Radon and Lung cancer

Radon and Lung cancer

 

• Radon is a substance known to cause cancer in humans (Group 1), according to the International Agency for Research on Cancer (IARC).
• Radon comes from rocks, soil, water, and building materials and can seep into indoor spaces. Since it can build up indoors, it's important to vent it outside to reduce exposure.
• Radon is a major cause of lung cancer. When we breathe in radon, it can lead to changes in lung cells, which increases the risk of cancer.
• Radon and smoking together greatly increase the risk of lung cancer. So if you smoke, quitting is especially important.

 

■  Environmental exposure

Radon is a radioactive gas created during the process of uranium decaying several times. It is colorless, odorless, and tasteless and exists everywhere on Earth. Radon occurs in rocks, soil, and building materials, so you can be exposed to it in your daily life. 85% of the radiation we are exposed to in our daily lives occurs naturally and can come from rocks, soil, and food intake. In homes built close to the ground, old buildings with lots of cracks in the floors and walls, and buildings with tight seals, radon concentration indoors can be high because it's hard for the radon to escape without proper ventilation. Radon from tall buildings mostly comes from the materials used in construction. If you are exposed to radon on a daily basis, it is important to provide good indoor ventilation, especially in spaces or underground spaces where indoor ventilation is difficult. To minimize exposure to radon, regular ventilation and checking of radon concentration are necessary.

 

■  Occupational exposure

Occupational exposure to radon mainly occurs in workers such as miners working in poorly ventilated underground spaces or near rock or soil. In modern times, occupations that work underground and in poorly ventilated work environments are at risk of radon exposure. Additionally, radon emitted from single-family homes, old buildings with many cracks in floors and walls, and high-rise buildings may also originate from building materials. Occupational exposure may occur due to the release of radon from radium and uranium in building materials such as gypsum board, brick, and concrete.

 

■   Radon and Lung cancer

Studies on underground miners exposed to high levels of radon have confirmed an increased risk of lung cancer. For example, studies on iron ore miners have shown a higher risk of lung cancer due to radon exposure. These findings highlight the importance of protecting miners from radon exposure to safeguard their health (1, 2).

According to research results in Europe, the lung cancer death rate due to residential radon exposure was found to be approximately 9%, and radon exposure can act as one of the main causes of lung cancer along with smoking. In particular, a recent study investigated the risk of lung cancer due to residential radon exposure in both non-smokers and smokers and reported that the risk of developing lung cancer increased to a statistically significant level (3, 4).

Radon's risk of contributing to lung cancer has been investigated through various studies. The 4th Committee on Biological Effects of Ionizing Radiation (BEIR VI committee) estimated the contribution of radon exposure to lung cancer to be 10-15% (5), and Brand et al. reported this rate to be 8% (6).

Overall, research indicates that indoor radon exposure plays a significant role in the development of lung cancer.

 

■  How to reduce exposure to radon

To minimize exposure to radon, it's essential to prevent radon gas from entering indoor spaces and to expel any radon that does enter outside through active ventilation systems.

<How to Reduce Exposure to Radon: generated by AI>

 

 

■   References

The content is primarily based on Casarett and Doull’s Toxicology 9th edition and the information on radon from EPA site (https://www.epa.gov/radon).

(1)     Tomasek, L., Rogel, A., Tirmarche, M., Mitton, N., & Laurier, D. (2008). Lung cancer in French and Czech uranium miners: radon-associated risk at low exposure rates and modifying effects of time since exposure and age at exposure. Radiat Res, 169(2), 125-137.

(2)     Vacquier, B., Rogel, A., Leuraud, K., Caer, S., Acker, A., & Laurier, D. (2009). Radon-associated lung cancer risk among French uranium miners: modifying factors of the exposure–risk relationship. Radiat Environ Biophys, 48(1), 1-9.

(3)     Darby, S., Hill, D., Auvinen, A., Barros-Dios, J., Baysson, H., Bochicchio, F., Deo, H., Falk, R., Forastiere, F., & Hakama, M. (2005). Radon in homes and risk of lung cancer: collaborative analysis of individual data from 13 European case-control studies. BMJ, 330(7485), 223.

(4)     Darby, S., Hill, D., Deo, H., Auvinen, A., Barros-Dios, J. M., Baysson, H., Bochicchio, F., Falk, R., Farchi, S., & Figueiras, A. (2006). Residential radon and lung cancer—detailed results of a collaborative analysis of individual data on 7148 persons with lung cancer and 14 208 persons without lung cancer from 13 epidemiologic studies in Europe. Scand J Work Environ Health, 1-84.

(5)     Council, N. R. (1999). Health effects of exposure to radon: BEIR VI. National Academies Press.

(6)     Brand, K. P., Zielinski, J. M., & Krewski, D. (2005). Residential radon in Canada: an uncertainty analysis of population and individual lung cancer risk. Risk Anal: An International Journal, 25(2), 253-269.