Objective To establish a method for the determination of 8 volatile halogenated hydrocarbons in drinking water， including vinyl chloride， trichloroethylene， tetrachloroethylene， tetrachloromethane， chloroform， dichlorobromomethane， dichlorodibromomethane， and tribromomethane by headspace thermal desorption-gas mass spectrometry.

Methods The water sample was kept in the headspace bottle at 60 ℃ for 40 min， and the volatile matter was transferred to the cold trap，subjected to thermal desorption， then analyzed by gas chromatography-mass spectrometry.

Results The linear ranges were 0.2‒20.0 μg·L^-1 for vinyl chloride， 0.1‒20.0 μg·L^-1 for chloroform， 0.02‒20.00 μg·L^-1 for tetrachloromethane， 0.2‒20.0 μg·L^-1 for trichloroethylene， 0.3‒20.0 μg·L^-1 for dichlorobromomethane， 0.1‒20.0 μg·L^-1 for tetrachloroethylene， 0.4‒20.0 μg·L^-1 for dichlorodibromomethane， and 1.0‒20.0 μg·L^-1 for tribromomethane. All the correlation coefficients were more than 0.997. The respective quantitative limits were 0.162， 0.073， 0.016， 0.184， 0.270， 0.071， 0.356 and 0.813 μg·L^-1， and the respective recoveries were 98.0%‒101.0%， 102.0%‒110.0%， 99.2%‒101.0%， 95.5%‒96.2%， 96.0%‒102.0%， 100.0%‒102.0%， 99.0%‒105.0%， and 94.0%‒103.0%.

Conclusion The method is simple， sensitive， rapid， accurate and reliable， so it is applicable for the determination of 8 kinds of volatile halogenated hydrocarbons in drinking water.