Heart palpitations can be triggered by stress, exercise, medication or, rarely, a medical condition. Although heart palpitations can be worrisome, they're usually harmless. In rare cases, heart palpitations can be a symptom of a more serious heart condition, such as an irregular heartbeat (arrhythmia), that may require treatment. Symptoms.
Long-term exposure to radon can lead to lung cancer, the only cancer proven to be associated with inhaling radon. There has been a suggestion of increased risk of leukemia associated with radon exposure in adults and children; however, the evidence is not conclusive.
Exposure to radon is the second leading cause of lung cancer in the United States, after smoking. Radon gas occurs naturally. It forms when uranium breaks down to radium, which in turn breaks down to form radon. As radon decays, it releases radioactive byproducts that are inhaled and can cause lung cancer.