How 'third hand tobacco smoke' causes cancer revealed

A study has revealed about the potential cancer risk from tobacco smoke gases and particles deposited to surfaces and dust in the home in non-smokers, particularly young children.

Until now, the risks of this exposure known as 'third hand tobacco smoke' have been highly uncertain and not considered in public policy, but the latest findings indicate potentially severe long-term consequences, particularly to children, through non-dietary ingestion and dermal exposure to third hand smoke.

The study also demonstrates, for the first time, the widespread presence of tobacco related carcinogens in house dust, even in 'smoke-free' environments.

Lead investigator, Dr Jacqueline Hamilton, York's Wolfson Atmospheric Chemistry Laboratories, said that the risks of tobacco exposure do not end when a cigarette is extinguished and the risk should not be overlooked and its impact should be included in future educational programs and tobacco-related public health policies.

Another professor, Alastair Lewis, said that over 40 per cent of children have at least one smoking parent and whereas there is a general public awareness about the harms of second hand smoke, there is little knowledge about the dangers of third hand smoke and added carcinogenic materials can be passed from smokers to non-smokers during shared contact, for example between clothes and surfaces and also enter homes via airborne transport of cigarette smoke.

The researchers examined exposure to carcinogen N-nitrosamines and tobacco specific nitrosamines (TSNAs) in the dust samples, which are produced when nicotine deposits on indoor surfaces and then is released again to the gas phase or reacts with ozone, nitrous acid and other atmospheric oxidants and are classified as carcinogenic for humans.

This study is published in the journal Environment International.