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.
Over time, exposure to radon can cause lung cancer. Radon causes about 21,000 lung cancer deaths each year in the U.S. It is the second leading cause of lung cancer, after tobacco smoking. People who smoke have an even higher risk of lung cancer from radon exposure than people who don't smoke. Radon exposure doesn't cause symptoms.