How do carcinogens in cigarette smoke cause cancer?
n a study of cancer myths, 40 percent of people agreed that city air pollution was a bigger risk for lung cancer than was smoking. Pollution certainly may contribute to some cases of lung cancer, but not anywhere near the number caused by smoking. Yet the idea that chemicals in the environment are a major cause of cancer persists. Researchers estimate that cancer-causing chemicals (carcinogens) in the environment cause fewer than 5 percent of cancer deaths in the United States. Most cancers are believed to be caused by lifestyle choices, such as what you eat, whether you maintain a healthy weight and whether you smoke. So why do some people still believe their environment is a major cause of cancer? Here’s an in-depth look at the issue. Why is there so much confusion over whether certain chemicals are carcinogens? Most cancers take years to develop, making it difficult to determine if a chemical exposure today will cause cancer in the future. Tumors usually develop for 15 to 20 years b
