Lung Cancer Causes – Radon Gas

Lung Cancer Causes – Radon Gas

Radon is known to accumulate in closed spaces. An increased level is seen in underground rock mines, especially those containing uranium. This concentration is mainly caused by gas entering directly from the ore, but radon can also be brought into the mine when it is dissolved in water. For indoor radon, diffusion from subsoil remains the most important source. Other additional, less significant sources include building materials and radon dissolved in water. Within the structure of a building, radon concentrations are highest in the basement, due to the proximity to the subsoil.4People residing near uranium mines have a higher radon exposure. Indoor radon levels vary throughout the United States, depending on local conditions.

Exposure to radon gas is considered to be the leading cause of lung cancer in non-smokers. Although radon occurs naturally in an outdoor environment, concentrated levels of the gas associated with uranium deposits can be harmful. In particular, people that live or work in an environment that is contaminated with a high concentration of radon have been linked to a risk of lung cancer.

Radon is the 2nd leading cause of lung cancer, causing 12% of lung cancer deaths.Radon is a gas found in soil that can leak under building through gaps in the foundation or insulation. Radon is in 1 out of every 15 homes in Illinois. Smoking and radon exposure together greatly increases your risk.

Radon, a colourless and odourless gas emitted through soil, is believed to be responsible for 16 per cent of lung cancer deaths in the country each year, making it the second-leading cause of lung cancer fatalities after tobacco use, says the Canadian Cancer Society. It's estimated that 3,000 Canadians die from lung cancer caused by radon annually.

Researchers have focused on the relationship between lung cancer risk and residential radon exposure and its effects. Comparisons of radon gas levels have been made between homes where residents have and have not developed lung cancer.

Radon exposure increases your risk of developing lung cancer. It is the second leading cause of lung cancer after smoking.

Your risk of cancer depends on several factors:

• the level of radon in your house
• how long you are exposed
• whether you smoke (exposure to radon and tobacco use together can significantly increase your risk of lung cancer)
  
  

Radon is classified as a human carcinogen by various US agencies, including the National Toxicology Program (NTP), the International Agency for Research on Cancer (IARC), and the Agency for Toxic Substances and Disease Registry (ATSDR). In addition to the scientific evidence described above, there is strong epidemiologic evidence to support the causal association between radon and lung cancer. The initial evidence emerged from the observation that many underground miners died of lung cancer. This finding led to the detailed study of various cohorts in miners across many countries, including Czechoslovakia, France, Australia, the United States, Canada, Sweden, and China. Although most of these were in uranium mines, the studies from the last 3 countries involved other metal mines. An increased risk of lung cancer from radon exposure was demonstrated among these cohorts. The relative risk (RR) was found to be time-dependent, and decreased when more time had elapsed since last exposure. Long-term exposure yielded a greater risk than did short-term exposure, irrespective of the rate of exposure. Data from these miner studies led to an interest in the risks associated with indoor radon exposure, and triggered a number of case-control studies that evaluated residential radon exposure. These studies enrolled people from the general population who had been exposed to indoor radon, and compared patients with lung cancer to lung cancer–free controls. 

 

Yet a national survey commissioned by the society found that only one in three respondents was aware of health issues concerning radon gas, while about the same proportion knew the radioactive gas could be "very harmful." About one-quarter of the 1,238 respondents had no idea it posed a health risk at all.

Research led by the National Institute of Environmental Health Sciences studied residential radon gas exposure among women (413 with lung cancer and 614 without lung cancer) that lived in their homes for at least 20 years. Data was recorded concerning various factors such as radon gas level measurement in the participants’ homes, information about the homes, and observation of lung cancer tissues. The outcome of this study indicated a link between lung cancer incidence and high rates of continuous radon gas exposure. Other research has been conducted throughout the United States and other regions of the world. The majority of research likewise shows a relationship between residential radon gas exposure and high incidence of lung cancer; although there are cases where there have been inconsistencies in some studies. Discrepancies may be due to variations in radon level in different homes, difficulty in radon gas measurements over long periods of time, and varying sizes of groups that participate in studies.

If the radon level in your home is above the Canadian guideline of 200 becquerels/metre³, you need to reduce it. The higher the radon level in your home, the sooner it needs to be reduced.

More accurate ways to measure radon gas exposure are being developed. Researchers used a new method for measuring indoor radon gas levels during a study conducted in Sweden in 2002. Scientists used objects (i.e. glass, mirror, etc.) that had remained present in a home for an extended period of time (15 or 20 years) to measure radon levels. This and earlier methods of radon gas measurement have shown a relationship between long-term, high level radon gas exposure and lung cancer.

One of these solutions is a commonly-used method known as sub-slab depressurization. A pipe is installed through the foundation floor and is piped to the outside with a small fan attached, which draws the radon from under the house and pushes it back outside, before it can enter your home. This solution can reduce the radon level in a home by more than 90%.