摘要：The paper presents the application of a method based on coupled gas chromatography-mass spectrometry, using an isotopically labelled internal standard for the quantitative analysis of benzene (B), toluene (T), ethyl benzene (E), and o-, m-, p-xylenes (X). Their atmospheric concentrations were determined based on short-term sampling, in different sites of Cluj-Napoca, a highly populated urban centre in N-W Romania, with numerous and diversified road vehicles with internal combustion engines. The method is relatively inexpensive and simple and shows good precision and linearity in the ranges of 7–60 𝜇g/m3
(B), 13–90 𝜇g/m3
(T), 7–50 𝜇g/m3
(E), 10–70 𝜇g/m3
(X-m,p), and 20–130 𝜇g/m3
(X-o). The limits of quantitation/detection of the method LOQ/LOD are of 10/5 𝜇g/m3
(Xo), 5/3 𝜇g/m3
(B, E, X-m,p), and of 3/1 𝜇g/m3 (T), respectively.
