ENVIRONMENTAL POLLUTANTS | Radon

摘要: Radon gas is the most important source of natural radioactivity. It a radioactive noble that emanates from ground. concentrations in outdoor air are low, but underground mines or inside houses radon can reach high levels. The biologic effects mostly due to its decay products. These solid heavy metal isotopes themselves radioactive. They be deposited on bronchial epithelium, where they emit ionizing radiation form α -particles. Alpha effectively cause permanent damage DNA and eventually lead cancer. Epidemiological studies have given conclusive evidence carcinogenic humans lung first were performed miners exposed levels radon. Later general population showed cancer even at lower found houses. This indoor exposure currently estimated contribute 5–10% deaths.