In some cases, the nonsmoker can be allergic to the smoke. Signs of an allergic reaction can include coughing, sneezing, difficulty breathing, and headaches. There are also a number of long-term effects of secondhand smoke. In 1992, the Environmental Protection Agency classified secondhand smoke as a Group A carcinogen, the most dangerous of the cancer causing agents. One of the most talked about side effects is lung cancer.
Passive smoking increases the chance of a nonsmoker getting lung cancer by twenty-six percent.
Lung cancer, as a result of secondhand smoke, is responsible for the deaths of 4,000 nonsmokers a year. Secondhand smoke also contributes to the heart disease. The American Heart Association also estimates that 40,000 die each year from heart and blood vessel diseases caused by secondhand smoke. According to the AHA the risk of heart disease increases thirty percent among those exposed to secondhand smoke at home or work. Passive smoking lowers one's resistance to lower respirator diseases such as bronchitis, pneumonia, and bronchiolitis.