Warning Against Thirdhand Smoke

Smoking residues present a health risk long after the cigarette has been extinguished, according to new research published in the Journal of Exposure Science and Environmental Epidemiology.

As part of a study on thirdhand smoke, which is the presence of toxic tobacco byproducts that remain on surfaces such as furniture, decor, walls and floors, scientists tested the surfaces in smoking households where children reside.

According to lead author Ashley Merianos, they found nicotine on surfaces in all of the children’s homes and detected the presence of a tobacco-specific carcinogen (NNK) in nearly half of the homes, she says. 

The study reported that the NNK levels on surfaces and in vacuumed dust were similar, which Merianos says indicates that surfaces and dust can be similar reservoirs and sources of thirdhand smoke exposure for children.

“This is critically important and concerning since NNK is considered the most potent carcinogen for tobacco-induced cancers,” said Merianos, an associate professor in UC’s School of Human Services, in a statement.

Additional findings include:

• Children living in lower income households had higher levels of NNK and nicotine found on home surfaces.
• Children living in homes that did not ban indoor smoking had higher levels of NNK and nicotine found on surfaces.

Merianos says that NNK and nicotine were still detected in homes with voluntary indoor smoking bans, which highlights the persistence of thirdhand smoke pollutants on surfaces in children’s homes.

“This research highlights that home smoking bans do not fully protect children and their families from the dangers of tobacco,” she adds.