What Can Cause It?
Different carcinogens, particularly those from smoke, are the leading causes of lung cancer. Additional components such as radiation and viruses can also cause the disease. Basically, tissues exposed to large amounts of these factors suffer damage to the bronchi and ultimately change the DNA itself. This makes the cell growth control factors fail, leading to cancer.
According to a 2006 study conducted by the University of Oxford, 90 percent of lung cancer deaths are attributed directly to smoke, most notably tobacco smoke. Over the course of a person's lifetime, smokers have a 14.4 percent chance of developing lung cancer, while nonsmokers only have a 1.3 percent chance.
The United States Environmental Protection Agency has found that radon gas is responsible for the second-highest rate of cancer in the country. Approximately one in 15 homes has levels above the recommended guidelines. Overall, radon gas has been shown to raise lung cancer risk by 50 percent in individuals exposed to the toxin.
Other factors also contribute to major levels of lung cancer throughout the world. Roughly three percent of all lung cancer deaths stem from asbestos exposure. Likewise, viruses such as the human papillomavirus have been shown to contribute to high levels of lung cancer.