Doctors believe that second-hand smoke may cause lung cancer in people who do not smoke. Nonsmokers often breathe in the smoke from other people’s cigarettes. This is second-hand smoke. The U.S. Environmental Protection Agency(美国环保局) reports that about fifty-three thousand people die in America each year as a result of exposure to second-hand smoke.It is harder for children to avoid second-hand smoke. In America, nine million children under the age of five live in homes with at least one smoker. Research shows that these children are sick more often than the children who live in homes where no one smokes. The damaging effects of second-hand smoke on children also continue as they grow up. The children of smokers are more than twice as likely to develop lung cancer when they are adults as the children of nonsmokers. The risk is even higher for the children who live in homes where both parents smoke. People are becoming very aware of the danger of second-hand smoke. As a result,they have passed laws that prohibit from smoking in many public places. Currently, 45 states in the United States have laws that restrict, or limit smoking. The most well-known law doesn’t allow people to smoke on short native airline flights, i.e. flights within the country.
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B:2