Everyone is aware of the risks of smoking and also second-hand smoking. But what about third hand smoking, which refers to incinerated particles of tobacco that settle on surfaces?
Third hand smoking has only recently gained attention of researchers and health experts. Various studies have indicated the tobacco residues can remain on smoke-exposed clothes for months to years, potentially to return to the air where it can linger, especially in indoor environments.
A groupof researchers in a small study involving ten people found that tobacco smoke residues on clothing could elevate biomarkers associated with inflammation, mimicking the mechanisms of skin diseases. Though none of the volunteers developed skin diseases such as contact dermatitis and psoriasis, the researchers said that the harm done to the skin might well lead to health problems further down the line.
“Our third-hand smoke exposures were brief, did not cause skin irritation, and were unlikely to induce skin disease, nevertheless markers associated with early-stage activation of contact dermatitis, psoriasis and other skin conditions were elevated,” the researchers said.
The study was held in 10 healthy non-smokers aged between 22 and 45 years old, who were each asked to wear clothing affected by third-hand smoke for three hours. They were also asked to spend 15 minutes on a treadmill each hour, so that more third-hand smoke particles would be taken up through the skin through perspiration.
In the blood and urine samples, they found that biomarkers indicating oxidative damage to DNA were elevated. They also came across changes in blood protein levels. Apart from this, they found that the changes persisted up to 22 hours after exposure. No such changes were observed when the same 10 participants had worn clean clothing for the exercise, in another testing session.
The results suggest exposure to third-hand smoke echoes the kind of damage and activation of immune responses measured in cigarette smokers, the researchers report.
While none of the study participants showed changes in their skin or health, the early indicators are there and need further research – so far only very few studies have been done on how humans respond to third-hand smoke exposure, and none on exposure through the skin.
The researchers say that the skin might be at the greatest risk from third-hand smoke exposure as it is the largest organ. The researchers are hoping to conduct studies involving larger groups of people over a longer period of time, and they also want to examine the effects that electronic cigarettes have over the surrounding environment and population.
The research has been published in eBioMedicine