Strange Glow: The Story of Radiation, written by Georgetown professor of radiation medicine Timothy Jorgensen and released this month, is a fascinating account of how radiation has both helped and harmed our health. While much of the book is concerned with explaining radiation risks so that consumers can better understand them (one takeaway fact: airport scanners expose you to less radiation than waiting in line for them does), it’s also full of intriguing, if occasionally horrifying, facts and anecdotes about the history of the "strange glow" that has transformed our lives.

1. X-RAYS MOVED FROM THE LAB TO THE HOSPITAL IN RECORD TIME.

Montreal resident Toulson Cunning had an unfortunate Christmas Day in 1895: For reasons Jorgensen does not relate, Cunning was shot in the leg. The injury occurred just a few weeks after German professor Wilhelm Conrad Roentgen noticed a faint glow on a fluorescent screen in his lab while experimenting with cathode rays and a glass vacuum tube. Roentgen’s first paper on the subject, “On a New Kind of Rays,” was published in a local journal on December 28, 1895, and was rapidly picked up in the both the scientific and popular press. A professor at McGill University in Montreal soon replicated the experiment, and after hearing about it, Cunning’s doctor asked for an x-ray of his patient's leg. After a 45-minute exposure, the image was still somewhat faint, yet clear enough for surgeons to see the bullet and remove it—thus saving Cunning’s leg from amputation barely six weeks after Roentgen’s discovery. As Jorgensen tells it, “Never before or since has any scientific discovery moved from bench to patient bedside so quickly.”

2. THE STANDARD UNIT OF RADIOACTIVITY IS NAMED FOR ITS ACCIDENTAL DISCOVERER.

Henri Becquerel. Paul Nadar via Wikimedia Commons // Public Domain

Henri Becquerel, his father, and his grandfather were all chairs of the Department of Physics at the Musee d’Histoire Naturelle in Paris, and all conducted experiments on fluorescence and phosphorescence—you might call it their family obsession. The men had even amassed a vast collection of fluorescent minerals to use in their studies.

Becquerel was intrigued Roentgen’s discovery of x-rays, and wondered if any of the minerals in his collection might emit them. He tried a series of experiments in which he sprinkled flakes of various fluorescent materials onto photographic film wrapped in black paper, leaving them outside in the sun to stimulate the fluorescence. To his surprise, the only one that seemed to expose the film at all—whether there was any sunlight or not—was uranium sulfate, which left a faint impression of its granules. Becquerel soon discovered that this property of uranium didn’t have anything to do with x-rays or even fluorescence: It was uranium’s own special type of radiation. By trying to understand fluorescence, Becquerel had discovered radioactivity. He was awarded the Nobel Prize in Physics in 1903, alongside Marie and Pierre Curie, for his discovery, and the standard international unit for measuring radioactivity is today named the becquerel in his honor.

3. POLONIUM IS NAMED FOR MARIE CURIE’S HOMELAND, POLAND.

Marie Curie's notebook containing notes of experiments, etc. on radioactive substances. Image: Wellcome Images // CC BY 4.0

The Curies eventually outstripped Henri Becquerel when it came to radioactivity research—to start, they were the ones who introduced the term “radioactive." The pair showed that uranium ore contained at least two substances more radioactive than uranium itself, both previously unknown to science—radium, derived from the Latin for ray, and polonium, named for Marie’s native Poland, then under Russian control.

The Curies would go on to work with so much radiation (and make so many key discoveries) that there was a concern after Marie's death from aplastic anemia in 1934 that her skeleton might be radioactive. When tested during a reinterment in 1995, it wasn't, although her papers still are. (Pierre had died much earlier, in 1906, after an accident with a very non-radioactive horse cart.)

4. MANY OF THE PIONEERS OF RADIATION RESEARCH WERE PRETTY CONFUSED.

Many of the earliest discoverers of radiation and radioactivity didn’t have a great understanding of how their discoveries worked. For example, Becquerel believed for a while that radioactivity was a type of fluorescence, while Marie Curie proposed that uranium and similar elements could absorb x-rays and release them later as radioactivity. Even Guglielmo Marconi, awarded the 1909 Nobel Prize for his work on radio waves, “freely admitted, with some embarrassment, that he had no idea how he was able to transmit radio waves across the entire Atlantic Ocean,” according to Jorgensen. Classical physics said that radio waves shouldn’t have been able to go nearly that far; it was only later that scientists understood that radio waves can cross the globe because they bounce off a reflective layer in the upper atmosphere.

5. RADON WAS THE FIRST RADIOACTIVE ISOTOPE LINKED TO CANCER IN HUMANS.

Radon, produced when radium decays, was first proposed as the cause of lung cancer among German miners in 1913. World War I interrupted further study of the subject, however, and the link between radon and cancer was only accepted after a thorough review of 57 studies published up until 1944.

6. THE PUBLIC LEARNED ABOUT THE DANGERS OF RADIOACTIVE SUBSTANCES THANKS TO THE “RADIUM GIRLS.”

"Radium Girls" at work. Wikimedia // Public Domain

In the 1910s, young women in Connecticut, New Jersey, and Illinois who painted glow-in-the-dark watch dials with radium-laced paint became known as the “Radium Girls.” Perhaps ironically, the wristwatches were specifically marketed to men, who until then had been more likely to wear pocket watches. The glow-in-the-dark dial was popular among soldiers, and thus seen as adding a touch of manliness.

Unfortunately, the women who painted the dials frequently sharpened their paintbrushes by twisting the fibers in their mouths, ingesting small bits of radium as they worked. According to Jorgensen, over the course of a year workers would have consumed about 300 grams of paint. Not surprisingly, the workers began dying of cancer and bone disease, and “radium jaw” became a new type of occupational disease. The watch companies were forced to pay out thousands of dollars in settlements, and the girls began wearing protective gear, including fume hoods and rubber gloves. Sharpening their brushes in their mouths was also banned. But it was too late for some: “By 1927, more than 50 women had died as a direct result of radium paint poisoning," according to NPR.

7. BUT RADIUM WAS STILL SOLD AS A HEALTH TONIC.

Radium ad from 1916. Wellcome Images // CC BY 4.0

Despite the press the Radium Girls received, radium remained on the market as a health-giving tonic. One noted victim was industrialist and amateur golf champion Eben McBurney Byers, who was prescribed Radithor (radium dissolved in water) by his doctor. He proceeded to drink about 1400 bottles of it over the next several years, losing much of his jaw and developing holes in his skull as a result. He died in 1932, about five years after starting his Radithor habit, and now rests at a Pittsburgh cemetery in a lead-lined coffin—reportedly to protect visitors from radiation exposure.

8. THE MANHATTAN PROJECT RAN A SECRET RADIATION BIOLOGY PROGRAM CALLED THE "CHICAGO HEALTH DIVISION."

When the Manhattan Project began in 1939, the effects of radiation on human health still weren't well understood. Staff modeled their protective fume hoods and ventilation systems on the ones used to protect the Radium Girls, but to bolster their knowledge, they also started a new radiation biology research program, code-named the Chicago Health Division. The impetus for the project came from its own physicists, who were concerned about their life expectancy.

9. YOU CAN THANK A RADAR ENGINEER FOR YOUR MICROWAVE.

Raytheon Radarange aboard the NS Savannah nuclear-powered cargo ship, installed circa 1961. Image by Acroterion via Acroterion via Wikimedia // CC BY-SA 3.0

Radar, which often uses microwave signals, was developed in secrecy by several nations in the years before WWII. In the U.S., a secret lab at MIT worked on improving radar deployment, and contracted with a company called Raytheon to produce magnetrons (microwave signal generators) for their labs.

One day, a Raytheon engineer working on the project, Percy Spencer, noticed that a candy bar in his pocket had completely melted while he was working with a radar apparatus. Intrigued, he focused a microwave beam on a raw egg, which exploded. He later realized he could also use the microwaves to make popcorn. It wasn’t long before Raytheon lawyers filed the patent for the first microwave oven, which they called the Radarange.

10. EXPOSED X-RAY FILM HELPED HIROSHIMA SURVIVORS FIGURE OUT THEY'D BEEN HIT WITH AN ATOMIC BOMB.

When the atomic bomb was dropped on Hiroshima on August 6, 1945, the populace had no idea what kind of bomb had hit them. Doctors at the Red Cross hospital got their first clue when they realized that all the x-ray film in the facility had been exposed by the radiation. (It would be a week before the public learned the true nature of the weapon that had devastated their city.) With no need for the exposed film, hospital staff used the x-ray envelopes to hold the ashes of cremated victims.

11. HIROSHIMA AND NAGASAKI SURVIVORS HAVE BEEN KEY TO UNDERSTANDING RADIATION’S EFFECT ON HEALTH.

In the months after the Hiroshima and Nagasaki bombings in 1945, scientists realized the events provided an important opportunity to study the effects of radiation on human health. President Harry Truman directed the National Academy of Sciences to begin a long-term study of the bomb’s survivors, which became the Life Span Study (LSS). The LSS has been tracking the medical history of 120,000 atomic bomb survivors and control subjects from 1946 up until the present. Jorgensen calls the LSS “the definitive epidemiological study on the effects of radiation on human health.”

Among other results, the LSS has provided an important metric—the lifetime cancer risk per unit dose of ionizing radiation: 0.005% per millisievert. In other words, a person exposed to 20 millisieverts of radiation—the amount in a whole body spiral CT scan, according to Jorgensen—has a 0.1% increased lifetime risk of contracting cancer (20 millisieverts X 0.005% = 0.1%).

12. THE U.S.’S LARGEST NUCLEAR WEAPONS TEST INCLUDED A MAJOR MISTAKE.

The Castle Bravo blast. US Department of Energy via Wikimedia // Public domain

On March 1, 1954, the U.S. conducted its largest-ever nuclear weapons test, code-named Castle Bravo, at the Bikini Atoll in the Marshall Islands. The hydrogen bomb that exploded—nicknamed “Shrimp”—released more than twice the energy scientists had predicted: 15,000 KT of TNT instead of the anticipated 6000 KT. According to Jorgensen, the extra punch was thanks to an error in the calculations of physicists at Los Alamos National Laboratory, who failed to understand that two, not one, of the lithium deuteride isotopes would contribute to the fusion reaction. The mistake, combined with some unreliable winds, produced fallout in a much larger zone than expected. Among other effects, it contaminated a Japanese fishing boat, Lucky Dragon #5, which led to a diplomatic crisis between Japan and the U.S.

13. THE BIKINI ATOLL WAS RESETTLED—TO DISASTROUS EFFECT—THANKS TO A VERY BAD TYPO.

Before the Castle Bravo tests, the inhabitants of the Bikini Atoll were asked to relocate to another nearby atoll for a project that would benefit all of humankind (according to archaeologists, this ended close to 4000 years of habitation on the atoll). The island of Bikini wasn’t resettled until 1969, until what Jorgensen calls a “blue-ribbon panel” estimated that their risk of radioactivity exposure would be low enough to be safe. Sadly, the panel based its advice on a report with a misplaced decimal point, which underestimated the islanders’ coconut consumption a hundredfold.

The problem wasn’t discovered until 1978, when the islanders were evacuated again. Many have suffered from thyroid and other cancers, and the U.S. has paid more than $83 million in personal injury awards to the Marshall Islanders since then; according to Jorgensen, however, millions remain unpaid, and many of the claimants died while waiting for their settlements.

14. A PENNSYLVANIA HOME HAD ONE OF THE HIGHEST RADON CONCENTRATION LEVELS EVER RECORDED.

In 1984, Stanley Watras repeatedly set off the radiation detector alarms at the nuclear power plant where he worked. Investigators eventually realized his work wasn’t the problem, and traced the contamination via his clothes to his home, which was discovered to be sitting on a massive uranium deposit (radon is produced as part of the uranium decay chain). The Watras family house was found to contain about 20 times as much radon gas as a typical uranium mine. The discovery led the U.S Environmental Protection Agency to survey other homes, and to discover that many in America had hazardous levels of radioactive gas.

The Watras family was told they were seven times more likely to die of lung cancer in the next 10 years than the average person, and that their young children might not live until adulthood. The risk proved to be overestimated: 30 years later, none of them have died of lung cancer. The house was later used as an EPA laboratory for radon remediation technologies, and the family was able to move back in. Stanley and his wife still live there, according to Jorgensen.

15. THE RISK OF NUCLEAR POWER PLANTS HAS BEEN DIFFICULT TO ESTIMATE.

In the early 1970s, an MIT professor of nuclear engineering named Norman Rasmussen headed a federal committee charged with determining the risk of a nuclear reactor core accident. The report concluded that the odds of such an accident at a commercial nuclear power plant were 1 in 20,000 per reactor per year.

The Rasmussen report, as it came to be known, is now seen to have severely underestimated the odds. Just four years later, in 1979, the Three Mile Island accident occurred, in which a nuclear reactor partially melted down. Later studies have estimated other odds, but based on data from the International Atomic Energy Agency, Jorgensen estimates that the accident rate is closer to 1 in 1550 operational years. With 430 operational nuclear reactors in the world, Jorgensen writes, we could reasonably expect a significant reactor core accident once every 3 to 4 years—at least based on accident rates in the past.