Dibenz 'a'',''j''nthracene or Benzo etraphene or 1,2:7,8-Dibenzanthracene is an organic compound with the chemical formula C₂₂H₁₄. It belongs to the class of polycyclic aromatic hydrocarbons (PAHs) and is formed whenever there is

incomplete combustion Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combusti ...

of organic matter. The IARC (International Agency for Research on Cancer) has classified it as ''possibly carcinogenic'' to humans, grouped into IARC group 2B.

Description

Dibenz(a,j)anthracene is a polycyclic aromatic hydrocarbon with five benzene rings. It has low water solubility and low volatility and therefore occurs predominantly in solid form, bound to particulates in polluted air, soil, or sediment.

Occurrence

Dibenz(a,j)anthracene is generated whenever organic matter or fuel is incompletely burnt or combusted. Examples include industrial emissions such as coke oven operations in the coal and steel industry, coal tar distillation, or within

engine exhaust Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline (petrol), diesel fuel, fuel oil, biodiesel blends, or coal. According to the type of engine, it is discharged into the atmosphere through an ...

. On a personal level it is produced with high temperature cooking like

frying Frying is the cooking of food in oil or another fat. Similar to sautéing, pan-fried foods are generally turned over once or twice during cooking to make sure that the food is well-made, using tongs or a spatula, while sautéed foods are cooked ...

grilling Grilling is a form of cooking that involves dry heat applied to the surface of food, commonly from above, below or from the side. Grilling usually involves a significant amount of direct, radiant heat, and tends to be used for cooking meat a ...

, broiling,

roasting Roasting is a cooking method that uses dry heat where hot air covers the food, cooking it evenly on all sides with temperatures of at least from an open flame, oven, or other heat source. Roasting can enhance the flavor through caramelization ...

and baking, but also when cigarette smoking or

marijuana smoking Cannabis smoking (or Colloquialism, colloquially smoking pot) is the inhalation of smoke or vapor released by heating the flowers, leaves, or extracts of Cannabis (drug), cannabis and releasing the main Psychoactive drug, psychoactive chemical ...

Health effects

As of 2010, the IARC (International Agency for Research on Cancer) has classified dibenz(a,j)anthracene as ''possibly carcinogenic'' to humans, grouped into IARC group 2B. No epidemiological studies on human exposure to dibenz(a,j)anthracene as an individual PAH exist, because PAHs always occur as components of complex

chemical mixture In chemistry, a mixture is a material made up of two or more different chemical substances which are not chemically bonded. A mixture is the physical combination of two or more substances in which the identities are retained and are mixed in the ...

s and never occur in isolation in the environment. PAHs all have a similar mechanism of causing cancer in both humans and experimental animals whereby they are metabolically converted to oxides and dihydrodiols, and then oxidized to

diol A diol is a chemical compound containing two hydroxyl groups ( groups). An aliphatic diol is also called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified. The most common industrial diol is e ...

epoxides, which react with DNA, inducing mutations.

In space

In February 2014, NASA announced a database for tracking polycyclic aromatic hydrocarbons (PAHs), including dibenz 'a'',''j''nthracene, in the universe. According to scientists, more than 20% of the carbon in the universe may be associated with PAHs, possible starting materials for the

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondar ...

of life. PAHs seem to have been formed shortly after the

Big Bang The Big Bang event is a physical theory that describes how the universe expanded from an initial state of high density and temperature. Various cosmological models of the Big Bang explain the evolution of the observable universe from the ...

, are widespread throughout the universe, and are associated with new stars and exoplanets.

References

Polycyclic aromatic hydrocarbons IARC Group 3 carcinogens {{hydrocarbon-stub

Description

Occurrence

Health effects

In space

See also

References