What are examples of PAHs?

The following are examples of PAHs that vary in the number and arrangement of their rings:

• Examples of polycyclic aromatic hydrocarbons.
• Naphthalene.
• Biphenyl.
• Fluorene.
• Anthracene.
• Phenanthrene.
• Phenalene.
• Tetracene.

What are polycyclic aromatic hydrocarbons PAHs )? Astronomy?

Polycyclic aromatic hydrocarbons (PAHs) have a poor name. They constitute a group of hundreds of organic materials made up of two or more benzene rings.

What are PAHs and why are they important?

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants generated primarily during the incomplete combustion of organic materials (e.g. coal, oil, petrol, and wood). Atmospheric deposition is a major source for PAHs in soil. Many PAHs have toxic, mutagenic and/or carcinogenic properties.

Is PAH toxic?

PAHs generally have a low degree of acute toxicity to humans. The most significant endpoint of PAH toxicity is cancer. Increased incidences of lung, skin, and bladder cancers are associated with occupational exposure to PAHs.

What are the main sources of aromatic hydrocarbons?

Simple aromatic hydrocarbons come from two main sources: Coal and petroleum. Coal is a complex mixture of a large number of compounds, most of which are long-chain compounds. If coal is heated to about 1000 °C in the absence of air (oxygen), volatile components, the so-called tar oil, are stripped out.

How are aromatic hydrocarbons made?

Aromatic hydrocarbons are a special class of unsaturated hydrocarbon based on a six carbon ring moiety called benzene. The saturated hydrocarbon cyclohexane is transformed into the aromatic hydrocarbon benzene by adding three alternating carbon–carbon double bonds, as shown in Fig.

What elements are found in PAHs?

PAHs consist of two or more fused aromatic rings. They predominantly consist of carbon or hydrogen but may also contain oxygen, nitrogen and sulfur. When PAHs contain these other elements, they are called heterocyclic PAHs, but these a rarely measured or reported in most routine PAH studies.

How polycyclic aromatic hydrocarbons are formed?

PAHs are formed as a result of incomplete combustion of carbon-containing materials, such as wood, coal, oil, gas, or biomass. They are also created in car and diesel exhaust, smoked or charbroiled food, and are present in cigarette smoke condensate, and tobacco products.

What do PAHs cause?

It is not clear that PAHs cause short-term health effects. Other compounds commonly found with PAHs may be the cause of short-term symptoms such as eye irritation, nausea, vomiting, diarrhea, and confusion. Long-term health effects of exposure to PAHs may include cataracts, kidney and liver damage, and jaundice.

Where is PAH found?

Polycyclic aromatic hydrocarbons (PAHs) are a class of chemicals that occur naturally in coal, crude oil, and gasoline. They also are produced when coal, oil, gas, wood, garbage, and tobacco are burned. PAHs generated from these sources can bind to or form small particles in the air.

How are PAHs formed?

Where are aromatic hydrocarbons found?

Polycyclic aromatic hydrocarbons (PAHs) are a class of chemicals that occur naturally in coal, crude oil, and gasoline. They also are produced when coal, oil, gas, wood, garbage, and tobacco are burned.