A method was developed for the determinations of seven BTEX(the term used for a group of volatile aromatic compounds),including benzene,toluene,ethylbenzene,p-xylene,m-xylene,o-xylene and styrene,in seawater by purge and trap gas chromatography-mass spectrometry under selective ion monitoring (SIM) mode.The result showed that the calibration curves of seven BTEX were in the range of 100.0-2 000.0 ng/L,with correlation coefficients of 0.999 6-0.999 8.The method detection limits ranged from 5.9 ng/L to 10.7 ng/L.The average recoveries for seven BTEX at two spiked concentration levels of 250.0 ng/L and 1 000.0 ng/L were in the range of 84%-105% and 96%-97%,with relative standard deviations(RSDs,n=6) of 3.7%-6.5% and 2.1%-3.3%,respectively.This method is accurate and rapid,and has high enrichment efficiency without any organic contamination,which can be used to analyze seawater samples containing trace BTEX. |