s collecting samples of each element. Indeed, several of the elements in the table’s final period will remain out of reach — some of them only exist for a few seconds at a time.
But we’ll get creative where we can. So even though polonium is some of the most dangerous stuff on the planet, there are still safe ways to add it to our collections. And if nothing else, I can promise that it won’t stink up your home.
You’re listening to The Episodic Table Of Elements, and I’m T. R. Appleton. Each episode, we take a look at the fascinating true stories behind one element on the periodic table.
Today, we say “dzień dobry” to polonium.
It is my great pleasure to finally introduce Marie Salomea Skłodowska Curie and her husband Pierre. We’ve met husband-and-wife teams before, like the Galvanis and the Lavoisiers, but probably no scientific couple is more renowned than the Curies.
Such acclaim is well deserved. To say their list of accomplishments is “impressive” would be a massive understatement. In 1903, Marie became the first woman to win a Nobel Prize, sharing that year’s title in Physics with Pierre and their colleague Henri Becquerel. In 1911, she won the Prize in Chemistry, and she remains the only person to win Nobel Prizes in two different sciences.
Pierre, meanwhile, made important discoveries about heat, electricity, crystals, and the interplay among them. He later established the concept of symmetry, the same one that Chien-Shiung Wu would turn topsy-turvy in her experiments with cobalt.
As a duo, Marie and Pierre discovered today’s element, then followed it up by discovering radium a few months later. Marie did not discover radioactivity — that was her coworker, Becquerel — but she did coin the word, and the three of them wrote the book on this strange, powerful, invisible phenomenon. (Several books, actually.)
Pierre and Henri both came from privileged families, but Marie’s background couldn’t have been more different. The other two were born to well-off French families, while she was the youngest of five children in Warsaw. Today that’s the capital of Poland, but at the time, that area was jointly occupied by the Germans, the Russians, and the Austro-Hungarians. She had to go to Russian schools during the day, and at night she attended and taught at an illegal underground Polish school known as a “Flying University.” Every couple of nights, the school would switch locations to avoid the watchful eye of the Imperial Russian government.
Her father lost the family’s savings in a bad investment, and her mother died of tuberculosis when she was ten. She scraped together her meager earnings as a teacher and governess, and in 1891, she enrolled at the Sorbonne in Paris. She was quite poor, though, and what little money she had usually went toward her education rather than food. She developed a bit of a reputation for fainting due to a lack of sustenance.
That period of her life was over by 1893, thankfully. She earned her master’s degree in physics and married her lab director, Pierre. Let me dispel any notions that this was some marriage of convenience or borne out of a desire for a full belly: Marie certainly had experience with bad relationships from her time as a governess — it wasn’t quite The Sound Of Music, I’m afraid — and this was something quite different. By all accounts, their relationship was the very picture of true love.
She had always intended to return to Poland after completing her studies, but ultimately she found herself drawn more toward Pierre. “Our work drew us closer and closer,” she later wrote, “until we were both convinced that neither of us could find a better life companion.”
That work was just as essential to their relationship as their romance. For their wedding, Marie didn’t want a bridal gown. Instead, she wrote to Pierre, “If you are going to be kind enough to give me [a dress], please let it be practical and dark so that I can put it on afterwards to go to the laboratory.”
That is where they spent most of their time. In 1898, they were studying pitchblende, a radioactive compound that contains a lot of uranium. Strangely, though, even when they removed all the uranium, the material still emitted radiation — quite a lot of it, actually. Further investigation revealed the existence of an as-yet-unknown element.
They decided to name it polonium, for Marie Curie was still Polish at heart. This was a rather bold political act, because Poland kind of didn’t exist at the time. It was split up between Germany, Austria-Hungary, and Russia, if you’ll recall, and her homeland was officially known only as “Privislinski Krai.” It was a direct affront toward the empires, particularly Russia, who did not appreciate the gesture. Curie was hoping to draw attention to the oppressive situation in Poland, and you could say she was successful in that regard. Twenty years later, Poland would once again be an independent nation. That happened due to the efforts of thousands of Poles, of course, but the Curies certainly drew attention to the cause.
The most notable feature of element 84 is its extreme radioactivity, and the danger thereof. It didn’t take long to figure that out, because a technician in the Curie lab died after polonium was accidentally released from a distillation vessel.
We know a fair bit more about radioactivity then the people at the turn of the twentieth century, and it’ll probably do us some good to review some of that information before we go any further. After all, it will be relevant for every element we encounter from here on out.
“Radioactivity” is the energy that gets released when an atom decays. It’s often called “ionizing radiation” because that energy can strip the electrons clean away from atoms in their path, giving them an electrical charge and generally causing all sorts of havoc. There are many different kinds of ionizing radiation, but for now, let’s focus on three of the most common types: alpha, beta, and gamma radiation.
In the same way that light is carried by photons, the energy released by nuclear decay is carried by alpha particles, beta particles, or gamma rays, respectively.
An alpha particle consists of two protons and two neutrons. It’s pretty large — you might recognize that as the nucleus of a helium atom. It can carry a lot of energy, but being so big, it usually can’t penetrate biological tissue to cause damage. For instance, a piece of paper is enough to stop an alpha particle in its tracks.
Beta particles are simply electrons, or their antimatter equivalent, positrons. They carry a lot more energy, and they’re about 8,000 times smaller than an alpha particle. Being smaller and more energetic, they can pass through more materials before they’re stopped. You’d need a sheet of aluminum foil to block beta radiation.
Gamma rays are an extremely high-energy form of electromagnetic energy that don’t have any mass at all. This allows them to penetrate deeply into materials, especially causing damage to biological tissue. A thick wall of lead will absorb a lot of gamma radiation, but even then, a little bit will still pass through.
The kind of radiation that polonium emits is alpha radiation, and that’s what makes it so deadly. Wait, what? Wasn’t alpha radiation the kind that harmlessly bounces off a sheet of paper?
That’s right. Your skin is highly effective at blocking alpha radiation. The danger isn’t posed by polonium outside your body, then, but by any that happens to get inside of your body — eaten, inhaled, or injected. It gets swiftly carried to the kidneys, liver, spleen, and bone marrow, where those big, highly charged alpha particles can bombard some of the body’s most sensitive tissues at point-blank range.
It doesn’t take a lot of polonium to kill a person. Less than a single microgram will do the trick, making it second only to botulinum in terms of pure, concentrated toxicity.
As you might imagine, this presented something of an occupational hazard for the Curies. Indeed, she died in in 1934 from leukemia, probably as a result of all the work she did with polonium, radium, and x-rays over the previous decades. Actually, the Curies had a daughter, Irene, who also won the Nobel Prize in Chemistry with her husband, and she also died from complications of leukemia as a result of her work. Like mother, like daughter.
When Marie died, she was buried in a wooden coffin inside a lead coffin inside another wooden coffin, due to fears about her radioactive remains. Even today, anyone wishing to study the Curies’ personal papers must wear special protective gear to minimize the risk of radiation poisoning.
Eventually, scientists learned how to deal with polonium in a relatively safe way — and the element gained notoriety as a more deliberate way to usher souls from this world to the next.
This became apparent to the world in late 2006 following the death of Alexander Litvinenko.
Litvinenko was an officer in the KGB, then the FSB after the fall of the Soviet Union. He specialized in operations against organized crime, which became a bit awkward when he discovered that the organized criminals in a given area often were the police officers and FSB agents. His exposure of widespread corruption within government agencies was not appreciated by the newly appointed president and prime minister of Russia, Vladimir Putin. Putin personally ordered Litvinenko’s dismissal from the FSB, and following a rash of suspicious deaths, Litvinenko fled to London. He was granted political asylum, and he continued to combat organized crime and bring attention to Putin’s abuses of power.
Then on November 1, 2006, Litvinenko fell suddenly ill. Intense nausea, gastric pain, and difficulty walking led to his admission to Barnet Hospital. Doctors suspected he might have been poisoned with thallium, but a passing scientist happened to overhear details of the case and recognize the signs of polonium decay.
There wasn’t much anyone could do, unfortunately. There is no remedy for polonium poisoning. Over the course of the next month, Litvinenko’s skin yellowed, his hair fell out, his bone marrow was destroyed, and he eventually died of a heart attack on November 26 — three and a half weeks after he was poisoned.
Polonium is a highly effective poison, but it has some drawbacks. For one, it tends to leave a tell-tale trail of radiation everywhere the assassin goes, which made it simple for investigators to trace a path back to former KGB agent Dmitry Kovtun. Litvinenko believed that his assassination was personally ordered by Putin himself. In his last public statement, he said, “You may succeed in silencing one man, but the howl of protest around the world, Mr. Putin, will reverberate in your ears for the rest of his life.” On November 27, Putin responded: “Mr. Litvinenko is, unfortunately, not Lazarus.”
However offended the Russian government might have been by the naming of polonium, that didn’t seem to stop them from adding the element to their arsenal of secret weapons. Supposedly. Allegedly.
After hearing all that, it might surprise you to learn that it’s really not difficult to get your hands on element 84.
It’s used as an essential component of anti-static brushes, which are mainly used to clean vinyl records, microscope slides, and other surfaces that build up a static charge over time. Dust is attracted and sticks quite stubbornly to surfaces that carry a static charge. The polonium ionizes the air within a few centimeters, which allows the brush to easily knock that dust loose.
Great care needs to be taken in the manufacture of these brushes, due to… everything we’ve covered in this episode. The polonium is securely encased within foils of silver, gold, and nickel, and for safety’s sake, the polonium isn’t actually created until it’s already sealed up. It’s pretty clever: A thin foil of bismuth is sandwiched between the other metals, then blasted with a beam of neutrons that transmutes some of the bismuth into polonium. The surrounding environment is never exposed to the material. Nothing like a little light alchemy to meet OSHA regulations.
A spinthariscope is a scientific curiosity invented by William Crookes in 1903. It’s kind of like a kaleidoscope, except instead of colored glass or plastic at the far end, it holds radioactive material behind a special screen that lights up every time it’s struck by an alpha particle. It’s pretty neat, and in 1947, you could get your own polonium-fueled Lone Ranger-brand spinthariscope in exchange for a boxtop from KIX cereal and fifteen cents.
Attitudes have changed a bit in the 74 years since.
If you stumble upon one of those toys, you might want to snatch it up. It won’t have any polonium in it anymore — its half-life is around 138 days, so it all transformed into lead a long time ago. The same thing will happen to an anti-static brush, or indeed, to any sample that contains a little polonium. That’s another problem we’ll have in collecting element samples going forward: Whether quickly or slowly, the radioactive element will eventually decay into something else.
You could purchase a new spinthariscope or anti-static brush every couple of years — that’s what Theodore Gray, the Ur-Element Collector, does. But in my humble opinion, it’s perfectly acceptable to find yourself a sample of something that used to contain whatever element you’re looking for. Don’t worry — even the more stable samples of remaining elements will be more than sufficient to light up a Geiger counter like the Fourth of July.
Thanks for listening to The Episodic Table of Elements. Music is by Kai Engel. To learn who else the Russians may have possibly allegedly assassinated with polonium, visit episodic table dot com slash P o.
Next time, we’ll meet an element with self-destructive habits: astatine.
Until then, this is T. R. Appleton, reminding you that although radioactivity can be very spooky, there is absolutely no empirical proof that a stream of protons can harness “ghost energy,” as proposed by Drs. Egon Spengler and Ray Stantz.
5 Replies to “84. Polonium: The Distinguished Alumna Of Warsaw’s Flying University”
Next chalcogen element?
Is polonium is a metal? There are some sources that it’s a metal and other sources a metalloid. If so then is the only metallic chalcogen?