Researchers have discovered for the first time that passive smoking or second-hand smoking causes structural damage to the lungs.
The discovery was made using a novel MRI technique by researchers at the University of Virginia School of Medicine in Charlottesville and The Children’s Hospital of Philadelphia in Pennsylvania under the leadership of Dr. Chengbo Wang.
“It’s long been hypothesized that prolonged exposure to second-hand smoke may cause physical damage to the lungs, but previous methods of analyzing lung changes were not sensitive enough to detect it,” said Dr. Wang.
Second-hand smoke has emerged as a public health threat in recent years. It has been classified as a carcinogen by the Environmental Protection Agency and has been linked to heart disease, lung cancer and a number of respiratory ailments, including asthma and chronic bronchitis.
Children are particularly susceptible to the harmful effects of second-hand smoke.
Dr. Wang and colleagues used long-time-scale, global helium-3 diffusion magnetic resonance imaging (MRI) to study the lungs of 43 volunteers, including seven current and former smokers and 36 non-smokers, 18 of whom had a high level of exposure to second-hand smoke.
Helium-3 diffusion MRI differs from conventional MRI in that the patient inhales a specially prepared helium gas prior to imaging, and the scanner is adjusted to collect images showing this helium gas in tissue. MR measures how far the helium atoms move, or diffuse, inside the lungs during a specific time period — 1.5 seconds in this study.