Petroleum, uncombusted

Polycyclic aromatic hydrocarbons (PAHs) are produced during the incomplete combustion of organic material. PAHs can also be produced through natural, non-combustion processes, and they may be present in uncombusted petroleum. Uncombusted petroleum can be a direct source to the waters of... 

Kainz RJ, White EE. 1984. Depressant effects associated with the inhalation of uncombusted diesel vapor. In MacFarland HN, Holdsworth CE, MacGregor JA, et al., eds. Advances in modem environmental toxicology. Volume VI Applied toxicology of petroleum hydrocarbons. Princeton, NJ Princeton Scientific Publishers, Inc. 

Once produced PAHs can be transported through the atmosphere or the water column if directly discharged via uncombusted petroleum. In the air, PAHs partition between the gas and particle phases, can undergo photochemical and oxidation reactions, be washed out by precipitation and deposit to aquatic surfaces by both wet and dry deposition. Once in the aquatic system, PAHs partition between the dissolved and particulate phases, can undergo photochemical reactions and bioaccumulate in the lower trophic levels. 

PAHs to distinguish them from the petrogenic PAHs derived directly from uncombusted petroleum, coal, and their by-products. Natural sources such as forest fires could be important in less inhabited and remote watersheds, but anthropogenic combustion of fossil fuel (e.g., petroleum, coal) and wood is the dominant source of pyrogenic PAHs (Neff, 1979 Bjorseth and Ramdahl, 1983 Ballentine et al., 1996 O Malley et ai, 1997). 

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