Abstract
A recently introduced technique based on differential optical absorption spectroscopy (DOAS) was compared with conventional adsorption sampling and gas chromatography for the determination of aromatic hydrocarbons in air. Measurements were made in Switzerland and Sweden, at sites with benzene and toluene concentrations up to 20 and 40 μg m−3, respectively. The hydrocarbons determined originated mainly from traffic exhaust. The results demonstrate that the version of DOAS studied is a versatile tool for continuous monitoring of benzene and toluene in air at concentrations higher than 10 μg m−3.