PURGE-AND-TRAP INJECTION CAPILLARY GAS-CHROMATOGRAPHIC DETERMINATION OF VOLATILE AROMATIC-HYDROCARBONS IN RIVER SEDIMENT

Dynamic headspace and purge-and-trap with methanolic extraction techniques for the simple and rapid determination of trace amounts of volatile aromatic hydrocarbons in river sediments were compared. The purge-and-trap technique with metanolic extraction using an external standard method gives a better representativeness of the analysed sample, a twofold higher precision and twofold lower detection limits. When the internal standard method is applied, the precision of both methods increases 3-4 times and the detection limits decrease 4-5 times.