Lungs of people who had grown up with secondhand smoke had more ` ` holes '' Many ` ` holes '' -- less dense areas of lung -- are characteristic of emphysema . To investigate , Lovasi and her team looked at CT scans of the lungs of 1,781 nonsmoking 45- to 84-year-olds taking part in the Multi-Ethnic Study of Atherosclerosis ( MESA ) trial . Even though smoke - filled lungs functioned fine , there 's concern for future use . About 10 million people in the United States have emphysema , chronic disease .
Lungs of people who had grown up with secondhand smoke had more ` ` holes '' Many ` ` holes '' -- less dense areas of lung -- are characteristic of emphysema . Even though smoke - filled lungs functioned fine , there 's concern for future use . About 10 million people in the United States have emphysema , chronic disease .