Children are most vulnerable to third-hand smoke pollutants that settle indoors when tobacco is smoked, said health experts on Thursday, ahead of World No Tobacco Day.

World No Tobacco Day is observed every year on May 31 to raise awareness about the health risks of using tobacco.

Thirdhand smoke contains more than 250 residual chemicals including nicotine and cancer-causing substances such as formaldehyde, and naphthalene. It builds up on surfaces over time and can get embedded in clothing, furniture, drapes, bedding, and carpets.

“Children are most vulnerable to thirdhand smoke because they tend to touch surfaces, and often their mouths, resulting in skin exposure and ingestion of these residues,” Lancelot Mark Pinto, from P. D. Hinduja Hospital & MRC, Mumbai, told IANS.

“The only way to prevent such exposure is by completely banning indoor smoking, and insisting on keeping a radius outside buildings and homes smoke-free,” added Lancelot, Consultant Pulmonologist and Epidemiologist at Hinduja.

Thirdhand smoke is a hidden danger, lingering in furniture, walls, and clothing long after a cigarette is extinguished. The residue can remain for weeks, months, or even years.

“Vulnerable groups include infants, children, and those with respiratory conditions, as they are more likely to come into contact with these contaminated surfaces and inhale harmful residues,” Ishan Capoor, pulmonologist and respiratory medicine, Narayana Health City, Bengaluru, told IANS.

“This exposure can lead to respiratory issues, developmental problems, and an increased risk of cancer,” he added.

To prevent third-hand smoke exposure, ensure that smoking is strictly prohibited indoors and in vehicles. Regularly clean surfaces and fabrics, and encourage smokers to quit or at least to smoke outside and away from others. Awareness and proactive measures are essential to protect the health of those most at risk.”

In addition to children, Srinath Bharadwaj, Medical Oncologist at Apollo Cancer Centre, Jubilee Hills, Hyderabad, told IANS that it may also harm pets in the house.

“Our furry friends usually groom by licking their fur. If that fur is coated with smoke residue, they ingest carcinogens and toxins on top of the ones their lungs take in,” he said.

The experts called on businesses, communities, and individuals to take action to help prevent thirdhand smoke exposure by not allowing smoking indoors. Smoking in front of an open window does not prevent thirdhand smoke exposure.

“The best way is to quit smoking and stay safe and keep your family safe,” they noted.