What are aryl hydrocarbons?
Aryl hydrocarbons are hydrocarbons that contain benzene rings.
Chemists call them aromatic hydrocarbons or arenes.
Many aromatic compounds have a sweet or pleasant odour. That gives rise to the word aryl, a combination of the word aromatic and the substituent ending –yl.
The simplest aromatic compounds contain a single benzene ring. They are monocyclic aromatic hydrocarbons (MAHs).
Many aromatic hydrocarbons contain more than one aromatic ring. They are polycyclic aromatic hydrocarbons (PAHs).
PAHs that contain 2 or 3 benzene rings are highly toxic to aquatic organisms. Many that contain 4 or more aromatic rings are carcinogenic.
Molecular biologists often refer to aryl hydrocarbon receptors. These are proteins that bind to specific DNA sequences and are involved in the body's response to aromatic hydrocarbons.