Radon is a naturally occurring radioactive gas that leaks out of the ground due to the decay of the elements radium and uranium, natural substances that are found in the earth's crust. According to the Environmental Protection Agency, it can emanate from the soil into the water and air and is hazardous to human health.
The National Cancer Institute says that radon is the second leading cause of lung cancer, superseded only by cigarette smoking. The most common health complication resulting from radon exposure is bronchogenic lung cancer, including large and small cell carcinomas, adenocarcinomas and squamus cell carcinomas.
The United States Cancer Institute estimates that 15,000 to 22,000 people die each year in the United States due to radon-induced lung cancers.
The EPA says that radon can induce lung cancer when it is breathed in because it gives off tiny radioactive particles as it decays that damage healthy cells in the lung tissue. As these cells are damaged, they begin to replicate incorrectly, and cancer develops.
Other Respiratory Diseases
According to the National Cancer Institute, radon exposure can also cause a variety of other respiratory ailments. Many of these diseases are chronic and cannot be treated, only managed. These diseases include lesions in the lungs or respiratory tract (which can develop into cancer in some cases), emphysema (a condition that affect the sacs that hold oxygen in the lungs, making it difficult to breathe), pulmonary fibrosis (abnormal hardening of the lung tissue), silicosis (a condition that shortens breath and induces chronic coughing) and chronic interstitial pneumonia (abnormal fluid buildup in the lungs that can lead to shortness of breath and infection).
Effects on Chromosomes and DNA
Due to its radioactivity, radon can have harmful effects on reproductive tissue, on an embryo or fetus in a pregnant woman and on DNA. As radon decays, the alpha-radiation it emits can damage cellular DNA and cause problems with cellular reproduction. According to researchers at The Universiry of Minnesota School of Public Health, chromosomal abnormalities and DNA damage can occur in exposed individuals.
If a pregnant woman is exposed to radon and it is absorbed into her bloodstream, it will cross the placenta and enter the developing embryo or fetus. Exposure in early pregnancy can lead to miscarriage. In later pregnancy, the radon can cause brain damage leading to mental retardation in the baby.