Residential Radon Gas: A risk Factor for Lung and Skin Cancer
Radon is a chemical element having an atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas. Being a noble gas, radon is chemically not very reactive. It is the densest of all noble gases.
It is formed during the natural breakdown of uranium in soil, rock and water. Levels of radon in the soil can vary greatly from one place to another. Radon can also be present in groundwater.
Residential radon gas -
Radon, which exits in the ground, can seep into our homes through cracks and holes in the foundation. Radon is one of the densest gases at room temperature. It can sometimes accumulate and reach levels that can lead to health risks. Since it is a gas with no smell, taste or color, it is impossible to detect it with the senses.
Radon can seep into buildings through various openings, including cracks in concrete slab or foundation walls, drains, crawlspaces, joints, openings around vent pipes, service lines and pipe fittings.
Outdoor radon levels are usually very low. Radon disperses in the ambient air fast and therefore does not cause health problems. It is the level of residential radon gas that may be quite harmful.
What is the safe level of radon gas? -
A safe level of radon gas is no radon gas. The lower the radon levels in your home, the lower your family’s risk of lung cancer. The World Health Organization experts recommend that countries should adopt reference levels of the gas of 100 Bq/m3 (Becquerel per cubic metre), which is equal to 2.7 pCi/L (Picocuries per liter of air). The WHO measures in Becquerels. It takes 37 Bq/m3 to equal 1 pCi/L.
But this level cannot be implemented under the prevailing country-specific conditions. Depending upon the country, the acceptable radon levels vary. Notwithstanding country specific conditions, the WHO recommends that the reference level should not exceed 300 Bq/m3.
Lung cancer risk rises 16% per 100 Bq/m3 increase in radon exposure above the reference level.
Residential radon and lung cancer -
Studies show that radon is the primary cause of lung cancer among people, who have never smoked. However, the absolute numbers of radon-induced lung cancers are much larger in people who smoke, or who have smoked in the past, due to a strong combined effect of smoking and radon.
A meta-analysis of residential exposure to radon gas and lung cancer shows that although no definitive conclusions may be drawn, the results suggest a dose–response relation between residential exposure to radon and the risk of lung cancer. Hence the experts support the need to develop strategies to reduce human exposure to radon.
Meta-analyses previously conducted with different methods found significantly increased risks of lung cancer of 6–35% in participants exposed to residential radon at levels of 100–150 Bq/m3. These results show a consistent pattern of risk related to indoor exposure to radon, although the magnitude of the risk seems to be low.
Residential radon and skin cancer –
Undisputedly, residential radon exposure is risk factor for developing lung cancer. But a new study shows that it is also a risk factor for malignant skin cancer (malignant melanoma).
The study analyzed 1,900 deaths due to malignant melanoma which occurred throughout Switzerland between 2000 and 2008 in people aged 20 years and above. The residential radon exposure was modeled on the basis of 45,000 measurements and accounted for the housing's characteristics and the geological conditions of the area.
The study shows that, when radon decays, radioactive alpha particles not only destroy lung tissue but can also affect the skin. This has rarely been researched in the past. This needs to be substantiated further by more studies.
It is noteworthy that Switzerland has the third highest incidence rate of malignant skin cancer worldwide, which places it far above the central European average.
The soil under and around our houses is by far the largest source of radon gas. It is also present in well water, building materials, public water supplies and outdoor air. Since radon is an unstable gas, it breaks down and dissipates quickly in the open air. Dangerous levels of radon can accumulate inside a house.
Radon is a cancer causing radioactive gas, which is colorless, odorless and tasteless. And that is why it cannot be detected by our senses. It has been found that children are more sensitive to the gas. It is the leading cause of lung cancer among non-smokers. Recently, it has been shown in a study that residential radon exposure is also a risk for malignant skin cancer (malignant melanoma).
- Meta-analysis of residential exposure to radon gas and lung cancer
Maria Pavia, Aida Bianco, Claudia Pileggi, & Italo F. Angelillo
Bulletin of the World Health Organization 2003; 81:732-738
- Swiss Tropical and Public Health Institute. "Radon increases risk for malignant skin cancer." ScienceDaily. ScienceDaily, 16 June 2017.