In general, aromatics composed of o

In general, aromatics composed of one, two, or three condensed rings are transformed rapidly and often completely mineralized, whereas aromatics containing four or
more condensed rings are transformed much more slowly, often as a result of cometabolic attack. This is due to the limited bioavailability of these high-molecular-weight aromatics. Such PAH have very limited aqueous solubility and sorb strongly to particle surfaces in soil and sediments. However, it has been demonstrate d that chronic exposure
to aromatic compounds will result in increased transformation rates because of adaptation of an indigenous population to growth on aromatic compounds.