Any of a class of hydrocarbon molecules with multiple carbon rings that include numerous carcinogenic substances and environmental pollutants.

one of a class of hydrocarbon compounds containing more than one aromatic ring structure; e.g., naphthalene

Any of various organic compounds composed of a few to many six-membered rings of carbon atoms linked by an alternating sequence of single and double bonds and to which hydrogen atoms are attached.

a chemical compound composed of fused six carbon rings.

A group of aromatic hydrocarbons having three or more aromatic nuclei in their structures.

A class of organic compounds with a fused-ring aromatic structure. PAHs result from incomplete combustion of organic carbon (including wood), municipal solid waste, fossil fuels, and natural or anthropogenic introduction of uncombusted coal and oil. PAHs include benzo(a)pyrene, fluoranthene, and pyrene.

Polycyclic aromatic hydrocarbons (PAHs) are chemical compounds that consist of fused aromatic rings and do not contain heteroatoms or carry substituents. These compounds can be point source pollutants (e.g. oil spill) or non-point source (e.g. atmospheric deposition) and are one of the most widespread organic pollutants. Some of them are known or suspected carcinogens, and are linked to other health problems.