Ongoing lung tissue damage and impaired lung function many years after exposure to secondhand tobacco smoke in individuals who never smoked tobacco cigarettes

The World Health Organization estimates there are 800,000 deaths related to secondhand smoke exposure each year. A large body of scientific evidence has demonstrated secondhand smoke exposure is a risk factor for pulmonary diseases, including chronic obstructive lung disease (COPD). However, we don’t know the long-term health consequences from excessive and prolonged secondhand smoke exposure, which occurred many years ago, on lung damage and function.  

In a new study, Dr. Jelena Mustra Rakic and colleagues discovered ongoing lung tissue damage and impaired lung function many years after exposure to secondhand tobacco smoke in individuals who never smoked tobacco cigarettes. They evaluated nearly 300 people, most of whom were flight-attendants heavily exposed to cabin secondhand smoke before smoking was banned on all domestic and international flights in 1995. 

The study found that those people with occupational exposure to secondhand smoke had greater lung damage as indicated by elevated elastin degradation, beyond what is expected from the aging process, compared to those without secondhand smoke exposure. These findings suggest that intense exposure to secondhand tobacco smoke, even though it occurred many years ago, could instigate a self-propagating process of lung damage and ongoing lung function decline. This study is the first one providing molecular evidence of lung damage from past remote exposure to secondhand smoke. The results highlight the importance of asking about a history of environmental or occupational exposure to secondhand tobacco smoke in our aging patient populations.  

This study was funded by grants from the Flight Attendant Medical Research Institute (FAMRI) to UCSF FAMRI Bland Lane Center of Excellence on Secondhand Smoke (Dr. Rita Redberg), San Francisco Veterans Affairs Healthcare System (Dr. Mehrdad Arjomandi), and Icahn School of Medicine at Mount Sinai-St. Luke's-Roosevelt (Dr. Gerard Turino).