Tar is the name for the

resin In polymer chemistry and materials science, resin is a solid or highly viscous substance of plant or synthetic origin that is typically convertible into polymers. Resins are usually mixtures of organic compounds. This article focuses on nat ...

ous, combusted

particulate matter Particulates – also known as atmospheric aerosol particles, atmospheric particulate matter, particulate matter (PM) or suspended particulate matter (SPM) – are microscopic particles of solid or liquid matter suspended in the air. The te ...

made by the burning of

tobacco Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...

and other plant material in the act of

smoking Smoking is a practice in which a substance is burned and the resulting smoke is typically breathed in to be tasted and absorbed into the bloodstream. Most commonly, the substance used is the dried leaves of the tobacco plant, which have b ...

. Tar is toxic and damages the smoker's

lungs The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either si ...

over time through various biochemical and mechanical processes. Tar also damages the mouth by rotting and blackening teeth, damaging gums, and desensitizing taste buds. Tar includes the majority of

mutagen In genetics, a mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer i ...

ic and

carcinogen A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive sub ...

ic agents in tobacco smoke.

Polycyclic aromatic hydrocarbon A polycyclic aromatic hydrocarbon (PAH) is a class of organic compounds that is composed of multiple aromatic rings. The simplest representative is naphthalene, having two aromatic rings and the three-ring compounds anthracene and phenanthrene. ...

s (PAH), for example, are

genotoxic Genotoxicity is the property of chemical agents that damage the genetic information within a cell causing mutations, which may lead to cancer. While genotoxicity is often confused with mutagenicity, all mutagens are genotoxic, but some genotoxic s ...

and epoxidative. Cigarette companies in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

, when prompted to give tar/

nicotine Nicotine is a naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and '' Duboisia hopwoodii'') and is widely used recreationally as a stimulant and anxiolytic. As a pharmaceutical drug, it is use ...

ratings for cigarettes, usually use "tar", in quotation marks, to indicate that it is not the road surface component. Tar is occasionally referred to as an acronym for ''total aerosol residue'', a

backronym A backronym is an acronym formed from an already existing word by expanding its letters into the words of a phrase. Backronyms may be invented with either serious or humorous intent, or they may be a type of false etymology or folk etymology. The ...

coined in the mid-1960s. Tar, when in the lungs, coats the cilia causing them to stop working and eventually die, causing conditions such as

lung cancer Lung cancer, also known as lung carcinoma (since about 98–99% of all lung cancers are carcinomas), is a malignant lung tumor characterized by uncontrolled cell growth in tissues of the lung. Lung carcinomas derive from transformed, mali ...

as the toxic particles in tobacco smoke are no longer trapped by the cilia but enter the

alveoli Alveolus (; pl. alveoli, adj. alveolar) is a general anatomical term for a concave cavity or pit. Uses in anatomy and zoology * Pulmonary alveolus, an air sac in the lungs ** Alveolar cell or pneumocyte ** Alveolar duct ** Alveolar macrophage * M ...

directly. Thus, the alveoli cannot come through with the process that is called ‘gas exchange’ which is the cause of rough breathing. Cannabis when burned also creates biological residue that is very similar to the "tar" created by tobacco smoke.

Long-term effects

Lung cancer

One of the most well known diseases caused by smoking is

. A few

carcinogens A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive sub ...

commonly found in

tar Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. "a dark brown or black bi ...

include

benzene Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms ...

acrylamide Acrylamide (or acrylic amide) is an organic compound with the chemical formula CH2=CHC(O)NH2. It is a white odorless solid, soluble in water and several organic solvents. From the chemistry perspective, acrylamide is a vinyl-substituted primar ...

and

acrylonitrile Acrylonitrile is an organic compound with the formula and the structure . It is a colorless, volatile liquid although commercial samples can be yellow due to impurities. It has a pungent odor of garlic or onions. In terms of its molecula ...

. Smoking exposes delicate cells inside the lungs directly to these compounds. This causes mutations in the DNA of the cells, which leads to cancer. According to the World Health Organization's report, "Tobacco Smoke and Involuntary Smoking", 80 percent of all cases of lung cancer are attributable to smoking.

Third-hand smoking and its effects

Third-hand smoke is residual nicotine and other chemicals left on a variety of indoor surfaces by tobacco smoke. This residue reacts with indoor pollutants to create a toxic mix. Containing cancer-causing substances, this third-hand smoke poses a potential health hazard to nonsmokers who are exposed to it, especially children. Studies have shown that third-hand smoke clings to many things such as hair, skin, clothes, furniture, drapes, walls, bedding, carpets, dust, vehicles and other surfaces, even long after smoking has stopped. Individuals at risk such as infants, children and nonsmoking adults may suffer tobacco-related health problems when they inhale, ingest or touch substances containing third-hand smoke. Third-hand smoke is a relatively new concept, and researchers are still studying its possible dangers. Third-hand smoking can be a serious concern, as it affects other people's health. In a house, the tobacco residue of the smoke can build up on surfaces over time. Unfortunately, excess smoke can not be removed just by airing out rooms and opening windows. Scientists have reported that third-hand smoke may cause up to 60 percent of the harm caused by regular exposure to smoke.

Second-hand smoking vs third-hand smoking

Second-hand smoking (SHS) is a combination of

sidestream smoke Sidestream smoke is smoke which goes into the air directly from a burning cigarette, cigar, or smoking pipe. Sidestream smoke is the main component (around 85%) of second-hand smoke (SHS), also known as Environmental Tobacco Smoke (ETS) or passiv ...

(i.e., smoke emitted from the burning cigarette, pipe, or cigar) and the mainstream smoke exhaled from the lungs of smokers. It contains more than 4,000 chemicals, many of which are known to affect health. These may include ammonia, acrolein, carbon monoxide, hydrogen cyanide, nicotine, nitrogen oxides, arsenic, and sulfur dioxide, many of which contain irritants and toxicants to the eye and respiratory tract. Third-hand smoking (THS) consists of residual tobacco smoke pollutants that remain on surfaces and in dust after tobacco has been smoked, are re-emitted into the gas phase, or react with oxidants and other compounds in the environment to yield secondary pollutants. Chemicals of tobacco smoking include nicotine, 3-ethenylpyridine (3-EP), phenol, cresols, naphthalene, formaldehyde, and tobacco-specific nitrosamines (including some not found in freshly-emitted tobacco smoke).

References

{{DEFAULTSORT:Tar (Tobacco Residue) Tobacco