The United States Environmental Protection Agency (EPA) classes radon as a carcinogen, meaning that radon poisoning can lead to cancer. It is the leading cause of lung cancer in non-smokers and the second leading cause in smokers.
Radon is recognized as a health risk, as it is not detectable and does not cause noticeable symptoms until its transformation into lung cancer.
This article will examine what radon poisoning is, its symptoms, how to test for the effects of radon, and how to minimize exposure.
- Radon is a naturally occurring radioactive element.
- It is a colorless, odorless and tasteless gas.
- Radon is found in the atmosphere but tends to accumulate in buildings.
- Radon can increase the risk of lung cancer, especially when combined with smoking.
- Before appropriate ventilation became mandatory, many miners developed lung cancer from radon exposure.
- There are a number of ways to reduce radon build-up in the home.
What is radon poisoning?
Radon is a gaseous element that results from the natural breakdown of radium.
Radon is a gas that occurs as the end product of radium decay, and radon poisoning takes place when large amounts enter the body and cause harmful physical changes.
It is a naturally occurring element that takes a gaseous form at standard temperatures and pressures. In fact, it is one of the densest substances that remains a gas under normal circumstances.
As a colorless, odorless, tasteless gas, radon is undetectable by human senses. Radon poisoning does not cause harmful, obvious symptoms in the same way that other radioactive substances might. Instead, radon exposure can lead to the development of lung cancer.
Radon occurs throughout most environments in very small quantities. However, it can amass in buildings. Radon accounts for the majority of most people's exposure to ionizing radiation.
Radon poisoning is symptomless.
This means that there is no meaningful indicator of having been exposed to radon. Not only can it not be smelt, tasted, or seen by the naked eye, it does not produce any effects in the body until causing the cellular changes that might lead to lung cancer.
This makes it especially important to take all necessary precautions to protect yourself from radon exposure, especially if you live in a Zone 1 area containing higher levels than the EPA deems safe.
If you start to cough up blood, feel chest pain, or experience difficulty breathing, visit a doctor immediately to rule out lung cancer.
Health effects of radon
Paradoxically, in the early 20th century, radon was touted by quacks as being beneficial to health. People could pay small sums of money to spend time in a "radiotorium" and be bombarded by radon.
Other companies attempted to add radon to water, but the short half-life of radon meant that it had disappeared by the time it reached them.
Radon was considered beneficial to health, but the role of radon in causing lung cancer changed public perception.
Its negative health implications were only discovered at a later date.
In the 1940s and 1950s, ventilation systems in mines were not widely implemented. Lung cancer in miners in the Czech Republic, South Australia, and Southwestern U.S. was attributed to radon inhalation. Despite the eventual realization of the hazards, radon-induced lung cancer in miners remained a significant hazard until the 1970s.
It is now known that the inhalation of large quantities of radon causes lung cancer. According to the EPA, radon is the second most common cause of lung cancer, after smoking.
Radon causes 21,000 lung cancer deaths per year in the U.S. About 2,900 of those deaths occur in people who have never smoked.
Diagnosis of radon poisoning
There is currently no test to diagnose or identify past exposure to radon.
With the lack of available testing and noticeable symptoms, it is doubly important to minimize exposure to radon.
Where is radon found?
Radon emanates from a range of natural sources, including:
- uranium ores
- phosphate rock
- igneous and metamorphic rocks, such as granite
- more common rocks such as limestone, to a lesser extent
It is not just natural rock that contains radon. Man-made structures can also be responsible for radon poisoning.
Radon tends to enter buildings at their lowest point. It often makes its way in through splits in foundations, cracks in walls, gaps around pipes, cavities inside walls and the water supply. The gas is likely to accumulate in airtight buildings that are not well-ventilated.
Levels vary a great deal between locations and, although the half-life of radon is less than 4 days, it can build up in high concentrations, especially in areas of low elevation such as basements or mine shafts.
It is worth noting that two adjacent homes and even two adjacent rooms can vary significantly in their levels of radon. This helpful resource from the EPA shows the areas of the U.S. with the highest natural levels.
Iowa has the highest percentage of homes scoring above a safe radon level, with 71.6 percent of homes potentially affected. The high levels of radon in Iowa are the result of ancient glaciers that have ground down granite rocks over and deposited them in the form of soil.
Radon has also been found in some spring water and hot springs.
Radon risks at home
There are some difficulties in assessing the exact risks of radon in the home. Most studies have used data from miners, who will have had far more exposure to radon than is likely in any building.
The biggest cause of lung cancer is smoking, and this can confuse identification of radon as a cause of cancer because even non-smokers may have been exposed to second-hand smoke.
A combination of radon and cigarette smoke could, potentially, be more harmful than either on an individual basis.
Some researchers believe that the risk of cancer from radon without exposure to cigarette smoke is so small as to be almost insignificant.
Others, however, believe the risks presented to lung health by radon are understated and deserve more attention.
How to minimize radon risks
Some estimate that 1 in 15 homes in the U.S. has elevated levels of radon. Radon test kits are widely available and are generally cheap or even free. Click here to choose from a range of testing kits online.
Radon kits include a collector to be left in the lowest habited room of the house for 2 to 7 days. This can then be sent off to a laboratory for evaluation.
A radon testing kit can help bring attention to increase levels in the home.
If the radon readings are high, there are a number of ways to deal with the issue. The most common methods include:
- Sub-slab depressurization, or soil suction: This consists of a vent pipe system and a fan that pulls radon from under the house, venting it to the outside.
- Improving ventilation: It is also important to avoid moving radon from lower floors to the rest of the home.
- Radon sump system: A sump is an under-floor cavity into which a pipe is inserted. A fan pulls air and radon up and away from the home.
- Positive pressurization: These systems constantly blow fresh filtered air into the home to clear out radon.
It is worth noting that simply making your home airtight has not been proven to limit radon levels unless other measures, like the ones above, have also been implemented.
Although studies have demonstrated the link between radon and cancer, its implications for health at the levels found in the home are still up for debate, with smoking making conclusions difficult to draw.
However, it is better to be safe than sorry, and all homes can be adapted if required.