Couldn't find what you looking for?


Table of Contents

New evidence suggests that residues from second-hand smoke can interact with other indoor air pollutants to form toxic chemicals, which can be inhaled or ingested. This consists of third-hand smoke, which is a potential source of toxicity and disease.

Most of us already know about the dangers of smoking and inhaling secondhand smoke. But now, new findings reveal that we are not safe from carcinogens coming from tobacco, just because we do not inhale visible smoke directly. Scientists have found that residual nicotine, as well as other chemicals, left on various surfaces long after cigarette smoke has been cleared from the air, consists of third-hand smoke. This mixture of toxic chemicals continues to float in the air, cling to clothes, hair, carpets, furniture and most surfaces, and pose a threat to health even when the smoker has left the room.

What Is Third-Hand Smoke?

Third-hand smoke (THS) is secondhand smoke that accumulates on surfaces and ages with time, then progressively becomes more toxic.

It is a potential health hazard to children, spouses, workers, and other people who are exposed to the residues where tobacco smoking has occurred or is being allowed. This includes public places like restaurants and hotels, vehicles, abandoned apartments, children's bedrooms, and other places which were once used or is still being used by smokers. One also inhales THS when a smoker enters an elevator and people around him smell nicotine fuming from his hair and clothes. The worst thing is that even if a contaminated room is cleaned, vacuumed, aired out, or repainted, chemical residues still remain on surfaces and everyone who is exposed to these substances are still at risk for health problems.

THS represents a third way people can be exposed to nicotine and other chemicals contained in cigarettes. One study, published in the Environmental Science & Technology journal, showed that cigarettes residues can interact with dust, ozone and other indoor air pollutants and form airborne particles to be inhaled again. The researchers also found that low humidity increases one's risk for exposure to these particles while high levels of humidity may be protective against it.

There are about 250 harmful chemicals found in cigarette smoke, including lead, toluene, carbon monoxide, arsenic and cyanide.

Researchers from MassGeneral Hospital for Children in Boston who first coined the term “third-hand smoke” in a 2009 study interviewed about 1,500 US households and found that most smokers and non-smokers were aware of the dangers of secondhand smoke but not THS. The survey showed that although most people are aware that smoking and inhaling secondhand smoke can harm one's health, not many people know that they may still be exposed to the dangers of THS long after the smoke is seen from the air. Furthermore, few people know that these environmental toxins are not only inhaled, they may also enter the skin or be ingested through contaminated hands.

The dangers of smoking and secondhand smoke have been documented in many studies, linking these two types of nicotine exposure to several diseases including various types of cancer, cardiovascular disease, stroke, and other conditions. However, although initial studies suggest that chemicals that persist in indoor air from secondhand smoke may be harmful, solid evidence linking THS to specific diseases are still lacking. It is nevertheless worthwhile to consider some points about existing data, which may help us look deeper into whether or not we should worry about THS.

Continue reading after recommendations

  • Martins-Green M, Adhami N, Frankos M, et al. Cigarette Smoke Toxins Deposited on Surfaces: Implications for Human Health. PLOS One.
  • DOE/Lawrence Berkeley National Laboratory. Carcinogens form from third-hand smoke. ScienceDaily. ScienceDaily, 9 February 2010.
  • WebMD. Risks of Thirdhand Cigarette Smoke Can Linger.
  • Hang B, Sarker A, Havel C, et al. Thirdhand smoke causes DNA damage in human cells. Mutagenesis, 2013.
  • Huffington Post. Your Nose Knows: The Invisible Threat of 'Thirdhand Smoke.'
  • Photo by
  • Photo courtesy of Kristaps Bergfelds by Flickr :

Your thoughts on this

User avatar Guest