As a sequel to an earlier paper, we have studied the behaviour of 1-fluoropyrene and pyrene in lamp-excited Shpol'skii spectrofluorimetry at 11K in two different matrices, n-octane and n-hexane, using two different solidification processes. Particular attention is paid to the suitability of 1-fluoropyrene as an internal standard (IS) to correct for different sources of variability. As a demonstration of the applicability of this approach, four polycyclic aromatic hydrocarbons (PAHs; pyrene, chrysene, benzo[a]pyrene and benzo[k]fluoranthene) were determined in a river sediment extract. The results agreed well with those obtained by HPLC with fluorescence detection. © 2002 Elsevier Science B.V. All rights reserved.