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The fascinating history of radon and why you should care

Updated: Feb 8, 2023

A closer look at the element that was once in high demand to treat cancer and is now known as the leading cause of lung cancer in non-smokers.

Atomic Structure of Radon Source: Wikipedia

Radon is a naturally occurring gas released by uranium, radium, and other radioactive elements decaying in the soil and rocks beneath us. It was initially discovered as an ‘emanation’ of radium, and eventually given the name radon. Radon was discovered in 1900 by Friedrich Ernst Dorn, a German chemist studying the properties of radium.

Before the Discovery

Radioactivity was still very new in the late 1800s. In fact, Marie Curie hadn’t even coined the term yet. X-rays had only been discovered five years before, in 1895, and weren’t fully understood either. In 1896 Chicago physician Emile Grubbe attempted the first use of radiation to cure cancer. He tried applying the newly discovered x-rays to a patient with breast cancer, according to the Royal Society of Chemistry (RSC). He was not successful, but radiation remained the hot new thing.

Around the same time, Henri Becquerel discovered that uranium would fog film and believed uranium had something phosphorescent, or glowing, about it. The ‘activity’ of these rays and uranium inspired Marie Curie, who was working at the Sorbonne in Paris, to investigate these invisible rays, and she referred to their effects as radioactivity. In 1898 she found that pitchblende, an ore mostly composed of uranium and oxygen, was three times more active than other ores containing uranium.

She believed, correctly, that there was something else going on, some other element present. She named it radium in 1898 and she and her husband spent the next four years isolating .1g of radium chloride, or radium salt, from 3 whole tons of pitchblende.

Caption: Pitchblende, pictured above, got its name from silver miners at Joachimsthal, a small town in the modern-day Czech Republic near the German border. When the miners would encounter the blackish ore it would usually mean the end of the silver vein. They named it pitchblende, or “bad luck rock”. (5)

Pierre Curie estimated that their new element, radium, was a million times more radioactive than uranium. At first, people tried using radium to produce an x-ray effect but found that it penetrated bone too easily (Yikes!), making it hard to see anything clearly inside the body (2). Still, doctors found that skin lesions and cancers reacted to exposure from radium and radium salts.

In 1901 Pierre loaned a small sample to doctors in Paris, where it was successfully used to treat painful facial skin lesions from a type of tuberculosis called lupus vulgaris. Pretty soon after that, radium was used to treat a variety of skin cancers. As early as 1904, doctors were using radioactivity inside the human body as well. Some physicians would use a specially prepared ‘bobbin’ that patients would hold inside their mouths and throats to treat tumors in the same areas. Others used hollow needles filled with radium to access harder to reach tumors or to access all parts of a tumor.

Caption: From RSC. I couldn’t find a picture of the ‘bobbin’, but the dark lines in the picture above are the hollow needles used to treat this patient. Patients would have to lie completely still while the treatment was happening, ow!

The Discovery

While Friedrich Ernst Dorn is given credit most often, there is some academic debate over who most deserves that credit. In the interest of fairness, this is a list of the possible candidates:

  • Ernest Rutherford, 1st Baron Rutherford of Nelson, New Zealand and often called the father of nuclear physics

  • Robert B Owens, an American electrical engineer

  • Harriet Brooks, Canada’s first female nuclear physicist

  • The Curies, French physicists extraordinaire

  • Friedrich Dorn, German chemist, and physicist

The new phenomenon of radioactivity fascinated scientists everywhere!

After the Discovery

Radium treatments, while offering a long-awaited alternative to surgery, were not available to everyone and couldn’t be used to treat most internal tumors. Considering it took three tons of pitchblende, or 3,000 kilograms, to get .1g of radium salts, that made radium very expensive. You also couldn’t leave any of it in the human body for very long because of the burns. While the long-term effects of radiation hadn’t been discovered yet, medical staff and patients were aware that a longer session of radium treatment could cause intense burns.

That’s where radon comes in! Radon has a 3.8 day half-life before it settles down and becomes harmless so it was safer to insert in the body. Marie Curie developed the radon cow, a device that could be ‘milked’ for radon once every 20 days or so (4). The ‘cow’ was really a chunk of radium that gave off- or emanated- radon gas.

In 1920 doctors started using radon ‘seeds’, crimped pieces of gold foil holding small amounts of radon gas. These could be inserted and left in the body, even permanently, without causing any harm (3).

Caption: From the Oak Ridge Associated Universities (ORAU) Museum of Radiation and Radioactivity

Radiation is the Sensation Sweeping the Nation(s)!

Once these materials were more readily available and the public understood their benefits, the market was flooded with radon and radium related products(2). Fortunately, most of these products were full of false advertising rather than radiation. For example, the following German toothpaste ad, telling customers that the radon in the toothpaste would protect their gums, did not actually contain anything of the sort.

Radium salts, radon, and radiated water were touted to treat a wide variety of concerns, from hypertension to arthritis and a large variety of chronic pain conditions. Much like the supplementary market today, advice from the medical community was ignored. Other products included Vita Radium Suppositories, a product for men that was supposed to make “weak and discouraged men…bubble over with joyous vitality,” according to the RSC.

At least one product, however, was actually radioactive, much to the detriment of its users. Radithor, Certified Radioactive Water, was a patented medicine guaranteed to have two microcuries of radium per bottle. It was advertised as a ‘cure for the living dead’ and had at least one fan. American industrialist Eben Byers drank three bottles a day after he fell out of bed and injured his arm. From a 1932 Times Magazine article,

The dope eased the arm pain, braced Byers up. He enthusiastically recommended it to friends, sent them cases of it, even gave some to one of his horses. Last week Eben Byers died in Manhattan of radium poisoning. Eighteen months ago, after hundreds of drinks of the radium tonic, he began having pains in his jaw, severe headaches. Dr. Joseph Manning Steiner, Manhattan x-ray specialist, recognized in Byers’ condition symptoms of radium poisoning. Young in years and mentally alert, he could hardly speak. His head was swathed in bandages. He had undergone two successive operations in which his whole upper jaw, excepting two front teeth, and most of his lower jaw had been removed. All the remaining bone tissue of his body was slowly disintegrating, and holes were actually forming in his skull.”

The Watras Incident and Radon as a Public Health Hazard

It wasn’t until the 1980s that people had any idea that radon is a public health hazard.

In 1984 Stanley Watras was a construction engineer working on the Limerick nuclear power plant in Pottstown, PA. When he was leaving the work site he set off the radiation detector. The strange thing was nuclear fuel hadn’t been introduced to the plant. There shouldn’t have been anything to set off the detector!

According to Environmental Radon: Occurrence, Control, and Health Hazards, every time he left the site, he set off the detector. After days of this and the resulting safety concern for himself and others, he tried entering the site through the detector. Alarms rang out again!

From that he concluded, and others agreed, that the radiation must somehow be following him from his home. At around noon on December 19th, 1984 the Senior Health Physicist at the power plant called the Pennsylvania Department of Environmental Resources. That same day the department rushed to check out the home and found extremely elevated radiation. In some places of the home, there were more than 10 Working Levels (1 Working Level is considered the safe limit for uranium mines).

The measurement was put together quickly and not necessarily designed for being conducted in a house, but it was still immediately clear that Stanley, his wife Diane, and their two children, aged 2 and 4 were at serious risk. They were encouraged to leave the home and arranged to stay with out-of-state relatives over the holidays.

Another visit was needed, this time from the Bureau of Radiation Protection, after taking a day to familiarize themselves with the ‘language of radon’ and the risks involved.

With remarkably quick government turnaround time, the Bureau got together a variety of equipment to test the house for radiation. Unsure of what they were facing, the team measured the radiation levels in multiple ways:

- Film detectors that required several days of exposure. When the film was developed it would show damage from the particles passing through it.

- Air samples with activated charcoal. The charcoal absorbs the gas and then areas of decay, or decay products form, and measuring those will say how radioactive the area is. We still use this method in large commercial radon tests!

- MicroR meters, which are used to detect low levels of gamma radiation. Gamma radiation is extra dangerous!

- And more!

The table below shows the results they found:

The EPA today recommends “That Americans consider fixing their home for radon levels between 2pCi/L and 4pCi/L.” 4pCi/L is considered the “Action Level”. If you have 4pCi/L or higher, then the EPA recommends a radon mitigation program. The readings from the Watras house were 28.6 to 666.7 times that action level, very dangerous!

Unfortunately for the Watras family, they were then left in a pickle. There was no one with the government authority to mitigate the radon in the home, but it was too dangerous to live in. At the time, there were only two private companies in the US with any remediation experience. Both of those companies had experience in home construction, mostly with regard to cleaning up waste material from uranium milling sites. They did not have experience with remediating homes that were already built.

In April 1985, the Philadelphia Electric Company, which owned the plant, decided to undertake the remediation project themselves. In the first phase of remediation, they sealed cracks in the foundation, excavated the house down to the footings, which extend a little below the foundations of a home, and attached a protective membrane to one of the foundation walls. Phases two and three were inside the home- sealing cracks and installing a pipe that sent exhaust fumes through a roof vent. In phase four they realized they would need to essentially re-do the foundation of the home.

These are their results:

Today we use a system of suction points, pumps, and fans to reduce, remediate, or mitigate radon. We seal everything up to get the radon out of the house.

Now of course, we know much more about how to effectively mitigate radon, but back then it was a whole new thing. They were ultimately successful though and the Watras family was able to come back for the 4th of July that year. As a small bonus, because the crews had to put the excavated rocks and soil somewhere, they also came back to a freshly landscaped backyard.

On October 28, 1988, President Reagan signed the Indoor Radon Abatement Act into law. From the EPA archive, the law provided funding to help states set up radon mitigation programs, check the radon levels of schools, and assist with radon education and training.

Radon Today

We use lab-made radon isotopes for treating cancer, including lung cancer, ironically enough. We’ve learned over time that radon is a double-edged sword. On the one hand, from Cancer Research UK, it can be used to treat cancer that has spread to bones but not other organs. On the other hand, according to the EPA, it causes around 21,000 lung cancer deaths every year. And we’re still studying how changing radon levels in groundwater can help predict earthquakes (9).

One thing we do know: high levels of radon in the home are a big health risk. I encourage everyone to get a radon test every two years, per EPA recommendations. Get a test with us or pick one up at your local hardware store, but get tested and stay safe!

And, as always, thank you for reading!

Caption: In some places today radium is another way of saying glow in the dark. The radium cow pictured above is a perfectly safe figurine of the Kamdhenu Cow from India.

Works Cited

2. ‘Radium – a key element in early cancer treatment’ by Alan Dronsfield and Pete Ellis, published Feb 28, 2011.

3. By Physiographic provinces of Pennsylvania, Pennsylvania Geological Survey, 4th ser., Map 13, Pennsylvania Geological Survey of the PennDepCons&NatRes - manual transfer from en.wikipedia w:File:Map13.jpg, marked for BOT transfer, the commons helper seems to be broken, and TUSC login/validation also went awry., Public Domain,

4. NIST Physical Measurement Laboratory. 1927: NBS gold leaf electroscope.

5. Hot Times in “Radium Hospital”: The History of Radium Therapy at MSK by Matthew Tontonoz, published September 22nd, 2016.

6. Facts About Radon by Traci Pedersen, published July 31, 2018. Facts About Radon | Live Science

7. Environmental Radon: Occurrence, Control, and Health Hazards edited by Shyamal K. Majumdar et. all, published 1990. A Publication of the Pennsylvania Academy of Science.

9. Earthquake forecasting: A review of radon as seismic precursor by Anna Riggio and Marco Santulin, published June 2015. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Trieste, Italy.

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