Polyaromatic hydrocarbons (PAH?s) are large organic compounds produced during combustion. Many of these compounds are carcinogenic and are often found in water, air and other natural habitats. Monitoring of these compounds is very crucial for a healthy environment. The major challenge in HPLC analysis of PAH?s is in the resolution of their structurally similar isomers. The figure shows the resolution of 16 PAH?s designated as Priority pollutants by the US EPA. SMT PAH1 columns consist of octadecyl functional ligands and are made with silica with proprietary pore size.