Lungs of adults who had grown up with secondhand smoke had more ` ` . '' Many ` ` holes '' -- less dense areas of lung -- are characteristic of emphysema . Even though smoke - filled lungs functioned fine , there 's risk for future health . About 10 million people in the United States have emphysema , chronic disease .
Lungs of adults who had grown up with secondhand smoke had more `` holes '' Many `` holes '' -- less dense areas of lung -- are characteristic of emphysema . Even though smoke-exposed lungs functioned fine , there 's concern for future health . About 24 million people in the United States have emphysema , chronic bronchitis .