low concentrations of pah are also found in connection with forest fires. furthermore, analysis of soils with high content of organic material often indicates a natural background of hydrocarbons, and these can be confused with pah unless a gc-ms analysis is carried out to confirm identification of the hydrocarbons.

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Low concentrations of PAH are also found in connection with forest fires. Furthermore, analysis of soils with high content of organic material often indicates a natural background of hydrocarbons, and these can be confused with PAH unless a GC-MS analysis is carried out to confirm identification of the hydrocarbons.