Solid phase extraction is often used in laboratories
due to its rapidity [7]. Therefore, the required material
for the SPE procedure is very simple, and can be
used in combination with field adapted equipment for
the determination of PAH concentrations in contaminated
soils. In this case, the SPE methods use hexane
as the percolation solution for the sample on a polar
phase (only silica gel or combination of cyanopropyl
bounded silica and silica gel). However, for many
authors, hexane leads to poor extraction recovery of
PAHs.