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Monocyclic aromatic hydrocarbons are used in various industrial processes, including the
production of chemicals, drugs, paints, and enamels, and they are thus widespread environmental
contaminants. Several bacterial strains are known that have the ability to grow on different alkilbenzenes,
including the three xylene isomers, as the sole source of carbon and energy. Bacteria
that degrade xylenes commonly fall into two classes: those that can degrade both m- and
p-xylene, and those that can degrade o-xylene only. Very rarely are the two abilities found
together in the same organism. The positions of the methyl groups on the aromatic ring thus play
a major role in the selection of bacteria able to grow on the xylene isomers.
Biotransformation of several aromatic hydrocarbons including benzene, toluene,
ethylbenzene, m-xylene, p-xylene, and o-xylene (BTEX) was studied by several authors. However
other substituted alkilbenzenes present in different elements of the environment at much higher
concentrations were not discussed.
In present study levels and possible transformation pathways BTEX and other monoaromatic
compounds in different stages of wastewater treatment plant (WWTP) are discussed.
In our investigations, SPME was used at isolation and preconcentration step and for the
final determinations GC-MS system (Trace-Ultra/PolarisQ) was used. At the first step (isolation and
preconcentration) fibers characterized with different polarity were applied for determination of
compounds with different polarity, which can be possible transformation products of
monoaromatic compounds.
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