Radon Therapy

by Brian Dunning
December 21, 2021

In what seems like a throwback to the days when quack medical products included radium, causing people's jaws to fall off from cancer, some people are once again turning to a carcinogenic radioactive element for their health. This time it's not radium but radon, an alpha particle emitter, and second only to smoking as a cause of deaths from lung cancer. The benefit, they say, is pain relief, or treatment of high blood pressure, or — in the ultimate irony — treating cancer. It is not an approved therapy in the United States (though it is in some other countries), so the playing field is wide open for anyone who wants to sell it, and anyone who wants to try using it.

Radon therapy is given in two ways. First, most common in the United States, is for it to be inhaled, usually in abandoned mine tunnels, as radon is constantly being produced by the decay of heavier radioactive elements in the rock. Second, most common in Europe and Japan, is for it to be given as a bath in warm water infused with radon gas. It is absorbed through the skin and into the bloodstream, and can be found in the air the patient exhales quite quickly. So both methods get radon into the lungs quite effectively, which is why radon's primary effect on the body is to cause lung cancer. However, the belief is that the alpha particles bombarding the lung tissue will also produce some kind of beneficial effect.

The effect that the believers are hoping for is called radiation hormesis, which is a complex topic, and was discussed in detail in Skeptoid episode #539, so listen to that one if you'd like to know more about it. But the short version is that some people believe extremely small amounts of radiation are medically helpful rather than harmful. They often compare it to the way a vaccine works: you can challenge your body to respond to an attack, and it will strengthen the body's defenses. But vaccines work because they stimulate the production of immune cells designed to fight a specific disease. Radiation is not a disease that your immune system fights; radiation is a bombardment of tiny particles that destroy your DNA. There is no immune cell that defends against that; and a body cannot be strengthened against it.

Radiation hormesis has been studied extensively, due to high consumer interest in its potential. The data is inconclusive, with results all over the place. The reason is because the results are all basically below the noise level. Researchers have to look for health effects from radiation levels that are at or near the background noise level, so with data that's essentially random noise, no trends can be drawn. So if there is a positive effect, it's so small that it's statistically undetectable.

However, unlike radiation hormesis which uses low doses of radiation, radon spas expose the patients to high levels. Skeptoid #698 was all about radon gas that may be present in your home, and whether you need to worry about it. The short answer is that you do, at least enough to get tested. The Environmental Protection Agency established 4 pCi/L (picocuries per liter) as the action level, meaning that if you have more than that in the air of your home, you need to take steps to mitigate it, as that means you have a real chance of getting lung cancer. But in the radon spas located in mines in the United States, levels are up to 1600 pCi/L; 400 times the EPA action level.

Let's do a direct comparison. A typical recommended course in a radon spa is 32 hours. Since being in there gives you up to 400 times the exposure level of a house at the EPA action level, a trip to the radon spa is like spending 12,800 hours in such a house. Since the average American spends about 60% of their time in their house, that many hours is like living there for two and a half years. But that's only one treatment; most radon spa customers are repeat visitors; how often they come is all over the map. Each time they take such a treatment, it's the equivalent of two and a half years in a house the EPA says is too dangerous to live in.

I'll leave it to you to guess whether any medical researcher would recommend such treatments just to obtain the completely uncertain and undetectable benefits some believe it might provide, in addition to the guaranteed lung cancer risk.

And yet, people keep going, and they keep reporting pain relief. So what's going on?

For four years beginning in 2007, anthropologist Dr. Barbara Erickson visited various radon spas in the United States and Europe with a population of people suffering from arthritis pain, to see and how people used these facilities, and to learn about the facilities themselves. Her paper was published in the journal Dose-Response as a study of the human dimension of radon therapy. Dose-Response is a journal noted for its friendliness toward radiation hormesis, so most of the published research on radon therapy is found there. Her paper made a number of interesting observations:

• First, the difference between how radon therapy is provided in the United States and in Europe is dramatic. In Europe, it's typically sold at high-end spas, where clients spend the weekend in luxury suites eating gourmet meals, swimming in radon pools, and basking in comfortable radon tunnels; all under the watchful eye of doctors, and often paid for by insurance or national health plans. The experience in the United States is the polar opposite. There is no insurance coverage and so no way to support expensive facilities or pay doctors, thus the industry has been driven underground, both figuratively and literally. Radon therapy here is in old mine tunnels, completely rustic with little or no facilities, and no lodging other than campgrounds outside. There are no doctors and nothing in writing calling it a treatment or cure for anything, as any such claims would be illegal.
  
  
• Chronic pain tends to be the reason most clients seek out radon therapy.
  
  
• The industry tends to prey on the elderly, according to Erickson's observation of clients. Elderly people are more likely to have chronic pain conditions such as those they believe radon therapy will treat, and they are often on fixed incomes and their medical budgets are often already maxed out. Interestingly, and fortunately, the elderly are also least likely to have to worry about long term lung cancer caused by their radon exposure; so in a sense, radon therapy can be viewed as relatively harmless, the older a client is.
  
  
• The Big Pharma conspiracy theory is prominent among radon therapy clients in the United States. They believe that its lack of profit potential is the reason why it's not approved as a medical treatment and covered by insurance. But as we discussed in the full Skeptoid episode #589 on the Big Pharma conspiracy theory, this is completely nonsensical as demonstrated by the European radon spas, which charge high fees and offer a luxury environment, for a treatment that costs almost nothing to provide. The treatment can be sold in an extraordinarily profitable manner, by anyone who wants to. Logically, if it could obtain FDA approval, American providers would snap up radon therapy, jack up the price, and license it to protect against competition from medical outsiders like the mine owners who offer it now.

In a separate article, I think Dr. Erickson's abstract included a great succinct explanation for why these clients keep going:

...American health mine clients adjust or replace "toxic models" of radon with new kinds of explanatory models that allow radon to be redefined as a healing substance. The manner of this adjustment varies according to peoples' individual needs, their own preexisting cultural models and experiences, and their individual personalities; the source of authoritative knowledge accepted by each person is a strong influence. Through these altered explanatory models, mine clients are able to view their use of radon therapy as a rational course of action.

Put all of that together and it means there are plenty of reasons for fallible humans to try radon therapy — and even to keep going back for more — regardless of whether it actually works or not. But that's really the operative question here, so let's have a look at what little research exists to see what it says. And it is indeed a little research; very few studies are conducted in a field that requires subjecting humans to high doses of carcinogenic radiation. Thus the studies that do exist are mostly observational studies of the people who are already going for radon therapy, so important study components like blinding and control groups are often not included. And indeed, many of the studies are conducted by the spas themselves, predictably giving positive results, as determined by reduced usage of pain medications after six months. Every single study I found had either unacceptable conflicts of interest or worthless methodology.

Most of the studies I found used baths located at the European radon spas as the delivery method, and all used existing clients of these spas as the test subjects. When a control group was used, the sham placebo treatment was a carbon dioxide bath — basically bathing in warm soda water — which many of these spas also offer as a regular therapy. Regular clients would be familiar with both: a carbon dioxide bath is fizzy, while a radon bath is not. To them it's quite obvious which one they're in, so for the study authors to say that their test was randomized and blinded is not very persuasive. In one study, many patients declined to participate after being told that if they were randomized into the carbon dioxide group they wouldn't get to have the radon baths they wanted; in another study, the groups were switched halfway through so that all study participants got both bath types.

Studies coming out of Japan tend to use the inhalation method, which is much easier to make blinded because radon is colorless and odorless and you can't tell if it's in the air you breathe. One study I read (again, published in our old friend Dose-Response) tested it as a treatment for cancer; they had one patient for each of four types of cancer, all four of whom had also received conventional cancer treatment. Although the paper frankly admits in each case study that there's no way to tell if the improvement was from the conventional cancer treatment or from the radon, its conclusion still manages find that the radon appears to be an effective cancer treatment.

So here's where I'm coming down on radon therapy, pending additional information. Nearly all the published work finding that it's beneficial comes from low quality studies published in a journal that's basically dedicated to the promotion of radiation hormesis, a fringe idea not supported by most scientists and not supported by good evidence. All radon therapy is dangerous and definitely does increase your risk of lung cancer, though not enormously, and on a timescale that is probably not relevant for most elderly people. It's certainly not as bad as drinking radium 100 years ago, but it's cut from the same cloth. Its most significant effect is to transfer money from your pocket to the pockets of those who sell it. So at this point, the Skeptoid recommendation is to pass.

By Brian Dunning
Follow @BrianDunning