Simultaneous determination of benzene and toluene in the blood using head-space gas chromatography.

A head-space method for the simultaneous determination of benzene and toluene in blood using a gas chromatograph equipped with a photoionization detector was developed. Internal standards for benzene and toluene were fluorobenzene and o-xylene, respectively, and the detection limit was 5 nmol/l for both solvents. This method is sensitive enough for needs of biological monitoring of benzene and toluene in exposed workers. With automation it offers a possibility for routine measurements. An application of the method in monitoring exposed workers in the industry is presented.