A study, published in the Proceedings of the National Academy of Sciences (PNAS) suggested that the residual nicotine from tobacco smoke reacts with ambient nitrous acid it forms carcinogenic tobacco-specific nitrosamines, or TSNAs.

Berkeley scientists in the US initiated lab tests and discovered significant levels of toxins on smoke-exposed material.

In additions, the study also explains that when a cigarette burns, nicotine is released in the form of a vapor that collects and condenses on indoor surfaces such as walls, carpeting, drapes and furniture, where it can linger for months.

The nicotine from the residue stains on clothing, furniture and wallpaper can react with a common indoor pollutant to generate dangerous chemicals TSNAs.

Citing the ill-effects it posted that human exposure to TSNAs is most likely to result via either inhalation of dust or the contact of skin with carpet or clothes, rendering third-hand smoke particularly dangerous to infants and toddlers.

Researcher Lara Gundel, of the Lawrence Berkeley National Laboratory, quoted, "Smoking outside is better than smoking indoors but nicotine residues will stick to a smoker's skin and clothing”.