| A method of headspace gas chromatography-mass spectrometry(HS/GC-MS) was developed for the determination of eight volatile benzene homologues,i.e.benzene,toluene,ethylbenzene,p-xylene,m-xylene,isopropylbenzene,o-xylene and styrene in ball-point pen.The equilibrium temperature and time for headspace sampler were set at 70 ℃ and 40 min,respectively.The analytes were separated on an HP-INNOWax column(60 m×320 μm×0.25 μm),then detected in selected-ion monitoring mode and quantified by external standard method.Results showed that the standard curves for eight benzene homologues were linear over the concentration range of 0.005-0.05 mg/L with the linear correlation coefficients greater than 0.999.The detection limits of the method(S/N=3) were in the range of 0.01-0.02 mg/kg.The spiked recoveries ranged from 86.0% to 104% with RSDs of 2.3%-9.6%.The method is simple,rapid and high sensitive,and is suitable for the determination of volatile benzene homologues in ball-point pen. |