AbstractA 15 m DB‐17 fused‐silica capillary column has been used to achieve the separation of all mononitrofluorarthene and mononitropyrene isomers. Linear Retention Indices and Relative Retention times for each component have been measured and the values were compared with those observed on DB‐5 columns, commonly used for this separation. Increased polarity of the liquid phase results in better separation of some key isomeric pairs (such as 2‐, 3‐nitrofluoranthene and 1‐nitropyrene, 8‐nitrofluoranthene), difficult to resolve on DB‐5 columns. Practical applications are reported. They include the analysis of extracts from emission samples (diesel exhaust and particles emitted by a factory manufacturing carbon electrodes) as well as atmospheric dust sampled in a urban area under diffe