Thirdhand smoke dangerous to unborn babies lungs

Prenatal exposure to toxic components of a newly recognised category of tobacco smoke-known as 'thirdhand smoke'-can have as serious or an even more negative impact on an infants' lung development as postnatal or childhood exposure to smoke, according to a study by researchers at the Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center.

Thirdhand smoke is the newly formed toxins from tobacco smoke that remain on furniture, in cars, on clothing and on other surfaces-long after smokers have finished their cigarettes.

"Thirdhand smoke is a stealth toxin because it lingers on the surfaces in the homes, hotel rooms, casinos and cars used by smokers where children, the elderly and other vulnerable people may be exposed to the toxicants without realizing the dangers," said Virender Rehan, a principal investigator at LA BioMed and corresponding author of the study.

"Pregnant women should avoid homes and other places where thirdhand smoke is likely to be found to protect their unborn children against the potential damage these toxins can cause to the developing infants' lungs, he added.

Rehan, who has been researching the effects of smoking on lung development for more than a decade, said this is the first study to show the exposure to the constituents of thirdhand smoke is as damaging and, in some cases, more damaging than secondhand smoke or firsthand smoke.

"We looked at the mechanisms that drive normal lung development and found those mechanisms were clearly disrupted by thirdhand smoke," he said.

"Based on this, we can conclude that prenatal disruption of lung development can lead to asthma and other respiratory ailments that can last a lifetime," he added.

The study has been published in the American Journal of Physiology.