This part of ISO 7981 specifies the determination of six selected PAH in drinking, mineral and table waters and ground and surface waters in mass concentrations above 0,005 µg/l, by high-performance liquid chromatography with fluorescence detection after liquid-liquid extraction. The six PAH are: fluoranthene, benzo[b]fluoranthene, benzo[a]pyrene, benzo[k]fluoranthene, indeno[1,2,3-cd]pyrene, and benzo[ghi]perylene (see Table 1). With some modification, this method is also applicable for the analysis of moderately polluted waste waters.