He said recent research had focused on specifying the effect of residential radon on lung cancer risk. "In these studies, scientists measure radon levels in the homes of people who have lung cancer and compare them to the levels of radon in the homes of people who have not developed lung cancer."
How radon enters the body
Strydom explained that radon is formed through the decay of uranium. "Radon decays to a series of radioactive atoms called radon daughter products. These are metal atoms that attach themselves to aerosol particles in the air e.g cigarette smoke."
After inhalation of the particles, he said, these atoms adhere to the respiratory tract, especially in the deep lung area, where they subsequently decay radioactively.
"This means that they eject high energy alpha rays directly into the lung cells, causing radiation damage to the cell DNA. The cells repair the damage, but it becomes irreparable if the exposure is chronic, e.g through a lifetime. The damaged DNA is the start of cancer."
How radon enters our homes
Radon is found in small quantities in all rocks and soil and is also present in air, water and building materials like bricks and mortar.
Strydom said when uranium occurs in e.g. soil, the radon atoms formed in the soil pores diffuse to the surface of the soil and escapes into the atmosphere.
"From there, the gas may penetrate into homes through natural ventilation. Radon will also intrude into a home from the subsoil on which the house is built, permeating through the floor slab and floor openings."
In America and Europe people regularly test their houses for radon exposure, but this is not the case in South Africa.
Purpose and Structure of This Guide Health care providers play a key role in reducing their patients’ exposure to unecessary radiation. With the rate of medical imaging and related radiation exposure increasing, it is even more crucial to reduce radiation exposure from other sources, including radon. Because radon is a leading environmental cause of cancer mortality in the United States,1 it is imperative that patients be informed about the health risks of protracted radon exposure and the simple steps they can take to reduce their exposure.
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